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  Subjects -> FORESTS AND FORESTRY (Total: 104 journals)
Acta Silvatica et Lignaria Hungarica     Open Access   (Followers: 1)
Advance in Forestry Research     Open Access   (Followers: 5)
Advances in Forestry Letters     Open Access   (Followers: 1)
Advances in Forestry Science     Open Access  
African Journal of Sustainable Development     Full-text available via subscription   (Followers: 6)
Agrociencia     Open Access   (Followers: 2)
Agroforestry Systems     Hybrid Journal   (Followers: 17)
Annals of Forest Science     Hybrid Journal   (Followers: 5)
Annals of Silvicultural Research     Open Access   (Followers: 1)
Appita Journal: Journal of the Technical Association of the Australian and New Zealand Pulp and Paper Industry     Full-text available via subscription   (Followers: 6)
Arboricultural Journal : The International Journal of Urban Forestry     Hybrid Journal   (Followers: 7)
Arboriculture and Urban Forestry     Free   (Followers: 8)
Australian Forest Grower     Full-text available via subscription   (Followers: 2)
Australian Forestry     Full-text available via subscription   (Followers: 3)
Banko Janakari     Open Access  
Boletin de la Sociedad Argentina de Botanica     Open Access   (Followers: 1)
Bosque     Open Access   (Followers: 1)
Canadian Journal of Forest Research     Full-text available via subscription   (Followers: 26)
Canadian Journal of Plant Science     Full-text available via subscription   (Followers: 15)
Ciência Florestal     Open Access   (Followers: 3)
Ciencia forestal en México     Open Access   (Followers: 1)
Colombia Forestal     Open Access  
Current Forestry Reports     Hybrid Journal  
Dissertationes Forestales     Open Access  
European Journal of Forest Research     Hybrid Journal   (Followers: 6)
Expert Opinion on Environmental Biology     Hybrid Journal  
Floresta e Ambiente     Open Access   (Followers: 1)
Folia Forestalia Polonica     Open Access   (Followers: 1)
Forest Ecology and Management     Hybrid Journal   (Followers: 48)
Forest Pathology     Hybrid Journal   (Followers: 2)
Forest Phytophthoras     Open Access   (Followers: 2)
Forest Policy and Economics     Hybrid Journal   (Followers: 21)
Forest Research Papers     Open Access   (Followers: 4)
Forest Science     Full-text available via subscription   (Followers: 8)
Forest Science and Practice     Hybrid Journal   (Followers: 6)
Forest Science and Technology     Partially Free   (Followers: 2)
Forest Systems     Open Access   (Followers: 3)
Foresta Veracruzana     Open Access   (Followers: 2)
Forestry Chronicle     Full-text available via subscription   (Followers: 12)
Forestry Letters     Open Access  
Forestry Studies : Metsanduslikud Uurimused     Open Access   (Followers: 2)
Forestry: An International Journal of Forest Research     Hybrid Journal   (Followers: 17)
Forests     Open Access   (Followers: 4)
Forests, Trees and Livelihoods     Partially Free   (Followers: 5)
Ghana Journal of Forestry     Full-text available via subscription   (Followers: 1)
Holzforschung     Hybrid Journal  
iForest : Biogeosciences and Forestry     Open Access   (Followers: 2)
Indian Forester     Full-text available via subscription  
INNOTEC : Revista del Laboratorio Tecnológico del Uruguay     Open Access  
International Forestry Review     Full-text available via subscription   (Followers: 8)
International Journal of Agriculture and Forestry     Open Access   (Followers: 5)
International Journal of Forest Engineering     Hybrid Journal   (Followers: 1)
International Journal of Forest, Soil and Erosion     Open Access   (Followers: 5)
International Journal of Forestry Research     Open Access   (Followers: 5)
Journal of Agriculture, Forestry and the Social Sciences     Full-text available via subscription   (Followers: 3)
Journal of Biodiversity Management & Forestry     Hybrid Journal   (Followers: 1)
Journal of Environmental Extension     Full-text available via subscription  
Journal of Forest and Livelihood     Open Access  
Journal of Forest Economics     Hybrid Journal   (Followers: 6)
Journal of Forest Products and Industries     Open Access  
Journal of Forest Research     Hybrid Journal   (Followers: 4)
Journal of Forestry     Full-text available via subscription   (Followers: 15)
Journal of Forestry Research     Hybrid Journal   (Followers: 7)
Journal of Horticulture and Forestry     Open Access   (Followers: 1)
Journal of Natural Resources Policy Research     Hybrid Journal   (Followers: 15)
Journal of Research in Forestry, Wildlife and Environment     Open Access   (Followers: 3)
Journal of Sustainable Forestry     Hybrid Journal   (Followers: 8)
Journal of the Faculty of Forestry Istanbul University     Open Access  
Journal of Tropical Forestry and Environment     Open Access   (Followers: 1)
Journal of Wood Chemistry and Technology     Hybrid Journal   (Followers: 7)
Journal of Wood Science     Hybrid Journal   (Followers: 4)
Jurnal Manajemen Hutan Tropika     Open Access   (Followers: 2)
Jurnal Penelitian Kehutanan Wallacea     Open Access  
La Calera     Open Access  
Landscapes     Hybrid Journal   (Followers: 18)
Lesnícky časopis     Open Access  
Maderas. Ciencia y tecnología     Open Access  
Mathematical and Computational Forestry & Natural-Resource Sciences     Free  
Natural Areas Journal     Full-text available via subscription   (Followers: 9)
New Forests     Hybrid Journal   (Followers: 2)
New Zealand Journal of Forestry Science     Open Access   (Followers: 1)
Open Journal of Forestry     Open Access   (Followers: 3)
Pesquisa Florestal Brasileira     Open Access   (Followers: 1)
Plant Science Bulletin     Free   (Followers: 8)
Quebracho. Revista de Ciencias Forestales     Open Access   (Followers: 1)
Research Journal of Forestry     Open Access   (Followers: 4)
Revista Árvore     Open Access   (Followers: 2)
Revista Chapingo. Serie Ciencias Forestales y del Ambiente     Open Access   (Followers: 2)
Revista de Agricultura Neotropical     Open Access  
Revista Verde de Agroecologia e Desenvolvimento Sustentável     Open Access   (Followers: 3)
Revue forestière française     Full-text available via subscription   (Followers: 3)
Rwanda Journal     Full-text available via subscription  
Scandinavian Journal of Forest Research     Hybrid Journal   (Followers: 4)
Science, Technology and Arts Research Journal     Open Access   (Followers: 1)
Silva Lusitana     Open Access  
Small-scale Forestry     Hybrid Journal   (Followers: 4)
Southern African Forestry Journal     Full-text available via subscription   (Followers: 2)
Southern Forests : a Journal of Forest Science     Hybrid Journal   (Followers: 6)
Tanzania Journal of Forestry and Nature Conservation     Full-text available via subscription   (Followers: 2)
Trees     Hybrid Journal   (Followers: 5)

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Journal Cover Forests
  [SJR: 0.629]   [H-I: 8]   [4 followers]  Follow
    
  This is an Open Access Journal Open Access journal
   ISSN (Print) 1999-4907
   Published by MDPI Homepage  [140 journals]
  • Forests, Vol. 7, Pages 27: Effects of Forest Gaps on Litter Lignin and
           Cellulose Dynamics Vary Seasonally in an Alpine Forest

    • Authors: Han Li, Fuzhong Wu, Wanqin Yang, Liya Xu, Xiangyin Ni, Jie He, Bo Tan, Yi Hu
      First page: 27
      Abstract: To understand how forest gaps and the associated canopy control litter lignin and cellulose dynamics by redistributing the winter snow coverage and hydrothermal conditions in the growing season, a field litterbag trial was conducted in the alpine Minjiang fir (Abies faxoniana Rehder and E.H. Wilson) forest in a transitional area located in the upper reaches of the Yangtze River and the eastern Tibetan Plateau. Over the first year of litter decomposition, the litter exhibited absolute cellulose loss and absolute lignin accumulation except for the red birch litter. The changes in litter cellulose and lignin were significantly affected by the interactions among gap position, period and species. Litter cellulose exhibited a greater loss in the winter with the highest daily loss rate observed during the snow cover period. Both cellulose and lignin exhibited greater changes under the deep snow cover at the gap center in the winter, but the opposite pattern occurred under the closed canopy in the growing season. The results suggest that decreased snowpack seasonality due to winter warming may limit litter cellulose and lignin degradation in alpine forest ecosystems, which could further inhibit litter decomposition. As a result, the ongoing winter warming and gap vanishing would slow soil carbon sequestration from foliar litter in cold biomes.
      PubDate: 2016-01-27
      DOI: 10.3390/f7020027
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 28: Adaptation to Climate Change in Swedish
           Forestry

    • First page: 28
      Abstract: Adaptation to climate change in forestry has become a growing concern, in part due to the impact of storms and other events that have raised the awareness of such risks amongst forest owners. Sweden is one of Europe’s most densely-forested countries, with this sector playing a major role economically. However adaptation has, to a large extent, been limited to the provision of recommendations to forest managers, most of which have only been partially implemented. This paper summarizes research with direct implications for adaptation to climate change within the forestry sector in Sweden. The focus is based in particular on providing examples of adaptations that illustrate the specific Swedish orientation to adaptation, in line with its relatively intensive forest management system. The paper thus illustrates a specific Swedish orientation to adaptation through active management, which can be contrasted with approaches to adaptation in other forestry systems, in particular those with limited management or management based on maintaining natural forests in particular.
      PubDate: 2016-01-28
      DOI: 10.3390/f7020028
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 29: Impacts of Forest to Urban Land Conversion and
           ENSO Phase on Water Quality of a Public Water Supply Reservoir

    • Authors: Emile Elias, Hugo Rodriguez, Puneet Srivastava, Mark Dougherty, Darren James, Ryann Smith
      First page: 29
      Abstract: We used coupled watershed and reservoir models to evaluate the impacts of deforestation and l Niño Southern Oscillation (ENSO) phase on drinking water quality. Source water total organic carbon (TOC) is especially important due to the potential for production of carcinogenic disinfection byproducts (DBPs). The Environmental Fluid Dynamics Code (EFDC) reservoir model is used to evaluate the difference between daily pre- and post- urbanization nutrients and TOC concentration. Post-disturbance (future) reservoir total nitrogen (TN), total phosphorus (TP), TOC and chlorophyll-a concentrations were found to be higher than pre-urbanization (base) concentrations (p < 0.05). Predicted future median TOC concentration was 1.1 mg·L−1 (41% higher than base TOC concentration) at the source water intake. Simulations show that prior to urbanization, additional water treatment was necessary on 47% of the days between May and October. However, following simulated urbanization, additional drinking water treatment might be continuously necessary between May and October. One of six ENSO indices is weakly negatively correlated with the measured reservoir TOC indicating there may be higher TOC concentrations in times of lower streamflow (La Niña). There is a positive significant correlation between simulated TN and TP concentrations with ENSO suggesting higher concentrations during El Niño.
      PubDate: 2016-01-27
      DOI: 10.3390/f7020029
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 30: Attribution Analyses of Impacts of
           Environmental Changes on Streamflow and Sediment Load in a Mountainous
           Basin, Vietnam

    • Authors: Jie Wang, Ishidaira Hiroshi, Shaowei Ning, Timur Khujanazarov, Guiping Yin, Lijuan Guo
      First page: 30
      Abstract: Located in the southeastern China and northern Vietnam, the Red River is an important international trans-boundary river that has experienced rapid deforestation and environmental changes over the past decades. We conducted attribution analysis of impacts of various environmental changes on streamflow and sediment load. The contribution of reclassified environmental changes to total change of the streamflow and sediment load was separated. Land cover change based on climate-induced and human-induced indicators were defined. We found that human-induced land cover change was the main factor affecting changes of the streamflow and sediment load. Changes of the land cover were more pronounced in the dry season than in the wet season whereas sediment load changed more in the wet season than in the dry season. In addition, changes in sediment load were mainly caused by human-induced land cover change and the changes of land cover were more influential on sediment load than on streamflow in the Red River basin.
      PubDate: 2016-01-29
      DOI: 10.3390/f7020030
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 31: Spatial Variations of Soil Moisture under
           Caragana korshinskii Kom. from Different Precipitation Zones: Field Based
           Analysis in the Loess Plateau, China

    • Authors: Yuanxin Liu, Wenwu Zhao, Lixin Wang, Xiao Zhang, Stefani Daryanto, Xuening Fang
      First page: 31
      Abstract: Soil moisture scarcity has become the major limiting factor of vegetation restoration in the Loess Plateau of China. The aim of this study is: (i) to compare the spatial distribution of deep (up to 5 m) soil moisture content (SMC) beneath the introduced shrub Caragana korshinskii Kom. under different precipitation zones in the Loess Plateau and (ii) to investigate the impacts of environmental factors on soil moisture variability. Soil samples were taken under C. korshinskii from three precipitation zones (Semiarid-350, Semiarid-410, Semiarid-470). We found that the highest soil moisture value was in the 0–0.1 m layer with a large coefficient of variation. The soil water storage under different precipitation zones increased following the increase of precipitation (i.e., Semiarid-350 < Semiarid-410 < Semiarid-470), although the degree of SMC variation was different for different precipitation zones. The SMC in the Semiarid-350 zone initially increased with soil depth, and then decreased until it reached the depth of 2.8-m. The SMC in the Semiarid-410 zone showed a decreasing trend from the top soil to 4.2-m depth. The SMC in the Semiarid-470 zone firstly decreased with soil depth, increased, and then decreased until it reached 4.6-m depth. All SMC values then became relatively constant after reaching the 2.8-m, 4.2-m, and 4.6-m depths for Semiarid-350, Semiarid-410, and Semiarid-470, respectively. The low but similar SMC values at the stable layers across the precipitation gradient indicate widespread soil desiccation in this region. Our results suggested that water deficit occurred in all of the three precipitation zones with precipitation, latitude, field capacity, and bulk density as the main environmental variables affecting soil moisture. Considering the correlations between precipitation, SMC and vegetation, appropriate planting density and species selection should be taken into account for introduced vegetation management.
      PubDate: 2016-01-29
      DOI: 10.3390/f7020031
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 32: Developing Aboveground Biomass Equations Both
           Compatible with Tree Volume Equations and Additive Systems for
           Single-Trees in Poplar Plantations in Jiangsu Province, China

    • Authors: Chao Zhang, Dao-Li Peng, Guo-Sheng Huang, Wei-Sheng Zeng
      First page: 32
      Abstract: We developed aboveground biomass equations for poplar plantations in Jiangsu Province, China, both compatible with tree volume equations and additive systems. Biomass equations were fitted with 80 selected and previously harvested sample trees. Additivity property was assured by applying a “controlling directly under total biomass proportion function” approach. Weighted regression was used to correct heteroscedasticity. Parameters were estimated using a nonlinear error-in-variable model. The results indicated that (1), on average, stems constituted the largest proportion (71.5%) of total aboveground biomass; (2) the aboveground biomass equations, both compatible with tree volume equations and additive systems, obtained good model fitting and prediction, of which the coefficient of determination ranged from 0.903 to 0.987, and the total relative error and the mean prediction error were less than 2.0% and 10.0%, respectively; (3) adding H and CW into the additive system of biomass equations did not improve model fitting and performance as expected, especially for branches and foliage biomass; and (4) the additive systems of biomass equations presented here provided more reliable and accurate biomass predictions than the independent biomass equations fitted by ordinary least square regression. This system of additive biomass equations will prove to be applicable for estimating biomass of poplar plantations in Jiangsu Province of China.
      PubDate: 2016-01-29
      DOI: 10.3390/f7020032
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 33: An Integer Programming Model to Determine Land
           Use Trajectories for Optimizing Regionally Integrated Ecosystem Services
           Delivery

    • First page: 33
      Abstract: BIOLP is an Integer Programming model based on the Balanced Compromise Programming multi-criteria decision method. The aim of BIOLP is to determine how a set of land use types should be distributed over space and time in order to optimize the multi-dimensional land performance of a region. Trajectories were defined as the succession of specific land use types over 30 years, assuming that land use changes can only occur at fixed intervals of 10 years. A database that represents the Tabacay catchment (Ecuador) as a set of land units with associated performance values was used as the input for BIOLP, which was then executed to determine the trajectories distribution that optimizes regional performance. The sensitivity of BIOLP to uncertainty in the input data, simulated through random variations on the performance values, was also tested. BIOLP showed a relative stability on its results under these conditions of stochastic, restricted changes. Additionally, the behaviour of BIOLP under different settings of its balancing and relative importance parameters was studied. Stronger variations on the outcomes were observed in this case, which indicate the influential role that such parameters play. Finally, the inclusion of performance thresholds in BIOLP was tested through the addition of sample constraints that required some of the criteria at stake to exceed predefined values. The outcome of the optimization exercises makes clear that the phenomenon of trade off between the provisioning service of the land (income) and the regulation and maintenance services (runoff, sediment, SOC) is crucial. BIOLP succeeds in accounting for this complex multi-dimensional phenomenon when determining the optimal spatio-temporal distributions of land use types. Despite this complexity, it is confirmed that the weights attributed to the provisioning or to the regulation and maintenance services are the main determinants for having the land use distributions dominated by either agriculture or forest.
      PubDate: 2016-01-30
      DOI: 10.3390/f7020033
      Issue No: Vol. 7, No. 2 (2016)
       
  • Forests, Vol. 7, Pages 11: History and Productivity Determine the Spatial
           Distribution of Key Habitats for Biodiversity in Norwegian Forest
           Landscapes

    • First page: 11
      Abstract: Retention forestry, including the retention of woodland key habitats (WKH) at the forest stand scale, has become an essential management practice in boreal forests. Here, we investigate the spatial distribution of 9470 habitat patches, mapped according to the Complementary Habitat Inventory method (CHI habitats), as potential WKHs in 10 sample areas in Norway. We ask whether there are parts of the forest landscapes that have consistently low or high density of CHI habitats compared to the surveyed landscape as a whole, and therefore have a low or high degree of conflict with harvesting, respectively. We found that there was a general pattern of clumped distribution of CHI habitats at distances up to a few kilometres. Furthermore, results showed that most types of CHI habitats were approximately two to three times as common in the 25% steepest slopes, lowest altitudes and highest site indices. CHI habitats that are most common in old-growth forests were found at longer distances from roads, whereas habitats rich in deciduous trees were found at shorter distances from roads than expected. Both environmental factors and the history of human impact are needed to explain the spatial distribution of CHI habitats. The overrepresentation of WKHs in parts of the forest landscapes represents a good starting point to develop more efficient inventory methods.
      PubDate: 2016-01-02
      DOI: 10.3390/f7010011
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 12: Propagation of Native Tree Species to Restore
           Subtropical Evergreen Broad-Leaved Forests in SW China

    • Authors: Yang Lu, Sailesh Ranjitkar, Jian-Chu Xu, Xiao-Kun Ou, Ying-Zai Zhou, Jian-Fang Ye, Xun-Feng Wu, Horst Weyerhaeuser, Jun He
      First page: 12
      Abstract: Subtropical evergreen broad-leaved forest (EBLF) is a widespread vegetation type throughout East Asia that has suffered extensive deforestation and fragmentation. Selection and successful propagation of native tree species are important for improving ecological restoration of these forests. We carried out a series of experiments to study the propagation requirements of indigenous subtropical tree species in Southwest China. Seeds of 21 tree species collected from the natural forest were materials for the experiment. This paper examines the seed germination and seedling growth performance of these species in a nursery environment. Germination percentages ranged from 41% to 96% and were ≥50% for 19 species. The median length of germination time (MLG) ranged from 24 days for Padus wilsonii to 144 days for Ilex polyneura. Fifteen species can reach the transplant size (≥15 cm in height) within 12 months of seed collection. Nursery-grown seedlings for each species were planted in degraded site. Two years after planting, the seedling survival rate was >50% in 18 species and >80% in 12 species. Based on these results, 17 species were recommended as appropriate species for nursery production in forest restoration projects. Our study contributes additional knowledge regarding the propagation techniques for various native subtropical tree species in nurseries for forest restoration.
      PubDate: 2016-01-02
      DOI: 10.3390/f7010012
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 14: Assessments of Population Structure, Diversity,
           and Phylogeography of the Swiss Needle Cast Fungus (Phaeocryptopus
           gaeumannii) in the U.S. Pacific Northwest

    • Authors: Patrick Bennett, Jeffrey Stone
      First page: 14
      Abstract: Swiss needle cast (SNC) is a foliar disease of Douglas-fir (Pseudotsuga menziesii) caused by Phaeocryptopus gaeumannii (Rohde) Petrak. This fungus is endemic to western North America, where it has historically had little impact in native forests. However, increasing disease severity in western Oregon since the 1990s has prompted renewed interest in P. gaeumannii and SNC. For this study, we analyze multilocus microsatellite genotypes from 482 single-spore isolates from 68 trees across 14 sites in the western Coast Range of Oregon and southwestern Washington. This study assesses genotypic variation and genetic structure at several levels of population hierarchy. Despite the observation that most of the genetic variation occurred within subpopulations, our analyses detected significant differentiation at all hierarchical levels. Clustering among the 482 isolates based on genetic distance clearly supports the existence of two previously described cryptic lineages of P. gaeumannii in the western United States. The two lineages occur in varying proportions along latitudinal and longitudinal gradients in western Oregon and Washington, suggesting a relationship between climate and phylogeography. Sites near Tillamook, Oregon, where SNC is most severe, consist of sympatric subpopulations in which the two lineages comprise roughly equal proportions.
      PubDate: 2016-01-06
      DOI: 10.3390/f7010014
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 15: Labile and Non-Labile Fractions of Phosphorus
           and Its Transformations in Soil under Eucalyptus Plantations, Brazil

    • First page: 15
      Abstract: Phosphorus (P) is the main limiting nutritional factor in the cultivation of Eucalyptus in Brazil. Despite this, little is known about the P fractions and dynamics in Eucalyptus soils in tropical regions. The aims of this study were (1) to evaluate the distribution of labile and non-labile fractions of P in soil in 10 sites of Eucalyptus in the state of São Paulo, Brazil and (2) to determine the interactions among the P fractions and to identify which fractions act as sinks or sources for the available P fraction. The P fractions were separated using the Hedley sequential extraction method, and the P transformation processes were evaluated via structural equation modeling. The labile P (resin-Pi + Pi and Po in NaHCO3) varied between 6% and 16%, the moderately labile P (Pi + Po in NaOH) varied between 28% and 40%, the occluded P (Pi + Po in Sonicate + NaOH) varied between 6% and 19%, the P associated with Ca (HCl-Pi) varied between 0.4% and 3% and the residual-P varied between 35% and 47%. The hypothetical structural model of soil P cycle was composed of four P pools (latent variables): the organic pool, occluded pool, inorganic pool, and available pool. The structural model was adequate to identify functional pools of P in soil, and to identify transformation processes of P based on the source-sink relationships. The available P pool was highly dependent on inorganic and occluded pools and the organic pool acted predominantly as a sink of P on available and inorganic pools. The results reinforce the high level of recalcitrance of the organic pool and the fact that Eucalyptus plants must access pools of limited-availability P to meet their nutritional demands.
      PubDate: 2016-01-06
      DOI: 10.3390/f7010015
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 16: Influences of Land Use Change on Baseflow in
           Mountainous Watersheds

    • Authors: Xu-Dong Huang, Zhi-Hua Shi, Nu-Fang Fang, Xuan Li
      First page: 16
      Abstract: It is crucial for effective water resource management in a watershed that the relationship between land use changes and baseflow. This study quantifies the influence of land use changes on the baseflow dynamics using a hydrological model and partial least-squares (PLS) regression in the Upper Du Watershed (8961 km2), China. Our study suggests that forest can be a major factor with a negative impact on the baseflow. Additionally, farmland and urban land have second-order negative effects on the baseflow dynamics. Baseflow increases when forest is replaced by farmland because the evapotranspiration (ET), associated with baseflow recession, is weaker and shorter in duration in the farmland than in the forest. The conversion of forest to urban land increases baseflow owing to the presence of non-contributing impervious surfaces in urban areas, which prevents the urban land from intercepting the baseflow discharge. These results indicate that the baseflow dynamics are closely associated with varying land use types within a watershed. Thus, this study is intended to provide a deeper understanding of the baseflow processes and useful quantitative information on land use factors in watersheds, enabling more informed decision-making in forest and watershed management.
      PubDate: 2016-01-06
      DOI: 10.3390/f7010016
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 17: Scientometrics of Forest Health and Tree
           Diseases: An Overview

    • Authors: Marco Pautasso
      First page: 17
      Abstract: Maintaining forest health is a worldwide challenge due to emerging tree diseases, shifts in climate conditions and other global change stressors. Research on forest health is thus accumulating rapidly, but there has been little use of scientometric approaches in forest pathology and dendrology. Scientometrics is the quantitative study of trends in the scientific literature. As with all tools, scientometrics needs to be used carefully (e.g., by checking findings in multiple databases) and its results must be interpreted with caution. In this overview, we provide some examples of studies of patterns in the scientific literature related to forest health and tree pathogens. Whilst research on ash dieback has increased rapidly over the last years, papers mentioning the Waldsterben have become rare in the literature. As with human health and diseases, but in contrast to plant health and diseases, there are consistently more publications mentioning “tree health” than “tree disease,” possibly a consequence of the often holistic nature of forest pathology. Scientometric tools can help balance research attention towards understudied emerging risks to forest trees, as well as identify temporal trends in public interest in forests and their health.
      PubDate: 2016-01-08
      DOI: 10.3390/f7010017
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 18: A Comparison of Hierarchical and
           Non-Hierarchical Bayesian Approaches for Fitting Allometric Larch
           (Larix.spp.) Biomass Equations

    • Authors: Dongsheng Chen, Xingzhao Huang, Xiaomei Sun, Wu Ma, Shougong Zhang
      First page: 18
      Abstract: Accurate biomass estimations are important for assessing and monitoring forest carbon storage. Bayesian theory has been widely applied to tree biomass models. Recently, a hierarchical Bayesian approach has received increasing attention for improving biomass models. In this study, tree biomass data were obtained by sampling 310 trees from 209 permanent sample plots from larch plantations in six regions across China. Non-hierarchical and hierarchical Bayesian approaches were used to model allometric biomass equations. We found that the total, root, stem wood, stem bark, branch and foliage biomass model relationships were statistically significant (p-values < 0.001) for both the non-hierarchical and hierarchical Bayesian approaches, but the hierarchical Bayesian approach increased the goodness-of-fit statistics over the non-hierarchical Bayesian approach. The R2 values of the hierarchical approach were higher than those of the non-hierarchical approach by 0.008, 0.018, 0.020, 0.003, 0.088 and 0.116 for the total tree, root, stem wood, stem bark, branch and foliage models, respectively. The hierarchical Bayesian approach significantly improved the accuracy of the biomass model (except for the stem bark) and can reflect regional differences by using random parameters to improve the regional scale model accuracy.
      PubDate: 2016-01-11
      DOI: 10.3390/f7010018
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 19: Environmental Drivers of Patterns of Plant
           

    • Authors: Chang-Bae Lee, Jung-Hwa Chun
      First page: 19
      Abstract: Understanding patterns of biodiversity and their drivers along environmental gradients is one of the central topics in ecology. However, whether diversity patterns along environmental gradients differ among diversity components as well as life forms and what kind of variables control or interact to shape the diversity patterns are poorly known. This study scrutinized the distribution patterns of three plant groups with four diversity indices and evaluated the effects of regional area, topography, topographic heterogeneity, climate, primary productivity, vegetation structure diversity and vegetation type diversity along an extensive elevational gradient on the Baekdudaegan Mountains in South Korea. Different elevational patterns, including hump-shaped, reversed hump-shaped, increasing, multimodal and no relationship, were observed among both the diversity indices and the plant groups. Regional area, habitat heterogeneity and climate were included to explain most of the elevational diversity patterns. In particular, habitat heterogeneity was the most important variable for explaining the patterns of diversity. The results suggest that patterns of elevational diversity may differ not only among plant groups but also among diversity indices and that such patterns are primarily caused by habitat heterogeneity in the Baekdudaegan Mountains because more heterogeneous and diverse habitats can support more coexisting species.
      PubDate: 2016-01-12
      DOI: 10.3390/f7010019
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 20: Quantifying the Impacts of Systemic Acquired
           Resistance to Pitch Canker on Monterey Pine Growth Rate and Hyperspectral
           Reflectance

    • Authors: Gregory Reynolds, Thomas Gordon, Neil McRoberts
      First page: 20
      Abstract: Pitch canker, caused by Fusarium circinatum, is a disease affecting Monterey pine (Pinus radiata) and many other pine species throughout the world. The impact of pitch canker on Pinus radiata may be limited by systemic acquired resistance (SAR), a phenomenon that elevates resistance to a pathogen after initial challenge by that pathogen or another microorganism. Allocation of resources to defense, as a consequence of SAR, is presumed to reduce resources available to support growth and reproduction, but specific fitness consequences associated with SAR in P. radiata have not been measured. To quantify impacts of SAR on growth rate, a 2 × 2 factorial experiment was established in which trees were either primed for SAR or unprimed, with half the trees in each of those two groups being inoculated with the pitch canker pathogen and the other half not inoculated. Priming for SAR was accomplished by inoculating one branch with F. circinatum and removing inoculated branches prior to subsequent challenge inoculations (= disease treatments). Disease treatments included three inoculations that were removed for measurement of lesion length, and three additional inoculations that remained on the tree as a representation of persistent disease. Control trees were mock inoculated with water. Main effects of priming and disease did not result in significant effects on growth rate. Based on hyperspectral canopy reflectance data, diseased trees were associated with higher difference vegetation index values and biomass. The absence of a negative impact on growth rate associated with SAR suggests that induction of resistance may have utility as a tool for management of pitch canker in plantations.
      PubDate: 2016-01-12
      DOI: 10.3390/f7010020
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 21: Community Structure, Biodiversity, and
           Ecosystem Services in Treeline Whitebark Pine Communities: Potential
           Impacts from a Non-Native Pathogen

    • Authors: Diana Tomback, Lynn Resler, Robert Keane, Elizabeth Pansing, Andrew Andrade, Aaron Wagner
      First page: 21
      Abstract: Whitebark pine (Pinus albicaulis) has the largest and most northerly distribution of any white pine (Subgenus Strobus) in North America, encompassing 18° latitude and 21° longitude in western mountains. Within this broad range, however, whitebark pine occurs within a narrow elevational zone, including upper subalpine and treeline forests, and functions generally as an important keystone and foundation species. In the Rocky Mountains, whitebark pine facilitates the development of krummholz conifer communities in the alpine-treeline ecotone (ATE), and thus potentially provides capacity for critical ecosystem services such as snow retention and soil stabilization. The invasive, exotic pathogen Cronartium ribicola, which causes white pine blister rust, now occurs nearly rangewide in whitebark pine communities, to their northern limits. Here, we synthesize data from 10 studies to document geographic variation in structure, conifer species, and understory plants in whitebark pine treeline communities, and examine the potential role of these communities in snow retention and regulating downstream flows. Whitebark pine mortality is predicted to alter treeline community composition, structure, and function. Whitebark pine losses in the ATE may also alter response to climate warming. Efforts to restore whitebark pine have thus far been limited to subalpine communities, particularly through planting seedlings with potential blister rust resistance. We discuss whether restoration strategies might be appropriate for treeline communities.
      PubDate: 2016-01-19
      DOI: 10.3390/f7010021
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 22: A Global Index for Mapping the Exposure of
           Water Resources to Wildfire

    • First page: 22
      Abstract: Wildfires are keystone components of natural disturbance regimes that maintain ecosystem structure and functions, such as the hydrological cycle, in many parts of the world. Consequently, critical surface freshwater resources can be exposed to post-fire effects disrupting their quantity, quality and regularity. Although well studied at the local scale, the potential extent of these effects has not been examined at the global scale. We take the first step toward a global assessment of the wildfire water risk (WWR) by presenting a spatially explicit index of exposure. Several variables related to fire activity and water availability were identified and normalized for use as exposure indicators. Additive aggregation of those indicators was then carried out according to their individual weight. The resulting index shows the greatest exposure risk in the tropical wet and dry forests. Intermediate exposure is indicated in mountain ranges and dry shrublands, whereas the lowest index scores are mostly associated with high latitudes. We believe that such an approach can provide important insights for water security by guiding global freshwater resource preservation.
      PubDate: 2016-01-13
      DOI: 10.3390/f7010022
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 23: A Quantitative Assessment of Forest Cover
           Change in the Moulouya River Watershed (Morocco) by the Integration of a
           Subpixel-Based and Object-Based Analysis of Landsat Data

    • First page: 23
      Abstract: A quantitative assessment of forest cover change in the Moulouya River watershed (Morocco) was carried out by means of an innovative approach from atmospherically corrected reflectance Landsat images corresponding to 1984 (Landsat 5 Thematic Mapper) and 2013 (Landsat 8 Operational Land Imager). An object-based image analysis (OBIA) was undertaken to classify segmented objects as forested or non-forested within the 2013 Landsat orthomosaic. A Random Forest classifier was applied to a set of training data based on a features vector composed of different types of object features such as vegetation indices, mean spectral values and pixel-based fractional cover derived from probabilistic spectral mixture analysis). The very high spatial resolution image data of Google Earth 2013 were employed to train/validate the Random Forest classifier, ranking the NDVI vegetation index and the corresponding pixel-based percentages of photosynthetic vegetation and bare soil as the most statistically significant object features to extract forested and non-forested areas. Regarding classification accuracy, an overall accuracy of 92.34% was achieved. The previously developed classification scheme was applied to the 1984 Landsat data to extract the forest cover change between 1984 and 2013, showing a slight net increase of 5.3% (ca. 8800 ha) in forested areas for the whole region.
      PubDate: 2016-01-15
      DOI: 10.3390/f7010023
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 24: Exploring Opportunities for Promoting Synergies
           between Climate Change Adaptation and Mitigation in Forest Carbon
           Initiatives

    • Authors: Eugene Chia, Kalame Fobissie, Markku Kanninen
      First page: 24
      Abstract: There is growing interest in designing and implementing climate change mitigation and adaptation (M + A) in synergy in the forest and land use sectors. However, there is limited knowledge on how the planning and promotion of synergies between M + A can be operationalized in the current efforts to mitigate climate change through forest carbon. This paper contributes to fill this knowledge gap by exploring ways of planning and promoting M + A synergy outcomes in forest carbon initiatives. It examines eight guidelines that are widely used in designing and implementing forest carbon initiatives. Four guiding principles with a number of criteria that are relevant for planning synergy outcomes in forest carbon activities are proposed. The guidelines for developing forest carbon initiatives need to demonstrate that (1) the health of forest ecosystems is maintained or enhanced; (2) the adaptive capacity of forest-dependent communities is ensured; (3) carbon and adaptation benefits are monitored and verified; and (4) adaptation outcomes are anticipated and planned in forest carbon initiatives. The forest carbon project development guidelines can encourage the integration of adaptation in forest carbon initiatives. However, their current efforts guiding projects and programs to deliver biodiversity and environmental benefits, ecosystem services, and socioeconomic benefits are not considered explicitly as efforts towards enhancing adaptation. An approach for incentivizing and motivating project developers, guideline setters, and offset buyers is imperative in order to enable existing guidelines to make clear contributions to adaptation goals. We highlight and discuss potential ways of incentivizing and motivating the explicit planning and promotion of adaptation outcomes in forest carbon initiatives.
      PubDate: 2016-01-15
      DOI: 10.3390/f7010024
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 25: Synthesis and New Observations on Needle
           Pathogens of Larch in Northern Finland

    • Authors: Risto Jalkanen
      First page: 25
      Abstract: Needle pathogens of larch (Larix spp.) in the Nordic countries are under-studied. Their incidence in Finland tends to be low and local, and this may be a function of enemy release, since species of larch were introduced to the region. Here, the ecology and incidence of larch needle pathogens and the abiotic factors that also affect larch in northern Finland are reviewed. Field observations and related laboratory analyses during the past 35 years have mainly been obtained near the Kivalo Research Area within the Arctic Circle, Finnish Lapland. The relatively recent introduction of Hypodermella laricis is a primary focus. This pathogen is not only new to Nordic countries, but can cause severe outbreaks, defoliation and crown-thinning in the canopies of all ages of most planted larch species worldwide. Symptoms of H. laricis clearly differ from those of Mycosphaerella laricina; the latter has affected Larix sibirica at high latitudes for decades. The effects of Meria laricis, Lophodermium laricinum, various rust fungi, and wind and frost are also discussed.
      PubDate: 2016-01-18
      DOI: 10.3390/f7010025
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 26: Acknowledgement to Reviewers of Forests in 2015

    • Authors: Forests Editorial Office
      First page: 26
      Abstract: The editors of Forests would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2015. [...]
      PubDate: 2016-01-22
      DOI: 10.3390/f7010026
      Issue No: Vol. 7, No. 1 (2016)
       
  • Forests, Vol. 7, Pages 1: Detection of Airborne Inoculum of Hymenoscyphus
           fraxineus and H. albidus during Seasonal Fluctuations Associated with
           Absence of Apothecia

    • Authors: Milon Dvorak, Gabriela Rotkova, Leticia Botella
      First page: 1
      Abstract: Hymenoscyphus fraxineus is an invasive fungal species causing the most serious disease of ashes (Fraxinus spp.) in Europe—ash dieback. The biology of this fungus is not totally elucidated, neither its relation to the saprophytic species Hymenoscyphus albidus, native in Europe. Our study is focused on the description of seasonal spore dispersal of both fungi and its relation to meteorological conditions, which is needed for more precise and effective control of the disease. For this experiment one long time infected mixed forest in the SE Czech Republic was chosen. A seven-day automatic volumetric spore trap and a weather station were installed to continuously sample the aerospora from April to October 2014. In seven periods a rotating arm spore trap was also used to obtain 48-h air samples to compare the efficiency of these two types of air samplers. Air samples were evaluated solely by qPCR with a very low detection limit. Results show co-occurrence of inoculum of both fungi throughout the entire sampling period with peak levels in August. The origin of the inoculum sampled in the periods without apothecia is discussed. Air-inoculum occurrence of both fungi is significantly correlated with each other, suggesting their coexistence in this forest.
      PubDate: 2015-12-22
      DOI: 10.3390/f7010001
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 2: Responses of Clonal Eucalypt Plantations to N, P
           and K Fertilizer Application in Different Edaphoclimatic Conditions

    • First page: 2
      Abstract: Eucalypt plantations in Brazil have the highest mean productivity when compared to other producing countries, and fertilizer application is one of the main factors responsible for these productivities. Our aim was to identify appropriate rates of N, P and K in eucalypt plantations and their interactions with edaphoclimatic factors. Four trials with four rates and three nutrients (N, P and K) were set up. Each nutrient was studied separately, and the trees received sufficient rates of all of the other nutrients through fertilization, to avoid limitations not related to the desired nutrient. We assessed solid wood volume (SV), productivity gains (PG), leaf nutrient content and leaf area index (LAI) to determine the responses to fertilization. PG, regarding N, rates ranged from 104% to 127% at 60 months after planting. P fertilizer application led to gains in productivity in soils with levels of P-resin up to 5 mg·kg−1, but decreased with stand age. K fertilizer application responses increased within age in three sites. In Paulistania, responses to K application were close to zero. N and K responses were climate related. Leaf nutrient content and LAI were not able to predict the highest yields obtained.
      PubDate: 2015-12-22
      DOI: 10.3390/f7010002
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 3: The Interaction between FSC Certification and
           the Implementation of the EU Timber Regulation in Romania

    • Authors: Ines Gavrilut, Aureliu-Florin Halalisan, Alexandru Giurca, Metodi Sotirov
      First page: 3
      Abstract: This explorative study aims to shed light on the ways in which Forest Stewardship Council (FSC) certification interacts with the implementation of the EU Timber Regulation (EUTR) in Romania. To this end, the EUTR implementation process is examined, and the relationship between this implementation and FSC certification is explored. There is a particular focus on the extent to which certification has helped companies to comply with EUTR requirements. The study uses the analytical framework of Transnational Business Governance Interactions (TBGI) and a mixed research approach. It is found that FSC certification has to a large extent helped companies to prepare for and align with the EUTR’s requirements, in particular concerning risk assessment and risk mitigation procedures needed for a due diligence system (DDS), and in the context of a “policy vacuum” period related to EUTR implementation. Moreover, recent changes in the FSC standard make it theoretically in line with EUTR requirements. However, difficulties remain in relation to the lack of information, costs and bureaucracy associated with both EUTR implementation and FSC certification. Notably, in the absence of a monitoring organization, the establishment of a viable DDS is still problematic as many companies remain unprepared for developing their own systems. Finally, the EUTR and its risk management requirements may have partly fueled the increase in uptake of chain of custody (CoC) certification in Romania. However, due to the risk of CoC certificates including illegally sourced timber, this recent uptake in certification does not necessarily indicate improved sustainable forest management (SFM) or full compliance with EUTR.
      PubDate: 2015-12-22
      DOI: 10.3390/f7010003
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 4: Consequences of Shifts in Abundance and
           Distribution of American Chestnut for Restoration of a Foundation Forest
           Tree

    • Authors: Harmony Dalgleish, C. Nelson, John Scrivani, Douglass Jacobs
      First page: 4
      Abstract: Restoration of foundation species, such as the American chestnut (Castanea dentata) that was devastated by an introduced fungus, can restore ecosystem function. Understanding both the current distribution as well as biogeographic patterns is important for restoration planning. We used United States Department of Agriculture Forest Service Forest Inventory and Analysis data to quantify the current density and distribution of C. dentata. We then review the literature concerning biogeographic patterns in C. dentata. Currently, 431 ± 30.2 million stems remain. The vast majority (360 ± 22 million) are sprouts <2.5 cm dbh. Although this number is approximately 10% of the estimated pre-blight population, blight has caused a major shift in the size structure. The current-day population has a larger range, particularly west and north, likely due to human translocation. While climate change could facilitate northward expansion, limited seed reproduction makes this unlikely without assisted migration. Previous research demonstrates that the current, smaller population contains slightly higher genetic diversity than expected, although little information exists on biogeographic patterns in the genetics of adaptive traits. Our research provides a baseline characterization of the contemporary population of C. dentata, to enable monitoring stem densities and range limits to support restoration efforts.
      PubDate: 2015-12-24
      DOI: 10.3390/f7010004
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 5: Managed Mixtures of Aspen and White Spruce 21 to
           25 Years after Establishment

    • Authors: Richard Kabzems, Mike Bokalo, Philip Comeau, Daniel MacIsaac
      First page: 5
      Abstract: Intimate mixtures of trembling aspen (Populus tremuloides Michx.) and white spruce (Picea glauca (Moench) Voss) are a key feature of western Canadian boreal forests. These mixtures have the potential to produce high yields of merchantable fibre and provide numerous ecological services. Achievement of this potential has been difficult, and often expensive, to realize as a regeneration goal in managed forests. We report 21 to 25 year results of managed mixtures on two study sites where the white spruce was planted, and the density of aspen natural regeneration manipulated within five years of the stand initiation disturbance. On both sites, white spruce mortality did not increase with increasing aspen density. While height and diameter growth of white spruce declined with increasing aspen density, the effect was not entirely consistent across the two sites. Abrasion from aspen branches was the most common source of damage to spruce crowns. Mixed stands had greater merchantable volume production than pure spruce stands based on model projections. Application of aspen harvest at year 60, while protecting the spruce component for a second harvest entry at year 90, was projected to optimize combined yield for the mixedwood stands.
      PubDate: 2015-12-24
      DOI: 10.3390/f7010005
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 6: Streamflow Regime Variations Following
           Ecological Management on the Loess Plateau, China

    • Authors: Jianjun Zhang, Tingting Zhang, Yongnan Lei, Xiaoping Zhang, Rui Li
      First page: 6
      Abstract: The continuous ecological management of the Loess Plateau is known throughout the world for two strategies: the integrated soil conservation project that began in the 1970s, and the “Grain for Green” project that began in the 1990s. Six sub-catchments nested in the Beiluo River basin were selected to investigate streamflow regime variations during the two project periods. The annual streamflow trends and change points were detected using a bootstrap-based Mann-Kendall test and Pettitt test. Annual streamflow (from the 1950s to 2011) exhibited significantly negative trends in five out of six catchments, varying from −0.15 to −0.30 mm/a. During the integrated soil conservation period, the annual streamflow was reduced due to high flow decreases (5% of time exceeded), whereas in the low flows (95%) it increased in all sub-catchments. During the “Grain for Green” period, the annual streamflow decreased due to daily streamflow reductions at four stations. In addition to high flow and low flow decreases at the Wuqi and Liujiahe stations during the “Grain for Green” period, it is significant that the low flows continuously increased. Compared with trends from the forestry area, which includes the Zhangcunyi and Huangling stations, incremental annual streamflow reductions were observed in other sub-catchments, which can be linked to ecological management. This result implies that streamflow can be moderated by appropriate management options, even in semiarid areas. It was concluded that a stable streamflow regime can be achieved in vegetated areas, and streamflow moderation is dependent on ecological management practices.
      PubDate: 2015-12-25
      DOI: 10.3390/f7010006
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 7: Delphinella Shoot Blight on Abies lasiocarpa
           Provenances in Norway

    • First page: 7
      Abstract: Delphinella shoot blight (Delphinella abietis) attacks true firs (Abies spp.) in Europe and North America. Especially subalpine fir (A. lasiocarpa), one of the main Christmas tree species in Norway, is prone to the disease. The fungus kills current year needles, and in severe cases entire shoots. Dead needles become covered with black fruiting bodies, both pycnidia and pseudothecia. Delphinella shoot blight has mainly been a problem in humid, coastal regions in the northwestern part of Southern Norway, but, probably due to higher precipitation in inland regions during recent years, heavy attacks were found in 2011 in a field trial with 76 provenances of subalpine fir in Southeastern Norway. However, the amount of precipitation seemed less important once the disease had established in the field. Significant differences in susceptibility between provenances were observed. In general, the more bluish the foliage was, the healthier the trees appeared. The analysis of provenance means indicated that, at least for the southern range, the disease ratings were correlated with foliage color. This study also includes isolation, identification, a pathogenicity test, a seed test and electron microscopy of the wax layer on the needles. The fungus was identified based on the morphology of spores and by sequencing the Internal Transcribed Spacer (ITS) regions of the ribosomal DNA. Koch’s postulates were fulfilled. The fungus was found present on newly harvested seeds and may therefore spread via international seed trade. When comparing the wax layers on green and blue needles, those of the latter were significantly thicker, a factor that may be involved in disease resistance.
      PubDate: 2015-12-25
      DOI: 10.3390/f7010007
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 8: Adaptation of Forest Management Regimes in
           Southern Sweden to Increased Risks Associated with Climate Change

    • First page: 8
      Abstract: Even though the growth rates of most tree species in Sweden is expected to increase in the near future as a result of climate change, increased risks of damage by storms and various pests and pathogens, notably root rot and bark beetles, may also occur. Thus, forest management practices such as changes to thinning regimes, reductions in rotation lengths, and switching to other species (native or exotic) may represent adaptive management strategies to increase the resistance and resilience of Swedish forests to climate change. Clearly, thorough analyses examining the effects of anticipated climatic changes on damage levels, and the potentially relieving effects of possible management adaptations are needed before implementing such changes. In this study, damage caused by storms, root rot and bark beetles (single and in various combinations) under selected climate and management scenarios were simulated in Norway spruce (Pice abies L. Karst) stands. The results indicate that reductions in thinning intensity and rotation lengths could improve both volume production and profitability in southern Sweden. In addition, cultivation of rapidly growing species, such as hybrid larch (Larix × marschlinsii Coaz.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.), could be as profitable as Norway spruce cultivation, or even more profitable. However, slow-growing species, such as Silver birch (Betula pendula Roth), Downy birch (Betula pubescens Ehrh.) and European beech (Fagus sylvatica L.) indicated low economic output in terms of Land Expectation Value.
      PubDate: 2015-12-25
      DOI: 10.3390/f7010008
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 9: Foundation Species Loss and Biodiversity of the
           Herbaceous Layer in New England Forests

    • Authors: Aaron Ellison, Audrey Barker Plotkin, Shah Khalid
      First page: 9
      Abstract: Eastern hemlock (Tsuga canadensis) is a foundation species in eastern North American forests. Because eastern hemlock is a foundation species, it often is assumed that the diversity of associated species is high. However, the herbaceous layer of eastern hemlock stands generally is sparse, species-poor, and lacks unique species or floristic assemblages. The rapidly spreading, nonnative hemlock woolly adelgid (Adelges tusgae) is causing widespread death of eastern hemlock. Loss of individual hemlock trees or whole stands rapidly leads to increases in species richness and cover of shrubs, herbs, graminoids, ferns, and fern-allies. Naively, one could conclude that the loss of eastern hemlock has a net positive effect on biodiversity. What is lost besides hemlock, however, is landscape-scale variability in the structure and composition of the herbaceous layer. In the Harvard Forest Hemlock Removal Experiment, removal of hemlock by either girdling (simulating adelgid infestation) or logging led to a proliferation of early-successional and disturbance-dependent understory species. In other declining hemlock stands, nonnative plant species expand and homogenize the flora. While local richness increases in former eastern hemlock stands, between-site and regional species diversity will be further diminished as this iconic foundation species of eastern North America succumbs to hemlock woolly adelgid.
      PubDate: 2015-12-25
      DOI: 10.3390/f7010009
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 7, Pages 10: Modeling Ecohydrological Processes and Spatial
           Patterns in the Upper Heihe Basin in China

    • Authors: Bing Gao, Yue Qin, Yuhan Wang, Dawen Yang, Yuanrun Zheng
      First page: 10
      Abstract: The Heihe River is the second largest inland basin in China; runoff in the upper reach greatly affects the socio-economic development in the downstream area. The relationship between spatial vegetation patterns and catchment hydrological processes in the upper Heihe basin has remained unclear to date. In this study, a distributed ecohydrological model is developed to simulate the hydrological processes with vegetation dynamics in the upper Heihe basin. The model is validated by hydrological observations at three locations and soil moisture observations at a watershed scale. Based on the simulated results, the basin water balance characteristics and their relationship with the vegetation patterns are analyzed. The mean annual precipitation and runoff increase with the elevation in a similar pattern. Spatial patterns of the actual evapotranspiration is mainly controlled by the precipitation and air temperature. At the same time, vegetation distribution enhances the spatial variability of the actual evapotranspiration. The highest actual evapotranspiration is around elevations of 3000–3600 m, where shrub and alpine meadow are the two dominant vegetation types. The results show the mutual interaction between vegetation dynamics and hydrological processes. Alpine sparse vegetation and alpine meadow dominate the high-altitude regions, which contribute most to the river runoff, and forests and shrub contribute relatively small amounts of water yield.
      PubDate: 2015-12-25
      DOI: 10.3390/f7010010
      Issue No: Vol. 7, No. 1 (2015)
       
  • Forests, Vol. 6, Pages 3353-3368: Impact of Seed Transmission on the
           Infection and Development of Pitch Canker Disease in Pinus radiata

    • Authors: Margarita Evira-Recuenco, Eugenia Iturritxa, Rosa Raposo
      Pages: 3353 - 3368
      Abstract: The aim of this study was to determine the impact of seed inoculum on subsequent disease development in nurseries, specifically studying incidence of seed infection, transmission rate of seed to seedlings, and rate of disease development from the primary inoculum source. Transmission rate of Fusarium circinatum (F. circinatum) from symptomatic trees of Pinus radiata (P. radiata) to seed was 0.73%, being the fungus mainly on the coat. Seed infection incidence was positively correlated with tree disease severity. Seeds also become contaminated with F. circinatum during storage, where high relative humidity had a great effect regardless of temperature. Transmission rates from seeds to symptomatic seedlings measured at 48 days after seed inoculation with 104 and 106 was 28% and 80%, respectively. Seedlings showed symptoms of wilting and dieback, and eventually died within the total duration of this study (475 days). By this time, there were two remaining symptomless seedlings (1% of the total). F. circinatum was recovered from each of them, demonstrating its persistence in seedlings. Fungus populations in roots were estimated between 105 and 107 cfu/g in symptomatic plants for both inoculum doses and up to 104 cfu/g in asymptomatic plants. Disease infection rate was similar in post-emergence damping-off (up two months growing) and for established seedlings (up to eight months) after seeds were inoculated with 104 spores/mL.
      PubDate: 2015-09-23
      DOI: 10.3390/f6093353
      Issue No: Vol. 6, No. 9 (2015)
       
  • Forests, Vol. 6, Pages 4374-4390: Species Distribution Model for
           Management of an Invasive Vine in Forestlands of Eastern Texas

    • Authors: Hsiao-Hsuan Wang, Tomasz Koralewski, Erin McGrew, William Grant, Thomas Byram
      First page: 4374
      Abstract: Invasive plants decrease biodiversity, modify vegetation structure, and inhibit growth and reproduction of native species. Japanese honeysuckle (Lonicera japonica Thunb.) is the most prevalent invasive vine in the forestlands of eastern Texas. Hence, we aimed to identify potential factors influencing the distribution of the species, quantify the relative importance of each factor, and test possible management strategies. We analyzed an extensive dataset collected as part of the Forest Inventory and Analysis Program of the United States Department of Agriculture (USDA) Forest Service to quantify the range expansion of Japanese honeysuckle in the forestlands of eastern Texas from 2006 to 2011. We then identified potential factors influencing the likelihood of presence of Japanese honeysuckle using boosted regression trees. Our results indicated that the presence of Japanese honeysuckle on sampled plots almost doubled during this period (from 352 to 616 plots), spreading extensively, geographically. The probability of invasion was correlated with variables representing landscape conditions, climatic conditions, forest features, disturbance factors, and forest management activities. Habitats most at risk to invasion under current conditions occurred primarily in northeastern Texas, with a few invasion hotspots in the south. Estimated probabilities of invasion were reduced most by artificial site regeneration, with habitats most at risk again occurring primarily in northeastern Texas.
      PubDate: 2015-11-27
      DOI: 10.3390/f6124374
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4391-4402: The Impact of Changes in Species
           Richness and Species Replacement on Patterns of Taxonomic Homogenization
           in the Carpathian Forest Ecosystems

    • First page: 4391
      Abstract: The Carpathians are Eastern Europe’s largest contiguous forest ecosystem and a hotspot of biodiversity. However, not much is known about changes in species diversity in these forests. Here we investigate the long-time changes in the diversity of plant communities in the Eastern Carpathian beech forests. We also inquire about the similarity of plant communities between managed and protected forests. We conduct our analyses using not only the broad-sense measure of changes in β diversity (βsor) but also the measures that reveal whether the changes result from spatial turnover (βsim) or nestedness (βnes). Our study demonstrated that the mean species richness did not significantly change over time in both forest types. However, we found a significant decrease of species diversity in protected forests and the same trend, but on a smaller scale, in managed forests. In both forest types the decrease of species diversity was mainly caused by spatial turnover, while nestedness-related changes were relatively small. However, the direction of changes in βnes differed in managed and unmanaged forests in such a way that it reduced the decrease of species diversity in managed forests and amplified the decrease of species diversity in unmanaged forests. We discuss our findings in terms of biotic homogenization.
      PubDate: 2015-11-30
      DOI: 10.3390/f6124376
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4403-4420: Prioritization of Forest Restoration
           Projects: Tradeoffs between Wildfire Protection, Ecological Restoration
           and Economic Objectives

    • Authors: Kevin Vogler, Alan Ager, Michelle Day, Michael Jennings, John Bailey
      First page: 4403
      Abstract: The implementation of US federal forest restoration programs on national forests is a complex process that requires balancing diverse socioecological goals with project economics. Despite both the large geographic scope and substantial investments in restoration projects, a quantitative decision support framework to locate optimal project areas and examine tradeoffs among alternative restoration strategies is lacking. We developed and demonstrated a new prioritization approach for restoration projects using optimization and the framework of production possibility frontiers. The study area was a 914,657 ha national forest in eastern Oregon, US that was identified as a national priority for restoration with the goal of increasing fire resiliency and sustaining ecosystem services. The results illustrated sharp tradeoffs among the various restoration goals due to weak spatial correlation of forest stressors and provisional ecosystem services. The sharpest tradeoffs were found in simulated projects that addressed either wildfire risk to the urban interface or wildfire hazard, highlighting the challenges associated with meeting both economic and fire protection goals. Understanding the nature of tradeoffs between restoration objectives and communicating them to forest stakeholders will allow forest managers to more effectively design and implement economically feasible restoration projects.
      PubDate: 2015-12-01
      DOI: 10.3390/f6124375
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4421-4438: Applying Resilience Concepts in Forest
           Management: A Retrospective Simulation Approach

    • Authors: Caren Dymond, David Spittlehouse, Sinclair Tedder, Katherine Hopkins, Katharine McCallion, James Sandland
      First page: 4421
      Abstract: Increasing the resilience of ecological and sociological systems has been proposed as an option to adapt to changing future climatic conditions. However, few studies test the applicability of those strategies to forest management. This paper uses a real forest health incident to assess the ability of forest management strategies to affect ecological and economic resilience of the forest. Two landscape scale strategies are compared to business as usual management for their ability to increase resilience to a climate-change induced mountain pine beetle outbreak in the Kamloops Timber Supply Area, British Columbia, Canada for the period 1980 to 2060. Proactive management to reduce high risk species while maintaining or increasing diversity through reforestation was found to be more resilient in terms of the metrics: post-disturbance growing stock, improved volume and stability of timber flow, and net revenue. However, landscape-scale indicators of diversity were little affected by management. Our results were robust to uncertainty in tree growth rates and timber value and show that adapting to climate change through improving the resilience of forested landscapes is an economically viable option.
      PubDate: 2015-12-01
      DOI: 10.3390/f6124377
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4439-4450: Effects of Stand Origin and Near-Natural
           Restoration on the Stock and Structural Composition of Fallen Trees in
           Mid-Subtropical Forests

    • Authors: Chunsheng Wu, Xiaohua Wei, Qifeng Mo, Qinglin Li, Xiaodong Li, Chunjie Shu, Liangying Liu, Yuanqiu Liu
      First page: 4439
      Abstract: Fallen trees comprise an important part of forest ecosystems and serve a central role in maintaining the biodiversity and tree regeneration of forests. However, the effects of stand origin and near-natural restoration on the biomass and carbon stock of fallen trees remain unclear. Based on 60 sampling plots of field surveys of mid-subtropical forests in Jiangxi Province, we investigated the stock and structural composition of fallen trees in artificial coniferous forests (Acf), natural coniferous forests (Ncf) (e.g., different stand origins) and natural evergreen broadleaf forests (Nebf) (e.g., near-natural restoration). The following results were obtained: (1) the largest biomass and carbon stocks of fallen trees among three forest types (Nebf, Ncf and Acf) were measured for Nebf; (2) the fallen tree biomass and carbon stock in natural Cunninghamia lanceolata forest (Nclf) were significantly larger than that in artificial Cunninghamia lanceolata forest (Aclf), and the fallen tree biomass and carbon stock in natural Pinus massoniana forest (Npf) were also significantly larger than those in artificial Pinus massoniana forest (Apf); (3) the diameter class allocation in natural forests was more uniform than that in artificial forests; (4) the biomass of fallen trees with mild decay was not significantly different among forest types within stand origin or among the stand origin within forest types; however, the biomass of fallen trees with moderate and heavy decay significantly differed among stand origin (Aclf vs. Nclf, Apf vs. Npf), but was not significant among the forest types (Aclf vs. Apf, Nclf vs. Apf) within a stand origin. Our results suggested that the large biomass and carbon stock of fallen trees in Nebf may serve a significant role in mitigating global warming and carbon cycles in mid-subtropical forests. Therefore, stand origin and near-natural restoration exert significant effects on the carbon stock and structural composition of fallen trees in mid-subtropical forests.
      PubDate: 2015-12-03
      DOI: 10.3390/f6124380
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4451-4461: Tree Species Establishment in Urban
           Forest in Relation to Vegetation Composition, Tree Canopy Gap Area and
           Soil Factors

    • First page: 4451
      Abstract: The study of density and growth of pine, birch and oak seedlings and saplings in canopy gaps in the urban boreal forest in Riga, Latvia, indicates that natural regeneration can increase diversity in small gaps caused by tree mortality, and can ensure conversion from even-aged pine forest. Abundant regeneration in small gaps showed that light (gap area) was only one of the factors affecting tree regeneration in the gaps. The depth of the O layer and pH were suggested to be important factors for the establishment and growth of pine and birch. For oak, the main factors for establishment and growth were favorable moisture, higher pH and N concentration. Knowledge of ecological factors affecting the establishment of seedlings and growth of saplings of the most common trees species in the urban boreal forest is needed to predict successional trajectories and to aid management.
      PubDate: 2015-12-04
      DOI: 10.3390/f6124379
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4462-4476: Effects of Nitrogen Addition on Leaf
           Decomposition of Single-Species and Litter Mixture in Pinus tabulaeformis
           Forests

    • Authors: Jinsong Wang, Wensheng Bu, Bo Zhao, Xiuhai Zhao, Chunyu Zhang, Juan Fan, Klaus Gadow
      First page: 4462
      Abstract: The litter decomposition process is closely correlated with nutrient cycling and the maintenance of soil fertility in the forest ecosystem. In particular, the intense environmental concern about atmospheric nitrogen (N) deposition requires a better understanding of its influence on the litter decomposition process. This study examines the responses of single-species litter and litter mixture decomposition processes to N addition in Chinese pine (Pinus tabulaeformis Carr.) ecosystems. Chinese pine litter, Mongolian oak (Quercus mongolica Fisch. ex Ledeb.) litter, and a pine–oak mixture were selected from a plantation and a natural forest of Chinese pine. Four N addition treatments, i.e., control (N0: 0 kg N ha−1·year−1), low-N (N1: 5 kg N ha−1·year−1), medium-N (N2: 10 kg N ha−1·year−1), and high-N (N3: 15 kg N ha−1·year−1), were applied starting May 2010. In the plantation, N addition significantly stimulated the decomposition of the Chinese pine litter. In the natural forest, N addition had variable effects on the decomposition of single-species litter and the litter mixture. A stimulatory effect of the high-N treatment on the Chinese pine litter decomposition could be attributed to a decrease in the substrate C:N ratio. However, an opposite effect was found for the Mongolian oak litter decomposition. The stimulating effect of N addition on the Chinese pine litter may offset the suppressive effect on the Mongolian oak litter, resulting in a neutral effect on the litter mixture. These results suggest that the different responses in decomposition of single-species litter and the litter mixture to N addition are mainly attributed to litter chemical composition. Further investigations are required to characterize the effect of long-term high-level N addition on the litter decomposition as N deposition is likely to increase rapidly in the region where this study was conducted.
      PubDate: 2015-12-04
      DOI: 10.3390/f6124381
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4477-4494: Restoring and Conserving Khasi Forests:
           A Community-Based REDD Strategy from Northeast India

    • Authors: Mark Poffenberger
      First page: 4477
      Abstract: An initiative to Reduce Emissions from Deforestation and Forest Degradation (REDD) was launched in December 2007 at the Bali Conference of Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC), yet little progress has been made in Asia in developing certified REDD projects, especially those that engage forest-dependent people. According to UNFCCC, REDD is a multilevel activity that involves both national policy and structures, as well as subnational projects involving local communities [1]. While many Asian nations are trying to create frameworks that link the national strategy to sub-national projects, in India this formal integration has yet to take place. As a consequence projects like the Khasi Hills Community REDD+ project fall outside the UNFCCC strategy and operate under voluntary standards (Plan Vivo) and markets. The project involves both avoided deforestation and reforestation components. The project is being implemented by a federation of ten Khasi tribal kingdoms, a major ethnolinguistic group in the Indian state of Meghalaya. Project experience may provide guidance regarding actions required to create a more enabling environment for community forest carbon projects in Asia. These findings may better inform the December 2015 21st UNFCCC Conference of Parties in Paris as they again address REDD strategy. The experience of this Khasi Federation [2] in designing and implementing a REDD project has led to the emergence of a modernizing forest management system that is helping to conserve and restore the Khasi’s ancestral forests. Learning from this REDD project also illustrates the barriers that the Khasi communities have faced, including those imposed by national governments, certifiers, and carbon markets, that will likely constrain the expansion and replication of community-based climate initiatives. The author suggests some alternative policies and systems that may enable greater community participation in REDD projects.
      PubDate: 2015-12-11
      DOI: 10.3390/f6124382
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4495-4509: Effects of Cutting Intensity on Soil
           Physical and Chemical Properties in a Mixed Natural Forest in Southeastern
           China

    • Authors: Xinnian Zhou, Yuan Zhou, Chengjun Zhou, Zhilong Wu, Lifeng Zheng, Xisheng Hu, Hanxian Chen, Jianbang Gan
      First page: 4495
      Abstract: The mixed Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), Masson’s pine (Pinus massoniana Lamb.), and hardwood forest is a major forest type in China and of national and international importance in terms of its provision of both timber and ecosystem services. However, over-harvesting has threatened its long-term productivity and sustainability. We examined the impacts of timber harvesting intensity on soil physical and chemical properties 10 and 15 years after cutting using the research plots established with a randomized block design. We considered five treatments, including clear cutting and low (13.0% removal of growing stock volume), medium (29.1%), high (45.8%), and extra-high (67.1) intensities of selective cutting with non-cutting as the control. The impact on overall soil properties derived from principal component analysis showed increasing with a rise in cutting intensity, and the most critical impact was on soil nutrients, P and K in particular. Soil nutrient loss associated with timber harvesting even at a low cutting intensity could lead to nutrient deficits in this forest although most of the soil physical properties could be recovered under the low and medium intensities of cutting. These results indicate that clear cutting and the selective cutting of extra-high and high intensities should be avoided in this type of forest in the region.
      PubDate: 2015-12-11
      DOI: 10.3390/f6124383
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4510-4528: Wall-to-Wall Forest Mapping Based on
           Digital Surface Models from Image-Based Point Clouds and a NFI Forest
           Definition

    • Authors: Lars Waser, Christoph Fischer, Zuyuan Wang, Christian Ginzler
      First page: 4510
      Abstract: Forest mapping is an important source of information for assessing woodland resources and a key issue for any National Forest Inventory (NFI). In the present study, a detailed wall-to-wall forest cover map was generated for all of Switzerland, which meets the requirement of the Swiss NFI forest definition. The workflow is highly automated and based on digital surface models from image-based point clouds of airborne digital sensor data. It fully takes into account the four key criteria of minimum tree height, crown coverage, width, and land use. The forest cover map was validated using almost 10,000 terrestrial and stereo-interpreted NFI plots, which verified 97% agreement overall. This validation implies different categories such as five production regions, altitude, tree type, and distance to the forest border. Overall accuracy was lower at forest borders but increased with increasing distance from the forest border. Commission errors remained stable at around 10%, but increased to 17.6% at the upper tree line. Omission errors were low at 1%–10%, but also increased with altitude and mainly occurred at the upper tree line (19.7%). The main reasons for this are the lower image quality and the NFI height definition for forest which apparently excludes shrub forest from the mask. The presented forest mapping approach is superior to existing products due to its national coverage, high level of detail, regular updating, and implementation of the land use criteria.
      PubDate: 2015-12-11
      DOI: 10.3390/f6124386
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4529-4539: Habitat Effect on Allometry of a Xeric
           Shrub (Artemisia ordosica Krasch) in the Mu Us Desert of Northern China

    • Authors: Weiwei She, Yuqing Zhang, Shugao Qin, Bin Wu, Zhen Liu, Jun Liu, Wenjin Zhang
      First page: 4529
      Abstract: Allometric models are useful for assessment of aboveground net primary productivity (ANPP) and aboveground biomass (AGB) of forests and shrubs, and are widely implemented in forest inventory and management. Multiple forms of allometric models have been used to estimate vegetation carbon storage for desert shrubland, but their validity for biomass estimation has not been tested at a region scale with different habitats. To verify the validity of habitat-specific models, general models (combining data from all habitats/sites), and previously developed models for biomass prediction, we developed both general models and habitat-specific models for aboveground biomass and ANPP of Artemisia ordosica Krasch, a dominant shrub of the Mu Us Desert. Our results showed that models based on crown area or canopy volume consistently explained large parts of the variations in aboveground biomass and ANPP. Model fitting highlighted that general allometric models were inadequate across different habitats, and habitat-specific models were useful for that specific habitat. Previous models might be inappropriate for other sites because of site quality differences. There was a strong habitat effect on the allometric relationships of A. ordosica. Although our study is a case in point, the results indicate that allometric models for desert shrubs should be used with caution and require robust validation if adopted from other studies or applied to different sites/habitats.
      PubDate: 2015-12-11
      DOI: 10.3390/f6124385
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4540-4557: Data Assimilation in Forest Inventory:
           First Empirical Results

    • First page: 4540
      Abstract: Data assimilation techniques were used to estimate forest stand data in 2011 by sequentially combining remote sensing based estimates of forest variables with predictions from growth models. Estimates of stand data, based on canopy height models obtained from image matching of digital aerial images at six different time-points between 2003 and 2011, served as input to the data assimilation. The assimilation routines were built on the extended Kalman filter. The study was conducted in hemi-boreal forest at the Remningstorp test site in southern Sweden (lat. 13°37′ N; long. 58°28′ E). The assimilation results were compared with two other methods used in practice for estimation of forest variables: the first was to use only the most recent estimate obtained from remotely sensed data (2011) and the second was to forecast the first estimate (2003) to the endpoint (2011). All three approaches were validated using nine 40 m radius validation plots, which were carefully measured in the field. The results showed that the data assimilation approach provided better results than the two alternative methods. Data assimilation of remote sensing time series has been used previously for calibrating forest ecosystem models, but, to our knowledge, this is the first study with real data where data assimilation has been used for estimating forest inventory data. The study constitutes a starting point for the development of a framework useful for sequentially utilizing all types of remote sensing data in order to provide precise and up-to-date estimates of forest stand parameters.
      PubDate: 2015-12-11
      DOI: 10.3390/f6124384
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4558-4572: Community Forestry Incentives and
           Challenges in Mozambique

    • Authors: Almeida Sitoe, Benard Guedes
      First page: 4558
      Abstract: Although communities have been living within forests and dependent on forest resources, in Mozambique, their role was not formally recognized until the late 1990s. The forest law of 1997 was the first to refer to communities as stakeholders in the forest sector, in line with the national Policy and Strategy for the Development of the Forestry and Wildlife Sector. As a new element, several pilot projects were established during the late 1990s and early 2000s to produce lessons that would inform policy and technical aspects. Community forestry received most of the attention until the first decade of this century, however, it seems that while communities have gained a role in the management of the forest sector, there are still challenges to fully implementing and securing community forestry initiatives. In this study, we document the advent and evolution of community forestry in Mozambique, discuss the conditions for success in community forestry, and discuss two cases of community forestry that have survived over beyond the end of external support. We conclude that devolution and training are the basic incentives, but additional incentives, including diversification of sources of revenue from non-destructive forestry activities, are required to maintain the stability of community forestry over time.
      PubDate: 2015-12-15
      DOI: 10.3390/f6124388
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4573-4587: The Influence of Stocking and Stand
           

    • First page: 4573
      Abstract: We analyzed productivity, in terms of periodic annual increment (PAI) in volume, of pure and mixed unmanaged naturally regenerated boreal stands mainly comprised of Populus tremuloides Michx. (trembling aspen) and Picea glauca (Moench) Voss (white spruce) ranging from 25–260 years old, in Alberta, Canada. Measures of density, site occupancy (Reineke’s stand density index-SDI), height, and site quality were evaluated in non-linear regression models aiming to explain the variation in PAI for the separate component species and for the entire stand. Analyses also included examination of the influence of stand composition. Results indicated a positive effect of both density of deciduous trees and of the percentage of deciduous tree stand basal area on trembling aspen volume PAI. White spruce PAI was positively influenced by spruce and aspen basal area, although effects of aspen were small. Height of both aspen and spruce were the most consistent independent variables in the models tested. Maximum PAI was achieved in mixed stands when site occupancy of both species was at its maximum, indicating the ecological combining ability of these two species. Variation in maximum stocking densities (i.e., stockability) has a strong influence on increment in these forests and is a major factor leading to increased productivity of mixed compared to pure stands.
      PubDate: 2015-12-15
      DOI: 10.3390/f6124387
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4588-4606: SLAM-Aided Stem Mapping for Forest
           Inventory with Small-Footprint Mobile LiDAR

    • First page: 4588
      Abstract: Accurately retrieving tree stem location distributions is a basic requirement for biomass estimation of forest inventory. Combining Inertial Measurement Units (IMU) with Global Navigation Satellite Systems (GNSS) is a commonly used positioning strategy in most Mobile Laser Scanning (MLS) systems for accurate forest mapping. Coupled with a tactical or consumer grade IMU, GNSS offers a satisfactory solution in open forest environments, for which positioning accuracy better than one decimeter can be achieved. However, for such MLS systems, positioning in a mature and dense forest is still a challenging task because of the loss of GNSS signals attenuated by thick canopy. Most often laser scanning sensors in MLS systems are used for mapping and modelling rather than positioning. In this paper, we investigate a Simultaneous Localization and Mapping (SLAM)-aided positioning solution with point clouds collected by a small-footprint LiDAR. Based on the field test data, we evaluate the potential of SLAM positioning and mapping in forest inventories. The results show that the positioning accuracy in the selected test field is improved by 38% compared to that of a traditional tactical grade IMU + GNSS positioning system in a mature forest environment and, as a result, we are able to produce a unambiguous tree distribution map.
      PubDate: 2015-12-17
      DOI: 10.3390/f6124390
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4607-4616: SE Asian Palms for Agroforestry and Home
           Gardens

    • Authors: Anders Barfod, Manju Balhara, John Dransfield, Henrik Balslev
      First page: 4607
      Abstract: Throughout SE Asia, palms are important in agroforestry systems and homegardens. Most species are used for multiple purposes based on both physical and nutritional properties of the palms. Except for a few commodities of worldwide importance such as palm oil and coconut, many palm products either do not figure in trade statistics, or they are merged with other products in a way, which makes it difficult to assess their importance. Here we focus on these products that are not prominent in national trade statistics and we review their sustainability and economic importance in SE Asia. We rank the most important palms according to their versatility, which is an extremely important property, especially for smallholders who practice subsistence agriculture. We conclude by listing a number of recommendations for future research directions based on experiences from the recently completed EU 7th Framework project (EU-PALMS 2009-2013).
      PubDate: 2015-12-17
      DOI: 10.3390/f6124389
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 4617-4633: Dynamics of Timber Market Integration in
           Sweden

    • Authors: Vishal Jaunky, Robert Lundmark
      First page: 4617
      Abstract: This paper addresses the performance of the timber markets (Scots pine, Pinus silvestris L. and Norway spruce, Picea abies (L.) Karst.) by evaluating the order of market integration in three Swedish regions (Central, Northern, and Southern). Quarterly data of delivery prices are employed over the period 1999Q1–2012Q4. Various unit root and cointegration tests have been computed. The results indicate that the variables are integrated of first order and co-integrated, especially after controlling for structural breaks. This supports the law-of-one-price hypothesis (LOP). However, the effects of structural shocks on forestry are arguably significant and these are controlled for while performing a vector error-correction mechanism (VECM)-based Granger-causality test. Bi-directional causality between the Northern and central markets is uncovered in the short-run. In the long-run, a similar causal effect is detected between Northern and Southern markets while the central market emerges as the price leader. Further investigation is carried out using variance decompositions and impulse response functions and these approaches also tend to confirm the existence of a single market well, as price interdependence between markets.
      PubDate: 2015-12-17
      DOI: 10.3390/f6124391
      Issue No: Vol. 6, No. 12 (2015)
       
  • Forests, Vol. 6, Pages 3809-3827: Intra-Annual Xylem Growth of Larix
           principis-rupprechtii at Its Upper and Lower Distribution Limits on the
           Luyashan Mountain in North-Central China

    • Authors: Yuan Jiang, Yiping Zhang, Yuanyuan Guo, Muyi Kang, Mingchang Wang, Biao Wang
      Pages: 3809 - 3827
      Abstract: Altitude-related climatic factors, especially temperature, are important factors that affect tree growth in mountain forest ecosystems. The aims of this study were to estimate the intra-annual radial growth differences of Larix principis-rupprechtii (L. principis-rupprechtii) between its upper and lower distribution limits, at 2740 and 2040 m a.s.l, respectively. Dynamics of xylem growth were observed by collecting microcore samples weekly during the 2011 growth season. The result indicated that different strategies were adopted at the two selected sites. Trees at the upper distribution limit adopted an “intensive strategy” with higher maximum growth rates (0.69 cell·day−1) within a shorter duration of 95 days, producing 21 new tracheids. By contrast, trees at the lower distribution limit exhibited an “extensive strategy” with lower maximum growth rates (0.53 cell·day−1) over a longer duration of 135 days, producing 50 tracheids. The soil temperature was probably the main factor limiting the onset of cambial activity for L. principis-rupprechtii, its daily mean thresholds for onset were 0 °C and 1.4 °C at the upper and lower distribution limits, respectively. These results indicate that L. principis-rupprechtii is able to adjust its xylem growth according to environmental conditions.
      PubDate: 2015-10-29
      DOI: 10.3390/f6113809
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3828-3846: A Bayesian Spatial Model Highlights
           Distinct Dynamics in Deforestation from Coca and Pastures in an Andean
           Biodiversity Hotspot

    • Pages: 3828 - 3846
      Abstract: The loss of tropical forests has continued in recent decades despite wide recognition of their importance to maintaining biodiversity. Here, we examine the conversion of forests to pastures and coca crops (illicit activity) on the San Lucas Mountain Range, Colombia for 2002–2007 and 2007–2010. Land use maps and biophysical variables were used as inputs to generate land use and cover change (LUCC) models using the DINAMICA EGO software. These analyses revealed a dramatic acceleration of the pace of deforestation in the region, with rates of conversion from forest to pasture doubling from the first to the second period. Altitude, distance to other crops, and distance to rivers were the primary drivers of deforestation. The influence of these drivers, however, differed markedly depending on whether coca cultivation or pastures replaced forest. Conversion to coca was more probable farther from other crops and from settlements. In contrast, proximity to other crops and to settlements increased conversion to pasture. These relationships highlight the different roles of coca and pastures in forest loss, with coca tending to open up new forest frontiers, and pastures tending to consolidate agricultural expansion and urban influence. Large differences between LUCC processes for each period suggest highly dynamic changes, likely associated with shifting underlying causes of deforestation. These changes may relate to shifts in demand for illicit crops, land, or mining products; however, the data to test these hypotheses are currently lacking. More frequent and detailed monitoring is required to guide actions to decrease the loss of forest in this highly vulnerable biodiversity hotspot in the Northern Andes.
      PubDate: 2015-10-30
      DOI: 10.3390/f6113828
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3847-3867: Does Tree Architectural Complexity
           Influence the Accuracy of Wood Volume Estimates of Single Young Trees by
           Terrestrial Laser Scanning?

    • Pages: 3847 - 3867
      Abstract: Accurate estimates of the wood volume or biomass of individual trees have gained considerable importance in recent years. The accuracy of wood volume estimation by terrestrial laser scanning (TLS) point cloud data may differ between individual trees due to species-specific differences in tree architecture. We selected three common and ecologically important central European deciduous tree species, which differ considerably in tree architectural complexity in early ontogenetic stages: Acer pseudoplatanus (simple), Sorbus aucuparia (intermediate) and Betula pendula (complex). We scanned six single young trees for each species (18 trees in total) under optimal scan conditions (single tree stand, leafless state, four scanning positions, high resolution). TLS-based volume estimates were derived for the total tree as well as for the two compartments; trunk and branches, using a voxel-based bounding box method. These estimates were compared with highly accurate xyolmetric (water displacement) volume measurements. Coefficients of determination between xylometric measurements and bounding box estimates were very high for total trees (R2adj = 0.99), trunks (R2adj = 0.99), and high for branches (R2adj = 0.78). The accuracy of estimations for total tree and trunk volume was highly similar among the three tree species. In contrast, significant differences were found for branch volume estimates: the accuracy was very high for Sorbus aucuparia, intermediate for Betula pendula, and low for Acer pseudoplatanus. A stepwise multiple regression showed that the accuracy of branch volume estimates was negatively related to the number of the first-order branches within diameter sizes of D ≤ 5 mm and crown surface area (R2adj = 0.61). We conclude that the accuracy in total tree and trunk volume estimates was not affected by the studied types of tree architectural complexity. The impact of the structural variability of branches and occlusion by branches was, thus, not as high as expected. In contrast, the accuracy of branch volume estimates was strongly influenced by tree architectural complexity, though not in a simple way. Because underestimations originated from different sources, the accuracy of branch volume estimates cannot be directly derived from the degree of architectural complexity. These results imply that the voxel-based bounding box method provides highly accurate total tree and trunk volume estimates, whereas further research is needed to improve branch volume estimation for young trees of different architectural types.
      PubDate: 2015-10-30
      DOI: 10.3390/f6113847
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3868-3881: Outbreak of Phoracantha semipunctata in
           Response to Severe Drought in a Mediterranean Eucalyptus Forest

    • Authors: Stephen Seaton, George Matusick, Katinka Ruthrof, Giles Hardy
      Pages: 3868 - 3881
      Abstract: Extreme climatic events, including droughts and heatwaves, can trigger outbreaks of woodboring beetles by compromising host defenses and creating habitat conducive for beetle development. As the frequency, intensity, and duration of droughts are likely to increase in the future, beetle outbreaks are expected to become more common. The combination of drought and beetle outbreaks has the potential to alter ecosystem structure, composition, and function. Our aim was to investigate a potential outbreak of the native Eucalyptus longhorned borer, Phoracantha semipunctata (P. semipunctata), following one of the most severe droughts on record in the Northern Jarrah Forest of Southwestern Australia. Beetle damage and tissue moisture were examined in trees ranging from healthy to recently killed. Additionally, beetle population levels were examined in adjacent forest areas exhibiting severe and minimal canopy dieback. Severely drought-affected forest was associated with an unprecedented outbreak of P. semipunctata, with densities 80 times higher than those observed in surrounding healthier forest. Trees recently killed by drought had significantly lower tissue moisture and higher feeding damage and infestation levels than those trees considered healthy or in the process of dying. These results confirm the outbreak potential of P. semipunctata in its native Mediterranean-climate Eucalyptus forest under severe water stress, and indicate that continued drying will increase the likelihood of outbreaks.
      PubDate: 2015-10-30
      DOI: 10.3390/f6113868
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3882-3898: Aboveground Biomass Estimation Using
           Structure from Motion Approach with Aerial Photographs in a Seasonal
           Tropical Forest

    • Authors: Tetsuji Ota, Miyuki Ogawa, Katsuto Shimizu, Tsuyoshi Kajisa, Nobuya Mizoue, Shigejiro Yoshida, Gen Takao, Yasumasa Hirata, Naoyuki Furuya, Takio Sano, Heng Sokh, Vuthy Ma, Eriko Ito, Jumpei Toriyama, Yukako Monda, Hideki Saito, Yoshiyuki Kiyono, Sophal Chann, Nang Ket
      Pages: 3882 - 3898
      Abstract: We investigated the capabilities of a canopy height model (CHM) derived from aerial photographs using the Structure from Motion (SfM) approach to estimate aboveground biomass (AGB) in a tropical forest. Aerial photographs and airborne Light Detection and Ranging (LiDAR) data were simultaneously acquired under leaf-on canopy conditions. A 3D point cloud was generated from aerial photographs using the SfM approach and converted to a digital surface model (DSMP). We also created a DSM from airborne LiDAR data (DSML). From each of DSMP and DSML, we constructed digital terrain models (DTM), which are DTMP and DTML, respectively. We created four CHMs, which were calculated from (1) DSMP and DTMP (CHMPP); (2) DSMP and DTML (CHMPL); (3) DSML and DTMP (CHMLP); and (4) DSML and DTML (CHMLL). Then, we estimated AGB using these CHMs. The model using CHMLL yielded the highest accuracy in four CHMs (R2 = 0.94) and was comparable to the model using CHMPL (R2 = 0.93). The model using CHMPP yielded the lowest accuracy (R2 = 0.79). In conclusion, AGB can be estimated from CHM derived from aerial photographs using the SfM approach in the tropics. However, to accurately estimate AGB, we need a more accurate DTM than the DTM derived from aerial photographs using the SfM approach.
      PubDate: 2015-10-30
      DOI: 10.3390/f6113882
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3899-3922: Characterizing the Height Structure and
           Composition of a Boreal Forest Using an Individual Tree Crown Approach
           Applied to Photogrammetric Point Clouds

    • Pages: 3899 - 3922
      Abstract: Photogrammetric point clouds (PPC) obtained by stereomatching of aerial photographs now have a resolution sufficient to discern individual trees. We have produced such PPCs of a boreal forest and delineated individual tree crowns using a segmentation algorithm applied to the canopy height model derived from the PPC and a lidar terrain model. The crowns were characterized in terms of height and species (spruce, fir, and deciduous). Species classification used the 3D shape of the single crowns and their reflectance properties. The same was performed on a lidar dataset. Results show that the quality of PPC data generally approaches that of airborne lidar. For pixel-based canopy height models, viewing geometry in aerial images, forest structure (dense vs. open canopies), and composition (deciduous vs. conifers) influenced the quality of the 3D reconstruction of PPCs relative to lidar. Nevertheless, when individual tree height distributions were analyzed, PPC-based results were very similar to those extracted from lidar. The random forest classification (RF) of individual trees performed better in the lidar case when only 3D metrics were used (83% accuracy for lidar, 79% for PPC). However, when 3D and intensity or multispectral data were used together, the accuracy of PPCs (89%) surpassed that of lidar (86%).
      PubDate: 2015-10-30
      DOI: 10.3390/f6113899
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3923-3945: Detecting Stems in Dense and Homogeneous
           Forest Using Single-Scan TLS

    • Authors: Shaobo Xia, Cheng Wang, Feifei Pan, Xiaohuan Xi, Hongcheng Zeng, He Liu
      Pages: 3923 - 3945
      Abstract: Stem characteristics of plants are of great importance to both ecology study and forest management. Terrestrial laser scanning (TLS) may provide an effective way to characterize the fine-scale structures of vegetation. However, clumping plants, dense foliage and thin structure could intensify the shadowing effect and pose a series of problems in identifying stems, distinguishing neighboring stems, and merging disconnected stem parts in point clouds. This paper presents a new method to automatically detect stems in dense and homogeneous forest using single-scan TLS data. Stem points are first identified with a two-scale classification method. Then a clustering approach is used to group the candidate stem points. Finally, a direction-growing algorithm based on a simple stem curve model is applied to merge stem points. Field experiments were carried out in two different bamboo plots with a stem density of about 7500 stems/ha. Overall accuracy of the stem detection is 88% and the quality of detected stems is mainly affected by the shadowing effect. Results indicate that the proposed method is feasible and effective in detection of bamboo stems using TLS data, and can be applied to other species of single-stem plants in dense forests.
      PubDate: 2015-10-30
      DOI: 10.3390/f6113923
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3946-3969: Participatory Multi-Criteria Assessment
           of Forest Planning Policies in Conflicting Situations: The Case of
           Tenerife

    • Authors: Montserrat Acosta, Serafin Corral
      Pages: 3946 - 3969
      Abstract: Sustainable forest planning should involve the participation of stakeholder communities in the decision-making process. This participation can help avoid the possible rejection of new planning measures. In this paper, the decision-making process to implement regulations on the use of forest tracks on the island of Tenerife (Canary Islands, Spain) is analyzed. In recent years, the number of people using the island’s forest environments has notably increased, leading to conflicts between different users of the tracks; as a result, the Island Council of Tenerife is working on regulating these pathways. This paper describes the framing analysis, design, and implementation of a participatory multi-criteria approach to explore, together with stakeholders, the best policy alternatives related to forest planning and management issues of forest track use. To do this, a set of tools has been developed, consisting of institutional analysis, participatory methods, and multi-criteria assessment techniques.
      PubDate: 2015-11-03
      DOI: 10.3390/f6113946
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3970-3984: Forest Biomass Energy Resources in
           China: Quantity and Distribution

    • Authors: Caixia Zhang, Leiming Zhang, Gaodi Xie
      Pages: 3970 - 3984
      Abstract: As one of the most important renewable and sustainable energy sources, the forest biomass energy resource has always been the focus of attention of scholars and policy makers. However, its potential is still uncertain in China, especially with respect to its spatial distribution. In this paper, the quantity and distribution of Chinese forest biomass energy resources are explored based mainly on forestry statistics data rather than forest resource inventory data used by most previous studies. The results show that the forest biomass energy resource in China was 169 million tons in 2010, of which wood felling and bucking residue (WFBR),wood processing residue (WPR), bamboo processing residue, fuel wood and firewood used by farmers accounted for 38%, 37%, 6%, 4% and 15%, respectively. The highest resource was located in East China, accounting for nearly 39.0% of the national amount, followed by the Southwest and South China regions, which accounted for 17.4% and 16.3%, respectively. At the provincial scale, Shandong has the highest distribution, accounting for 11.9% of total resources, followed by Guangxi and Fujian accounting for 10.3% and 10.2%, respectively. The actual wood-processing residue (AWPR) estimated from the actual production of different wood products (considering the wood transferred between regions) showed apparent differences from the local wood processing residue (LWPR), which assumes that no wood has been transferredbetween regions. Due to the large contribution of WPR to total forestry bioenergy resources, the estimation of AWPR will provide a more accurate evaluation of the total amount and the spatial distribution of forest biomass energy resources in China.
      PubDate: 2015-11-04
      DOI: 10.3390/f6113970
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3985-4000: Understanding the Factors Influencing
           Nonindustrial Private Forest Landowner Interest in Supplying Ecosystem
           Services in Cumberland Plateau, Tennessee

    • Authors: Nana Tian, Neelam Poudyal, Donald Hodges, Timothy Young, Kevin Hoyt
      Pages: 3985 - 4000
      Abstract: Private forests provide a range of ecosystem services for society including provisioning, regulating, cultural, and supporting services. Sustaining the supply of such services depends on the interest of nonindustrial private forest (NIPF) landowners in managing their forests for such services. Assessing factors that influence NIPF landowner intentions would be useful in identifying potential suppliers of ecosystem services and in designing and implementing outreach and education programs to elevate the interests of less interested landowners. Using data collected from a mail survey of NIPF landowners on the Cumberland Plateau of Tennessee, this study examined how landowner interest in supplying ecosystem services was influenced by socio-demographic characteristics, economic and market factors, land management objectives, and ownership motivations. To that end, a multivariate logistic regression model was employed to analyze the supply of three types of ecosystem services: carbon storage (regulating service), water quality (provisioning service), and aesthetics (cultural service). Results revealed that landowner interest in managing forests for ecosystem services were significantly related to socio-demographic factors, management and ownership characteristics, and availability of financial incentives. These findings will improve the understanding of the market segment of landowners as related to ecosystem services. The findings may facilitate the development of market protocols and outreach programs that promote payments for ecosystem services in Tennessee and elsewhere.
      PubDate: 2015-11-04
      DOI: 10.3390/f6113985
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4001-4033: Accounting for a Diverse Forest
           Ownership Structure in Projections of Forest Sustainability Indicators

    • Pages: 4001 - 4033
      Abstract: In this study, we assessed the effect of a diverse ownership structure with different management strategies within and between owner categories in long-term projections of economic, ecological and social forest sustainability indicators, representing important ecosystem services, for two contrasting Swedish municipalities. This was done by comparing two scenarios: one where the diversity of management strategies was accounted for (Diverse) and one where it was not (Simple). The Diverse scenario resulted in a 14% lower total harvested volume for the 100 year period compared to the Simple scenario, which resulted in a higher growing stock and a more favorable development of the ecological indicators. The higher proportion of sparse forests and the lower proportion of clear-felled sites made the Diverse scenario more appropriate for delivering access to common outdoor recreation activities, while the Simple scenario projected more job opportunities. Differences between the scenarios were considerable already in the medium term (after 20 years of simulation). Our results highlight the importance of accounting for the variety of management strategies employed by forest owners in medium- to long-term projections of the development of forest sustainability indicators.
      PubDate: 2015-11-06
      DOI: 10.3390/f6114001
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4034-4054: A Comparison of Airborne Laser Scanning
           and Image Point Cloud Derived Tree Size Class Distribution Models in
           Boreal Ontario

    • Authors: Margaret Penner, Murray Woods, Douglas Pitt
      Pages: 4034 - 4054
      Abstract: Airborne Laser Scanning (ALS) metrics have been used to develop area-based forest inventories; these metrics generally include estimates of stand-level, per hectare values and mean tree attributes. Tree-based ALS inventories contain desirable information on individual tree dimensions and how much they vary within a stand. Adding size class distribution information to area-based inventories helps to bridge the gap between area- and tree-based inventories. This study examines the potential of ALS and stereo-imagery point clouds to predict size class distributions in a boreal forest. With an accurate digital terrain model, both ALS and imagery point clouds can be used to estimate size class distributions with comparable accuracy. Nonparametric imputations were generally superior to parametric imputations; this may be related to the limitation of using a unimodal Weibull function on a relatively small prediction unit (e.g., 400 m2).
      PubDate: 2015-11-09
      DOI: 10.3390/f6114034
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4055-4058: Two-Year Survival of Gremmeniella
           abietina Conidia Collected on Branches Left on the Ground after Pine
           Harvesting

    • Authors: Gaston Laflamme, Danny Rioux
      Pages: 4055 - 4058
      Abstract: In 1972, it was reported that viable ascospores and conidia of Gremmeniella abietina, North American race, were present on dead branches up to 10 months after they were killed. In Sweden, the survival period of conidia of G. abietina, European race, was reported to be over 18 months. We investigated the viability of conidia produced by G. abietina, European race, over a 2-year period in eastern Canada. Infected branches with pycnidia were left on the ground in June 2006. Branches were sampled every month during three growing seasons. Conidia germination was tested monthly and showed a very high rate of germination (76%–98%) from July 2006 to August 2007. Very few pycnidia were detected in the fall of 2007 and in May 2008. In June and July 2008, no pycnidia could be observed, the shoots being in an advanced stage of decomposition. In light of these observations, it is recommended to delay pine plantation until after two growing seasons following harvesting of diseased pine trees.
      PubDate: 2015-11-09
      DOI: 10.3390/f6114055
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4059-4071: Forest Parameter Prediction Using an
           Image-Based Point Cloud: A Comparison of Semi-ITC with ABA

    • Authors: Johannes Rahlf, Johannes Breidenbach, Svein Solberg, Rasmus Astrup
      Pages: 4059 - 4071
      Abstract: Image-based point clouds obtained using aerial photogrammetry share many characteristics with point clouds obtained by airborne laser scanning (ALS). Two approaches have been used to predict forest parameters from ALS: the area-based approach (ABA) and the individual tree crown (ITC) approach. In this article, we apply the semi-ITC approach, a variety of the ITC approach, on an image-based point cloud to predict forest parameters and compare the performance to the ABA. Norwegian National Forest Inventory sample plots on a site in southeastern Norway were used as the reference data. Tree crown objects were delineated using a watershed segmentation algorithm, and explanatory variables were calculated for each tree crown segment. A multivariate kNN model for timber volume, stem density, basal area and quadratic mean diameter with the semi-ITC approach produced RMSEs of 30%, 46%, 25%, 26%, respectively. The corresponding measures for the ABA were 30%, 51%, 26%, 35%, respectively. Univariate kNN models resulted in timber volume RMSEs of 25% for the semi-ITC approach and 22% for the ABA. A non-linear logistic regression model with the ABA produced an RMSE of 23%. Both approaches predicted timber volume with comparable precision and accuracy at the plot level. The multivariate kNN model was slightly more precise with the semi-ITC approach, while biases were larger
      PubDate: 2015-11-10
      DOI: 10.3390/f6114059
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4072-4087: Genetic Variability and Phylogeny of
           European mountain ash ringspot-associated virus RNA3 and RNA4

    • Pages: 4072 - 4087
      Abstract: The European mountain ash ringspot-associated virus (EMARaV) is a multipartite RNA virus of negative polarity. It infects Sorbus aucuparia (common name—rowan) trees throughout their whole distribution area in North and Central Europe. It causes mottling, chlorotic ringspots and decline of the whole plant. Infected rowans are serious virus sources for rowans and other potential hosts. EMARaV incidence and population structure was investigated in Germany, Finland, Sweden, Scotland, and Norway. Overall, EMARaV variants from 42 rowan trees distributed in 20 different locations were studied with regard to the genetic variability of the p3- and p4-coding genome region, as well as the 5′ and 3′ untranslated regions (UTR) of RNA3. In six of the 42 analyzed samples we found much higher sequence diversities than previously reported at the amino acid level in RNA3 encoded p3 protein sequences as well as at the nucleotide level on the 5′ and 3′ UTR. The other 36 EMARaV variants confirmed the assumed conservation of the nucleocapsid protein coding region. In contrast, the p4-coding genome region showed a high conservation of both nucleotide and amino acid sequences. Both EMARaV proteins were under strong purifying selection pressure, probably acting to maintain the functional integrity of the p3 and p4 proteins.
      PubDate: 2015-11-11
      DOI: 10.3390/f6114072
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4088-4104: Characterization of Fungal Pathogens
           Associated with White Pine Needle Damage (WPND) in Northeastern North
           America

    • Authors: Kirk Broders, Isabel Munck, Stephen Wyka, Gloria Iriarte, Eric Beaudoin
      Pages: 4088 - 4104
      Abstract: Eastern white pine is a crucial ecological and economic component of forests in the northern USA and eastern Canada, and is now facing an emerging problem in white pine needle damage (WPND). It is still unclear whether WPND results from one, or the combination of several fungal pathogens. Therefore, the first objective of this study was to characterize the fungi associated with WPND in the northeastern United States and document the damage being done to mature eastern white pine as a result of repeated defoliation. To date, 22 species of fungi, either cultured from diseased pine needles or formed fruiting bodies on pine needles were identified based on morphology and sequence data. Lecanosticta acicola and a putative new species of Septorioides were the species most frequently recovered from diseased needles, in addition to needle cast fungi Lophophacidium dooksii and Bifusella linearis, two obligate fungal pathogens that were frequently observed on pine needles in the northeast, but have not been known to cause excessive defoliation of eastern white pine. A second objective was to monitor yearly the health of 63 pairs of healthy and unhealthy trees in eight affected locations throughout New England. Since 2012, affected trees are increasingly and repeatedly chlorotic and defoliated every year. Trees that were initially healthy are now exhibiting symptoms. While L. acicola appears to be the primary pathogen causing WPND, several other common needle pathogens are being more frequently observed and the role of climate change may be important in the disease ecology of WPND. These defoliation events, while once a sporadic occurrence, have now become more frequent as observed in continued crown deterioration of eastern white pine in long-term monitoring plots followed during the course of this three-year study.
      PubDate: 2015-11-12
      DOI: 10.3390/f6114088
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4105-4134: Monitoring Forest Recovery Following
           Wildfire and Harvest in Boreal Forests Using Satellite Imagery

    • Authors: Amar Madoui, Sylvie Gauthier, Alain Leduc, Yves Bergeron, Osvaldo Valeria
      Pages: 4105 - 4134
      Abstract: In the managed boreal forest, harvesting has become a disturbance as important as fire. To assess whether forest recovery following both types of disturbance is similar, we compared post-disturbance revegetation rates of forests in 22 fire events and 14 harvested agglomerations (harvested areas over 5–10 years in the same vicinity) in the western boreal forest of Quebec. Pre-disturbance conditions were first compared in terms of vegetation cover types and surficial deposit types using an ordination technique. Post-disturbance changes over 30 years in land cover types were characterized by vectors of succession in an ordination. Four post-disturbance stages were identified from the 48 land thematic classes in the Landsat images: “S0” stand initiation phase; “S1” early regeneration phase; “S2” stem exclusion phase; and “S3” the coniferous forest. Analyses suggest that fire occurs in both productive and unproductive forests, which is not the case for harvesting. Revegetation rates (i.e., rapidity with which forest cover is re-established) appeared to be more advanced in harvested agglomerations when compared with entire fire events. However, when considering only the productive forest fraction of each fire, the revegetation rates are comparable between the fire events and the harvested agglomerations. The S0 is practically absent from harvested agglomerations, which is not the case in the fire events. The difference in revegetation rates between the two disturbance types could therefore be attributed mostly to the fact that fire also occurs in unproductive forest, a factor that has to be taken into account in such comparisons.
      PubDate: 2015-11-18
      DOI: 10.3390/f6114105
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4135-4145: Designing Strategies for Epidemic
           Control in a Tree Nursery: the Case of Ash Dieback in the UK

    • Authors: Vasthi Chavez, Stephen Parnell, Frank Bosch
      Pages: 4135 - 4145
      Abstract: Ash dieback is a fungal disease (causal agent Hymenoscyphus fraxineus) infecting Common ash (Fraxinus excelsior) throughout temperate Europe. The disease was first discovered in the UK in 2012 in a nursery in Southern England, in plants which had been imported from the Netherlands. After sampling other recently planted sites across England, more infected trees were found. Tree trade from outside and across the UK may have facilitated the spread of invasive diseases which threaten the sustainability of forestry business, ecological niches and amenity landscapes. Detecting a disease in a nursery at an early stage and knowing how likely it is for the disease to have spread further in the plant trade network, can help control an epidemic. Here, we test two simple sampling rules that 1) inform monitoring strategies to detect a disease at an early stage, and 2) inform the decision of tracking forward the disease after its detection. We apply these expressions to the case of ash dieback in the UK and test them in different scenarios after disease introduction. Our results are useful to inform policy makers’ decisions on monitoring for the control and spread of tree diseases through the nursery trade.
      PubDate: 2015-11-18
      DOI: 10.3390/f6114135
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4146-4167: Towards Automated Characterization of
           Canopy Layering in Mixed Temperate Forests Using Airborne Laser Scanning

    • Authors: Reik Leiterer, Hossein Torabzadeh, Reinhard Furrer, Michael Schaepman, Felix Morsdorf
      Pages: 4146 - 4167
      Abstract: Canopy layers form essential structural components, affecting stand productivity and wildlife habitats. Airborne laser scanning (ALS) provides horizontal and vertical information on canopy structure simultaneously. Existing approaches to assess canopy layering often require prior information about stand characteristics or rely on pre-defined height thresholds. We developed a multi-scale method using ALS data with point densities >10 pts/m2 to determine the number and vertical extent of canopy layers (canopylayer, canopylength), seasonal variations in the topmost canopy layer (canopytype), as well as small-scale heterogeneities in the canopy (canopyheterogeneity). We first tested and developed the method on a small forest patch (800 ha) and afterwards tested transferability and robustness of the method on a larger patch (180,000 ha). We validated the approach using an extensive set of ground data, achieving overall accuracies >77% for canopytype and canopyheterogeneity, and >62% for canopylayer and canopylength. We conclude that our method provides a robust characterization of canopy layering supporting automated canopy structure monitoring.
      PubDate: 2015-11-18
      DOI: 10.3390/f6114146
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4168-4190: Quantifying the Effects of Biomass
           Market Conditions and Policy Incentives on Economically Feasible Sites to
           Establish Dedicated Energy Crops

    • Authors: Sandhya Nepal, Marco Contreras, George Stainback, John Lhotka
      Pages: 4168 - 4190
      Abstract: This study used a spatially-explicit model to identify the amount and spatial distribution of economically feasible sites for establishing dedicated energy crops under various market and policy scenarios. A sensitivity analysis was performed for a biomass market with different discount rates and biomass prices as well as policy scenarios including propriety tax exemption, carbon offset payments, and the inclusion of farmland for biomass production. The model was applied to a four-county study area in Kentucky representing conditions commonly found in the Ohio River Valley. Results showed that both biomass price and discount rate have a can strongly influence the amount of economically efficient sites. Rising the biomass price by 5 $·t−1 and lowering discount rate by 1% from the baseline scenario (40 $·t−1 and 5%) resulted in an over fourteen fold increment. Property tax exemption resulted in a fourfold increase, a carbon payment on only 1 $·t−1 caused a twelve fold increase and extending the landbase from marginal land to farmland only slightly increase the economically efficient sites. These results provide an objective evaluation of market and policy scenarios in terms of their potential to increase land availability for establishing dedicated energy crops and to promote the bioenergy industry.
      PubDate: 2015-11-18
      DOI: 10.3390/f6114168
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4191-4211: Phylogenetic Relationships among Species
           of Phellinus sensu stricto, Cause of White Trunk Rot of Hardwoods, from
           Northern North America

    • Authors: Nicholas Brazee
      Pages: 4191 - 4211
      Abstract: Species in Phellinus s.s. are some of the most important wood-decaying fungal pathogens in northern temperate forests, yet data on species incidence in North America remains limited. Therefore, phylogenetic analyses were performed using four loci (ITS, nLSU, tef1 and rpb2) with isolates representing 13 species. Results of phylogenetic analyses using maximum likelihood and Bayesian inference revealed that eight species of Phellinus s.s. occur in North America, and include: P. alni, P. arctostaphyli, P. betulinus, P. lundellii, P. nigricans, P. tremulae and two undescribed species, P. NA1 and P. NA2. Meanwhile, P. tuberculosus, P. igniarius s.s., P. populicola, P. laevigatus s.s. and P. orienticus were not detected and appear restricted to Europe and/or Asia. The tef1 dataset outperformed all other loci used and was able to discriminate among all 13 of the currently known Phellinus s.s. species with significant statistical support. The internal transcribed spacer (ITS) region performed well but a high level of intraspecific variation could lead to inflated taxa recognition. Phellinus alni exhibited the broadest host range, as demonstrated previously, and appears to be the most common species in northern hardwood (Acer-Betula-Fagus), northern floodplain (Fraxinus-Populus-Ulmus) and coastal alder (Alnus) forests of North America.
      PubDate: 2015-11-18
      DOI: 10.3390/f6114191
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4212-4227: Distributions and Losses of Logging
           Residues at Clear-Felled Areas during Extraction for Bioenergy: Comparing
           Dried- and Fresh-Stacked Method

    • Pages: 4212 - 4227
      Abstract: It is well known that a large proportion of available logging residues intended for extraction will not reach the energy-conversion industry, because some are lost during transportation or left on the clear-felled area. However, there is little understanding of where logging residue losses occur in the supply chain. In this study, the distribution of logging residues for two methods (dried- and fresh-stacked method) to extract logging residues were studied in one clear-felled area. In addition, residue fractions were examined in a detailed comparison. Even though the fresh-stacked method left somewhat more logging residues at the clear-felled area, the differences are small between the methods. Approximately 30% of the total amount of logging residues was left behind between the harvester heaps, with an additional 10%–15% under these heaps and approximately 2%–3% beneath the windrows. The final product that was delivered to the energy-conversion industry was very similar, regardless of the extraction method used. The delivered chipped logging residues had moisture contents of 37% and 36% following fresh- and dried-stacked methods respectively, and in both cases the needle content in the processed logging residues was approximately 10%. However, the total amount of fine fractions (needles and fines) was slightly higher following dried-stacking.
      PubDate: 2015-11-20
      DOI: 10.3390/f6114212
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4228-4244: Annual Cash Income from Community Forest
           Management in the Brazilian Amazon: Challenges for the Future

    • Authors: Marie-Gabrielle Piketty, Isabel Drigo, Philippe Sablayrolles, Evandro de Aquino, Driss Pena, Plinio Sist
      Pages: 4228 - 4244
      Abstract: Community forest management (CFM) is considered an alternative way to protect forests while providing income for smallholders. Since the mid-1990s, the number of CFM projects has rapidly increased in the Brazilian Amazon, although most of them still face several difficulties. In this paper, we discuss the obstacles to the financial viability of CFM in this region and propose some ways to overcome them. Based on evidence from five case studies, we assess the extent to which sustainable forest management for commercial timber production contributes to smallholder income. We show that harvesting timber only provides a limited cash income to smallholders, even though forest covers 80% of their landholding. Market access to timber is very uncertain and smallholder communities often fail to make a profit from their timber. Minimum remunerative public prices and support for timber marketing are thus needed. Simpler and more flexible procedures are required to reduce the high transaction costs of obtaining a permit and increase smallholder involvement in legal forest management for commercial purposes. Finally, a better assessment of timber potential in smallholder forest reserves through systematic inventories would be useful to avoid arousing false expectations.
      PubDate: 2015-11-20
      DOI: 10.3390/f6114228
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4245-4294: SimpleTree —An Efficient Open
           Source Tool to Build Tree Models from TLS Clouds

    • Authors: Jan Hackenberg, Heinrich Spiecker, Kim Calders, Mathias Disney, Pasi Raumonen
      Pages: 4245 - 4294
      Abstract: An open source tool named SimpleTree, capable of modelling highly accurate cylindrical tree models from terrestrial laser scan point clouds, is presented and evaluated. All important functionalities, accessible in the software via buttons and dialogues, are described including the explanation of all necessary input parameters. The method is validated utilizing 101 point clouds of six different tree species, in the main evergreen and coniferous trees. All scanned trees have been destructively harvested to get accurate estimates of above ground biomass with which we assess the accuracy of the SimpleTree-reconstructed cylinder models. The trees were grouped into four data sets and for each one a Concordance Correlation Coefficient of at least 0.92 (0.92, 0.97, 0.92, 0.94) and an total relative error at most  ~8 % (2.42%, 3.59%, –4.59%, 8.27%) was achieved in the comparison of the model results to the ground truth data. A global statistical improvement of derived cylinder radii is presented as well as an efficient optimization approach to automatically improve user given input parameters. An additional check of the SimpleTree results is presented via comparison to the results of trees reconstructed using an alternative, published method.
      PubDate: 2015-11-23
      DOI: 10.3390/f6114245
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4295-4327: Endurance and Adaptation of Community
           Forest Management in Quintana Roo, Mexico

    • Pages: 4295 - 4327
      Abstract: Despite regional deforestation threats, the state of Quintana Roo has maintained over 80% of its territory in forests. Community forest management (CFM) has played a pivotal role in forest cover and biodiversity conservation in the region. In this article, we present the institutional, socioeconomic and environmental conditions under which community-based forest management has been consolidated in the tropical state of Quintana Roo, which occupies the eastern half of Mexico’s Yucatan Peninsula. With a focus on management for timber and other market-based development strategies, we then examine the institutional and socioeconomic factors, as well as biophysical shocks, that have constrained community forestry development in the past 25 years, challenging its persistence. Following, we discuss how forest communities and institutions have responded and adapted to changing forest policies and markets as well as major environmental shocks from hurricanes and fires. CFM in Quintana Roo has shown resiliency since its institutionalization 30 years ago. Future challenges and opportunities include biodiversity conservation, carbon management through Reducing Emissions from Deforestation and Forest Degradation (REDD+) initiatives, market strengthening, business management training as well as the implementation of alternative silvicultural systems, particularly to manage sustainable populations of commercial timber species.
      PubDate: 2015-11-23
      DOI: 10.3390/f6114295
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4328-4348: Prescribing Innovation within a
           Large-Scale Restoration Programme in Degraded Subtropical Thicket in South
           Africa

    • Authors: Anthony Mills, Marius Vyver, Iain Gordon, Anand Patwardhan, Christo Marais, James Blignaut, Ayanda Sigwela, Barney Kgope
      Pages: 4328 - 4348
      Abstract: Commonly cited requirements for bridging the “science‑practice divide” between practitioners and scientists include: political support, communication and experimentation. The Subtropical Thicket Restoration Programme was established in 2004 to catalyse investment in large-scale restoration of degraded subtropical thicket in the Eastern Cape, South Africa. Political support has been strong, with the South African government investing more than US$8 million into the programme. Communication occurred regularly among a wide range of stakeholders, and a restoration experiment—comprising 12 treatments and ~300 plots—was established over an area of ~75,000 km2. Despite this support, communication and experimentation, many pitfalls were encountered. For example, one restoration protocol became entrenched in the programme’s public as well as private sector operations without continual scrutiny of its efficacy. This was largely because results from the large-scale restoration experiment only emerged a decade after its conceptualization. As the programme enters its second decade there is recognition that a full range of “intelligent tinkering”—from small, rapid experiments to large, long-term experiments—needs to be planned and prescribed. The new working hypothesis is that prescribed innovation will reduce costs of restoration, increase survivorship of plants, increase income streams from restored landscapes, and promote new financing mechanisms for restoration.
      PubDate: 2015-11-24
      DOI: 10.3390/f6114328
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4349-4359: Effects of Land Use on Flow Rate Change
           Indices

    • Pages: 4349 - 4359
      Abstract: The goal of this study was to analyze the impact of agriculture on the spatial and temporal variability of flow rate change indices from 1930 to 2008. The two indices used are the coefficient of immoderation (CI) and the coefficient of variation (CV). Values of these two indices are higher for the L’Assomption River agricultural watershed than for the Matawin River forested watershed due to higher runoff in the former than in the latter. The difference in these values between the two watersheds is greater for winter, but it is lower for summer, when the difference in runoff between the two watersheds is strongly attenuated by the presence of crops. Regarding the temporal variability, a difference between the two watersheds is observed in the fall. For the agricultural watershed, mean values of neither index show a break in slope, while a break is observed for the forested watershed. In both watersheds, both indices are positively correlated with maximum temperature and total rainfall in winter, but only to this latter climate variable in the fall. In springtime, the two indices are negatively correlated with minimum temperature in the forested watershed, but only CV is correlated, positively, with this same climate variable in the agricultural watershed.
      PubDate: 2015-11-24
      DOI: 10.3390/f6114349
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 4360-4373: Extent and Severity of Caliciopsis
           Canker in New England, USA: An Emerging Disease of Eastern White Pine
           (Pinus strobus L.)

    • Authors: Isabel Munck, William Livingston, Kyle Lombard, Thomas Luther, William Ostrofsky, Jennifer Weimer, Stephen Wyka, Kirk Broders
      Pages: 4360 - 4373
      Abstract: Caliciopsis canker is an emerging problem in Pinus growing regions of Eastern North America. The fungal disease caused by Caliciopsis pinea is associated with overstocked stands and poor sites, but few quantitative data are available. The objective of this study, therefore, was to assess the extent and severity of Caliciopsis canker and to explore environmental variables associated with disease to identify areas at risk of damage. During 2014, 58 sites across New England with >75% P. strobus basal area in public lands were surveyed. Most sites (72%) had Caliciopsis canker signs or symptoms. Caliciopsis pinea was successfully identified with molecular techniques. In sites with Caliciopsis canker, 36% of the mature pines were symptomatic. Pole sized and suppressed trees were more likely to be damaged than larger trees with dominant crown positions (p < 0.05). Pinus strobus density for sites with Caliciopsis canker was 311 trees/ha (mean P. strobus stand diameter = 40 cm) compared to 220 trees/ha (mean white pine stand diameter = 43 cm) for sites without Caliciopsis canker (p = 0.1). Caliciopsis canker symptoms tended to appear more frequently in stands with excessively drained, coarse textured soils derived from glacial outwash (86%) or stands with poorly drained soils and low fertility (78%) than in stands with well drained, more fertile soils (59%) (p = 0.1). The severity of symptoms varied among soil groups and was greater for excessively drained, nutrient poor soils than for well-drained, more fertile soils (p = 0.027).
      PubDate: 2015-11-24
      DOI: 10.3390/f6114360
      Issue No: Vol. 6, No. 11 (2015)
       
  • Forests, Vol. 6, Pages 3369-3394: Modeling Wood Fibre Length in Black
           Spruce (Picea mariana (Mill.) BSP) Based on Ecological Land Classification
           

    • Authors: Elisha Townshend, Bharat Pokharel, Art Groot, Doug Pitt, Jeffery Dech
      Pages: 3369 - 3394
      Abstract: Effective planning to optimize the forest value chain requires accurate and detailed information about the resource; however, estimates of the distribution of fibre properties on the landscape are largely unavailable prior to harvest. Our objective was to fit a model of the tree-level average fibre length related to ecosite classification and other forest inventory variables depicted at the landscape scale. A series of black spruce increment cores were collected at breast height from trees in nine different ecosite groups within the boreal forest of northeastern Ontario, and processed using standard techniques for maceration and fibre length measurement. Regression tree analysis and random forests were used to fit hierarchical classification models and find the most important predictor variables for the response variable area-weighted mean stem-level fibre length. Ecosite group was the best predictor in the regression tree. Longer mean fibre-length was associated with more productive ecosites that supported faster growth. The explanatory power of the model of fitted data was good; however, random forests simulations indicated poor generalizability. These results suggest the potential to develop localized models linking wood fibre length in black spruce to landscape-level attributes, and improve the sustainability of forest management by identifying ideal locations to harvest wood that has desirable fibre characteristics.
      PubDate: 2015-09-24
      DOI: 10.3390/f6103369
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3395-3411: Empirical Estimates of Aboveground
           Carbon in Open Eucalyptus Forests of South-Eastern Australia and Its
           Potential Implication for National Carbon Accounting

    • Authors: Liubov Volkova, Huiquan Bi, Simon Murphy, Christopher Weston
      Pages: 3395 - 3411
      Abstract: The aboveground carbon (AGC) storage of open Eucalyptus forests is unknown yet they are estimated to account for almost 25% of all Australian forests and about 60% of forests in Victoria. In this study we provide the best possible estimates of total AGC including tree biomass derived from destructive biomass sampling across 23 study plots established in open Eucalyptus forests in Victoria. The field estimates of AGC were then used for calibration of Australia’s National Carbon Accounting Model, FullCAM. The study aimed to develop a transparent and defendable method to estimate AGC for one of the most common Australian forests. Our calibrations showed that the 8.3 M ha of open Eucalyptus forests of SE Australia sequester at least 139 Mt C more than default FullCAM predictions. Because most of these forests are not subject to human-induced emission such as harvesting, only emissions and stock changes from a small area of these forests is reported in national inventories and international greenhouse emissions agreements. Concern for climate change and emission reduction will inevitably require land managers to come up with defendable methods of estimating forest carbon stocks and changes in all forest types; here we show how FullCAM can be further developed for this purpose.
      PubDate: 2015-09-24
      DOI: 10.3390/f6103395
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3412-3432: WIND-STORM: A Decision Support System
           for the Strategic Management of Windthrow Crises by the Forest Community

    • Pages: 3412 - 3432
      Abstract: Storms are one of the most damaging agents for European forests and can cause huge and long-term economic impacts on the forest sector. Recent events and research haves contributed to a better understanding and management of destructive storms, but public authorities still lack appropriate decision-support tools for evaluating their strategic decisions in the aftermath of a storm. This paper presents a decision support system (DSS) that compares changes in the dynamics of the regional forest-based sector after storm events under various crisis management options. First, the development and implementation of a regional forest model is addressed; then, the potential application of the model-based DSS WIND-STORM is illustrated. The results of simulated scenarios reveal that this DSS type is useful for designing a cost-effective regional strategy for storm-damage management in the context of scarce public resources and that public strategies must encompass the whole forest-based sector to be efficient. Additional benefits of such a DSS is to bring together decision-makers and forest stakeholders for a common objective and therefore to enhance participatory approaches to crisis management.
      PubDate: 2015-09-29
      DOI: 10.3390/f6103412
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3433-3451: An Uneven Playing Field: Regulatory
           Barriers to Communities Making a Living from the Timber from Their
           Forests–Examples from Cambodia, Nepal and Vietnam

    • Authors: David Gritten, Martin Greijmans, Sophie Lewis, Tol Sokchea, Julian Atkinson, Tan Quang, Bishnu Poudyal, Binod Chapagain, Lok Sapkota, Bernhard Mohns, Naya Paudel
      Pages: 3433 - 3451
      Abstract: Community forestry (CF) is widely viewed as the solution to many of the challenges facing forest management and governance in the Asia-Pacific region. However, it is often felt that CF is not delivering on its potential. This paper focuses on one possible limitation: the role of regulations in curbing communities’ ability to make a living from their timber resources. The work covers Cambodia, Nepal and Vietnam, using policy analyses, national level experts’ workshops, and focus group discussions in two CF sites in each country. The results highlight the fact that there are numerous, often prohibitive, regulations in place. One challenge is the regulations’ complexity, often requiring a level of capacity far beyond the ability of community members and local government staff. The paper puts forward various recommendations including simplifying regulations and making them more outcome-based, and facilitating key stakeholders, including government and community based organizations, working together on the design and piloting of forest monitoring based on mutually agreed forest management outcomes. The recommendations reflect the belief that for CF to succeed, communities must be allowed to make a meaningful living from their forests, a result of which would be increased investment in sustainable forest management.
      PubDate: 2015-09-29
      DOI: 10.3390/f6103433
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3452-3482: Legality Constraints: The Emergence of a
           Dual Market for Tropical Timber Products?

    • Authors: Mauro Masiero, Davide Pettenella, Paolo Cerutti
      Pages: 3452 - 3482
      Abstract: The European Union (EU), the United States of America (USA), and Australia have adopted specific measures to avoid the placing of illegal timber on their markets. These measures might encourage the diversion of timber products from traditional large importers to destinations with a less stringent regulatory framework. During 2001–2013, the international trade in tropical primary timber products (logs; sawnwood; veneers and plywood) decreased by 13% in volume and increased by almost 5% in value. Imports by Australia, the EU, and the USA halved, while those by emerging economies such as China and India initially remained stable and later increased. Tropical timber products—mostly logs and sawnwood—might have been diverted towards emerging economies over the period considered. This general trend is confirmed when analyzing imports from countries that are implementing voluntary partnership agreements (VPA) within the EU Forest Law Enforcement, Governance and Trade (FLEGT) Action Plan. Several factors might influence these market dynamics, including changes induced by the 2008 financial crisis and the increasing domestic demand for timber products by emerging nations. The effects of legality measures on market trends are still unclear. Nonetheless, they might have encouraged uncertainty with regards to traditional importers and favored emerging ones.
      PubDate: 2015-09-30
      DOI: 10.3390/f6103452
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3483-3500: Impact of a Mountain Pine Beetle
           Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    • Authors: Amalesh Dhar, Nicole Balliet, Kyle Runzer, Christopher Hawkins
      Pages: 3483 - 3500
      Abstract: The current mountain pine beetle (MPB) (Dendroctonous ponderosae Hopkins) epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age) trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in young pine stands and its possible impact on stand dynamics. Although MPB attacks were observed in trees as small as 7.5 cm diameter at breast height (DBH) and as young as 13 years old, the degree of MPB attack (percent stems ha−1) increased with increasing tree diameter and age class (13–20, 21–40, 41–60, and 61–80 years old) (6.4%, 49.4%, 62.6%, and 69.5% attack, respectively, by age class) which is greater than that reported from previous epidemics for stands of this age. The mean density of surviving residual structure varied widely among age classes and ecological subzones. Depending on age class, 65% to 77% of the attacked stands could contribute to mid-term timber supply. The surviving residual structure of young stands offers an opportunity to mitigate the effects of MPB-attack on future timber supply, increase age class diversity, and enhance ecological resilience in younger stands.
      PubDate: 2015-09-30
      DOI: 10.3390/f6103483
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3501-3513: Native and Alien Plant Species Richness
           Response to Soil Nitrogen and Phosphorus in Temperate Floodplain and Swamp
           Forests

    • Pages: 3501 - 3513
      Abstract: Soil nitrogen and phosphorus are commonly limiting elements affecting plant species richness in temperate zones. Our species richness-ecological study was performed in alder-dominated forests representing temperate floodplains (streamside alder forests of Alnion incanae alliance) and swamp forests (alder carrs of Alnion glutinosae alliance) in the Western Carpathians. Species richness (i.e., the number of vascular plants in a vegetation plot) was analyzed separately for native and alien vascular plants in 240 vegetation plots across the study area covering Slovakia, northern Hungary and southern Poland. The relationship between the species richness of each plant group and total soil nitrogen content, plant-available phosphorus and carbon to nitrogen (C/N) ratio was analyzed by generalized linear mixed models (GLMM) with Poisson error distribution and log-link function. The number of recorded native and alien species was 17–84 (average 45.4) and 0–9 (average 1.5) species per plot, respectively. The GLMMs were statistically significant (p ˂ 0.001) for both plant groups, but the total explained variation was higher for native (14%) than alien plants (9%). The richness of native species was negatively affected by the total soil nitrogen content and plant-available phosphorus, whereas the C/N ratio showed a positive impact. The alien richness was predicted only by the total soil nitrogen content showing a negative effect.
      PubDate: 2015-10-07
      DOI: 10.3390/f6103501
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3514-3527: Evaluating the Use of Tree Shelters for
           Direct Seeding of Castanea on a Surface Mine in Appalachia

    • Authors: Christopher Barton, Jarrod Miller, Kenton Sena, Patrick Angel, Michael French
      Pages: 3514 - 3527
      Abstract: American chestnut (Castanea dentata), once a primary constituent of the eastern hardwood forest ecosystem, was nearly extirpated from the forest canopy by the accidental introduction of chestnut blight (Cryphonectria parasitica). An intensive breeding program has sought to breed blight resistance from Chinese chestnut into American chestnuts, while maintaining as much of the desirable American chestnut phenotypes as possible. Previous studies suggest that these blight resistant American chestnuts, termed “restoration chestnuts”, are capable of thriving on reclaimed surface mines. We direct seeded pure Chinese, pure American, and three backcross lines into brown sandstone minesoil on a mine site in Pike County, KY. To investigate the effects of tree sheltering on survival and growth, we installed tree shelters on half the plots, and left the rest of the plots unsheltered. Results indicated that shelters were highly effective at reducing initial mortality. In addition, while pure Chinese chestnut survival was highest, the three backcross lines have also survived well on this site. Our study demonstrates that American, Chinese, and backcrossed chestnuts can survive through five growing seasons on reclaimed surface mines with the use of tree shelters.
      PubDate: 2015-10-07
      DOI: 10.3390/f6103514
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3528-3546: Carbon Budgets for Caribbean Mangrove
           Forests of Varying Structure and with Phosphorus Enrichment

    • Authors: Catherine Lovelock, Lorae Simpson, Lisa Duckett, Ilka Feller
      Pages: 3528 - 3546
      Abstract: There are few detailed carbon (C) budgets of mangrove forests, yet these are important for understanding C sequestration in mangrove forests, how they support the productivity of the coast and their vulnerability to environmental change. Here, we develop C budgets for mangroves on the islands of Twin Cays, Belize. We consider seaward fringing forests and interior scrub forests that have been fertilized with phosphorus (P), which severely limits growth of trees in the scrub forests. We found that respiration of the aboveground biomass accounted for 60%–80% of the fixed C and that respiration of the canopy and aboveground roots were important components of respiration. Soil respiration accounted for only 7%–11% of total gross primary production (GPP) while burial of C in soils was ~4% of GPP. Respiration by roots can account for the majority of soil respiration in fringing forests, while microbial processes may account 80% of respiration in scrub forests. Fertilization of scrub forests with P enhanced GPP but the proportion of C buried declined to ~2% of GPP. Net ecosystem production was 17%–27% of GPP similar to that reported for other mangrove forests. Carbon isotope signatures of adjacent seagrass suggest that dissolved C from mangroves is exported into the adjacent ecosystems. Our data indicate that C budgets can vary among mangrove forest types and with nutrient enrichment and that low productivity mangroves provide a disproportionate share of exported C.
      PubDate: 2015-10-07
      DOI: 10.3390/f6103528
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3547-3581: Loblolly Pine Growth Patterns on
           Reclaimed Mineland: Allometry, Biomass, and Volume

    • Authors: Jeremy Priest, Jeremy Stovall, Dean Coble, Brian Oswald, Hans Williams
      Pages: 3547 - 3581
      Abstract: Surface lignite coal mines in east Texas are commonly reforested using loblolly pine (Pinus taeda L.) following mining and reclamation activities. Due to the nature of such an extreme disturbance, altered growth patterns, growth rates, and productivity could be expected. We destructively sampled above- and belowground tissue to develop prediction equations specific to these sites. These prediction equations differed statistically from those found in the literature regarding unmined land. At the stand level, biomass and volume productivity appeared similar with young stands on reclaimed mineland performing slightly poorer than similarly managed unmined sites. Allometric partitioning of above- and belowground biomass differed statistically from the unmined allometric model previously studied. The allometric pattern on reclaimed mineland indicated greater partitioning of biomass belowground for young stands of low quadratic mean diameter relative to unmined stands. Older stands on reclaimed mineland exhibited no allometric partitioning differences from unmined stands, indicating the normal allometric pattern is resumed for stands greater than 10 years of age.
      PubDate: 2015-10-10
      DOI: 10.3390/f6103547
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3582-3593: Increased Biomass of Nursery-Grown
           Douglas-Fir Seedlings upon Inoculation with Diazotrophic Endophytic
           Consortia

    • Authors: Zareen Khan, Shyam Kandel, Daniela Ramos, Gregory Ettl, Soo-Hyung Kim, Sharon Doty
      Pages: 3582 - 3593
      Abstract: Douglas-fir (Pseudotsuga menziesii) seedlings are periodically challenged by biotic and abiotic stresses. The ability of endophytes to colonize the interior of plants could confer benefits to host plants that may play an important role in plant adaptation to environmental changes. In this greenhouse study, nursery-grown Douglas-fir seedlings were inoculated with diazotrophic endophytes previously isolated from poplar and willow trees and grown for fifteen months in nutrient-poor conditions. Inoculated seedlings had significant increases in biomass (48%), root length (13%) and shoot height (16%) compared to the control seedlings. Characterization of these endophytes for symbiotic traits in addition to nitrogen fixation revealed that they can also solubilize phosphate and produce siderophores. Colonization was observed through fluorescent microscopy in seedlings inoculated with gfp- and mkate-tagged strains. Inoculation with beneficial endophytes could prove to be valuable for increasing the production of planting stocks in forest nurseries.
      PubDate: 2015-10-12
      DOI: 10.3390/f6103582
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3594-3613: Estimating Values of Carbon
           Sequestration and Nutrient Recycling in Forests: An Application to the
           Stockholm-Mälar Region in Sweden

    • Authors: Ing-Marie Gren
      Pages: 3594 - 3613
      Abstract: We calculate values of forest carbon sequestration and nutrient recycling applying the replacement cost method. The value is then determined as the savings in costs by the replacement of more expensive abatement measures with these ecosystem services in cost-effective climate and nutrient programs. To this end, a dynamic optimization model is constructed, which accounts for uncertainty in sequestration. It is applied to the Stockholm-Mälar region in southeast Sweden where the EU 2050 climate policy for carbon emissions and the Baltic Sea action plan for nutrient discharges are applied. The results show that the value of carbon and nutrient sequestration can correspond to approximately 0.5% of the region’s gross domestic product, or 40% of the value of productive forest. The largest part of this value is attributed to carbon sequestration because of the relative stringency in targets and expensive alternative abatement measures. However, sequestration is uncertain because of stochastic weather conditions, and when society has a large risk aversion for not attaining climate and nutrient targets, the values of the forest carbon and nutrient sequestration can approach zero.
      PubDate: 2015-10-13
      DOI: 10.3390/f6103594
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3614-3664: Multiple-Use Zoning Model for Private
           Forest Owners in Agricultural Landscapes: A Case Study

    • Authors: Benoit Truax, Daniel Gagnon, France Lambert, Julien Fortier
      Pages: 3614 - 3664
      Abstract: Many small-scale private forest owners increasingly focus their management on amenity functions rather than on wood production functions. This paradigm shift is an opportunity to implement novel forestry management approaches, such as forested land zoning. Forest zoning consists in separating the land base in three zones that have different management objectives: (1) conservation zones; (2) ecosystem management zones; and (3) intensive production zones, which locally increase productivity, as a trade off to increase the land area dedicated to conservation and ecosystem management. We evaluate the ecological feasibility of implementing forest zoning on a private property (216 ha) at St-Benoît-du-Lac, Québec (Canada) characterised by agricultural and forest land uses. As a basis for delineating conservation and ecosystem management zones, historical and contemporary data and facts on forest composition and dynamics were reviewed, followed by a detailed forest vegetation analysis of forest communities. Delineating intensive production zones was straightforward, as fertile agricultural field margins located downslope were used to establish multifunctional hybrid poplar buffers. At St-Benoît-du-Lac, a realistic zoning scenario would consist of (1) conservation zones covering 25% of the forestland (37 ha); (2) ecosystem management zones covering 75% of the forestland (113 ha, including restoration zones on 24 ha); and (3) intensive production zones on 2.8 ha. Based on a yield projection of 13 t/ha/year for hybrid poplars, only 5.6% of agricultural field areas would need to be converted into agroforestry systems to allow for the loss of wood production in a conservation zone of 37 ha of forest. Ecosystem services provision following the implementation of zoning would include increased habitat quality, biodiversity protection and enhancement (by restoration of some tree species), carbon storage, non-point source aquatic pollution control, local biomass production for heating, and increased forest economic value.
      PubDate: 2015-10-14
      DOI: 10.3390/f6103614
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3665-3682: Biomass Stock and Carbon Sequestration
           in a Chronosequence of Pinus massoniana Plantations in the Upper Reaches
           of the Yangtze River

    • Authors: Meta Justine, Wanqin Yang, Fuzhong Wu, Bo Tan, Muhammad Khan, Yeyi Zhao
      Pages: 3665 - 3682
      Abstract: Planted forest plays a significant role in carbon sequestration and climate change mitigation; however, little information has been available on the distribution patterns of carbon pools with stand ages in Pinus massoniana Plantations. We investigated the biomass stock and carbon sequestration across a chronosequence (3-, 5-, 7-, 9-, 12-, 15-, 19-, 29-, 35- and 42-year) of stands with the main objectives: (1) to determine the biomass and carbon stock of the forest ecosystem; and (2) to identify factors influencing their distribution across the age series. Simple random sampling was used for collecting field data in the ten (10) stand ages. Three 20 × 20 m standard plots were laid out in February 2015 across the chronosequence. The diameter at breast height (DBH) and tree height (H) of each tree within each plot were measured using calipers and height indicator. Sub-plots of 2 × 2 m were established in each main plot for collecting soil samples at a 0–30- and 30–60-cm depth. Plantation biomass increased with increasing stand ages, ranging from 0.84 tonnes per hectare (t·ha−1) in the three-year stand to 252.35 t·ha−1 in the 42-year stand. The aboveground biomass (AGB) contributed 86.51%; the maximum value is 300-times the minimum value. Carbon concentrations and storage in mineral soil decreased with increasing soil depth, but were controlled by the management history of the ecosystem. The total ecosystem carbon storage varies with stand ages, ranging from 169.90 t·ha−1 in the five-year plantation to 326.46 t·ha−1 in the 42-year plantation, of which 80.29% comes from the mineral soil carbon and 19.71% from the vegetation. The ratio of the total carbon sequestration by the 42-year to the three-year stand was 1.70, implying substantial amounts of carbon accumulation during the transition period from young to mature-aged trees. The forest ecosystem had the capacity of storing up to 263.16 t·ha−1 carbon, assisting in mitigating climate change by sequestrating 965.83 t·ha−1 of CO2 equivalents, indicating that the forest is an important carbon sink.
      PubDate: 2015-10-15
      DOI: 10.3390/f6103665
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3683-3685: Michelotti, L. A. and Miesel J. R.
           Source Material and Concentration of Wildfire-Produced Pyrogenic Carbon
           Influence Post-Fire Soil Nutrient Dynamics. Forests 2015, 6,
           1325–1342

    • Authors: Lucas Michelotti, Jessica Miesel
      Pages: 3683 - 3685
      Abstract: The authors wish to make the following corrections to this paper [1]: [...]
      PubDate: 2015-10-15
      DOI: 10.3390/f6103683
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3686-3703: Influence of Rhizobia Inoculation on
           Biomass Gain and Tissue Nitrogen Content of Leucaena leucocephala
           Seedlings under Drought

    • Authors: Gabriela Pereyra, Henrik Hartmann, Beate Michalzik, Waldemar Ziegler, Susan Trumbore
      Pages: 3686 - 3703
      Abstract: Anticipated increases in the frequency of heat waves and drought spells may have negative effects on the ability of leguminous trees to fix nitrogen (N). In seedlings of Leucaena leucocephala inoculated with Mesorhizobium loti or Rhizobium tropici, we investigated how the developmental stage and a short drought influenced overall biomass and the accumulation of carbon and N in plant tissues. In early developmental stages, the number of nodules and nodule biomass were correlated with total plant biomass and δ15N, and nodules and roots contributed 33%–35% of the seedling total N. Seedlings associated with R. tropici fixed more N and exhibited higher overall biomass compared with M. loti seedlings. Four and a half months after inoculation (140 days after inoculation, DAI), a short (15-day) drought inhibited seedling growth and caused a decline in total plant N, with the smallest decline in R. tropici seedlings. After 15 days of drought, i.e., 155 DAI, the nodules had accumulated proline, but the total amino acid concentration did not change. Our results indicate that N-fixation is independent of seedlings growth. In addition, R. tropici is a better choice than M. loti as a symbiont for Leucaena seedlings for forest restoration and agroforestry applications under increasingly drier conditions.
      PubDate: 2015-10-15
      DOI: 10.3390/f6103686
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3704-3732: Comparing ALS and Image-Based Point
           Cloud Metrics and Modelled Forest Inventory Attributes in a Complex
           Coastal Forest Environment

    • Authors: Joanne White, Christoph Stepper, Piotr Tompalski, Nicholas Coops, Michael Wulder
      Pages: 3704 - 3732
      Abstract: Digital aerial photogrammetry (DAP) is emerging as an alternate data source to airborne laser scanning (ALS) data for three-dimensional characterization of forest structure. In this study we compare point cloud metrics and plot-level model estimates derived from ALS data and an image-based point cloud generated using semi-global matching (SGM) for a complex, coastal forest in western Canada. Plot-level estimates of Lorey’s mean height (H), basal area (G), and gross volume (V) were modelled using an area-based approach. Metrics and model outcomes were evaluated across a series of strata defined by slope and canopy cover, as well as by image acquisition date. We found statistically significant differences between ALS and SGM metrics for all strata for five of the eight metrics we used for model development. We also found that the similarity between metrics from the two data sources generally increased with increasing canopy cover, particularly for upper canopy metrics, whereas trends across slope classes were less consistent. Model outcomes from ALS and SGM were comparable. We found the greatest difference in model outcomes was for H (ΔRMSE% = 5.04%). By comparison, ΔRMSE% was 2.33% for G and 3.63% for V. We did not discern any corresponding trends in model outcomes across slope and canopy cover strata, or associated with different image acquisition dates.
      PubDate: 2015-10-15
      DOI: 10.3390/f6103704
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3733-3747: Trade-Offs between Drought Survival and
           Rooting Strategy of Two South American Mediterranean Tree Species:
           Implications for Dryland Forests Restoration

    • Authors: Juan Ovalle, Eduardo Arellano, Rosanna Ginocchio
      Pages: 3733 - 3747
      Abstract: Differences in water-acquisition strategies of tree root systems can determine the capacity to survive under severe drought. We evaluate the effects of field water shortage on early survival, growth and root morphological variables of two South American Mediterranean tree species with different rooting strategies during two growing seasons. One year-old Quillaja saponaria (deep-rooted) and Cryptocarya alba (shallow-rooted) seedlings were established under two watering treatments (2 L·week−1·plant−1 and no water) in a complete randomized design. Watering improved the final survival of both species, but the increase was only significantly higher for the shallow-rooted species. The survival rates of deep- and shallow-rooted species was 100% and 71% with watering treatment, and 96% and 10% for the unwatered treatment, respectively. Root morphological variables of deep-rooted species such as surface area, volume, and diameter were higher under unwatered treatment. On the other hand, shallow-rooted species had a higher total root dry mass, length, surface area with watering treatments. Our findings suggest that deep-rooted species are highly recommended for reforestation in dry conditions, even under low soil water availability. Water supplements during the summer season can attenuate the differences between deep- and shallow-rooted species in their ability to survive drought during the early stage.
      PubDate: 2015-10-15
      DOI: 10.3390/f6103733
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3748-3762: Using Plant Temperature to Evaluate the
           Response of Stomatal Conductance to Soil Moisture Deficit

    • Authors: Ming-Han Yu, Guo-Dong Ding, Guang-Lei Gao, Yuan-Yuan Zhao, Lei Yan, Ke Sai
      Pages: 3748 - 3762
      Abstract: Plant temperature is an indicator of stomatal conductance, which reflects soil moisture stresses. We explored the relationship between plant temperature and soil moisture to optimize irrigation schedules in a water-stress experiment using Firmiana platanifolia (L. f.) Marsili in an incubator. Canopy temperature, leaf temperature, and stomatal conductance were measured using thermal imaging and a porometer. The results indicated that (1) stomatal conductance decreased with declines in soil moisture, and reflected average canopy temperature; (2) the variation of the leaf temperature distribution was a reliable indicator of soil moisture stress, and the temperature distribution in severely water-stressed leaves exhibited greater spatial variation than that in the presence of sufficient irrigation; (3) thermal indices (Ig) and crop water stress index (CWSI) were theoretically proportional to stomatal conductance (gs), Ig was certified to have linearity relationship with gs and CWSI have a logarithmic relationship with gs, and both of the two indices can be used to estimate soil moisture; and (4) thermal imaging data can reflect water status irrespective of long-term water scarcity or lack of sudden rainfall. This study applied thermal imaging methods to monitor plants and develop adaptable irrigation scheduling, which are important for the formulation of effective and economical agriculture and forestry policy.
      PubDate: 2015-10-16
      DOI: 10.3390/f6103748
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3763-3778: Maturation in Corymbia torelliana ×
           C. citriodora Stock Plants: Effects of Pruning Height on Shoot Production,
           Adventitious Rooting Capacity, Stem Anatomy, and Auxin and Abscisic Acid
           Concentrations

    • Authors: Ivar Wendling, Paul Warburton, Stephen Trueman
      Pages: 3763 - 3778
      Abstract: Repeated pruning of stock plants is a common approach to delaying maturation and maintaining the propagation ability of cuttings, but little is known about the hormonal or anatomical basis for this phenomenon. We tested the effect of two different stock-plant pruning heights (15 cm and 30 cm) on shoot production, rooting capacity and rooted cutting vigour of six clones of the eucalypt Corymbia torelliana × C. citriodora. We determined whether differences in rooting potential were related to indole-3-acetic (IAA) and abscisic acid (ABA) concentrations, or the degree of lignification or sclerification, of the cuttings. Maintaining stock plants at 15 cm height sometimes reduced the production of stem cuttings. However, it often increased the ensuing percentage of cuttings that formed roots, with mean rooting across all clones increasing from 30%–53%. Therefore, the number of rooted cuttings produced by short stock plants was similar to, or higher than, the number produced by tall stock plants. Cuttings from shorter stock plants had faster root elongation and occasionally greater root dry mass, shoot dry mass or shoot height than cuttings from tall stock plants. These differences in rooting potential were generally not related to differences in IAA or ABA concentrations of the cuttings or to differences in their stem anatomy. Pruning at the lower height was more effective in maintaining clonal juvenility, supporting previous findings that stock plant maturation is a limiting factor in clonal propagation of Corymbia torelliana × C. citriodora.
      PubDate: 2015-10-16
      DOI: 10.3390/f6103763
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3779-3798: Effects of Visual Grading on Northern
           Red Oak (Quercus rubra L.) Seedlings Planted in Two Shelterwood Stands on
           the Cumberland Plateau of Tennessee, USA

    • Authors: Stacy Clark, Scott Schlarbaum, Callie Schweitzer
      Pages: 3779 - 3798
      Abstract: Artificial regeneration of oak has been generally unsuccessful in maintaining the oak component in productive upland forests of eastern North America. We tested visual grading effects on quality-grown northern red oak (Quercus rubra) seedlings planted in two submesic stands on the Cumberland Plateau escarpment of Tennessee, USA. Seedlings were grown for one year using advanced fertilization and irrigation protocols to increase overall size of seedlings, but large variability in size was still evident. Seedlings were divided into two grades prior to planting. The “standard” grade represented seedlings that had undergone a light culling, and the “premium” grade represented the highest quality seedlings. Seven years after planting in a midstory-removal stand, 50 percent of trees survived, growth was negligible, and seedling grade had no effect on survival and yearly growth. In a shelterwood harvest stand, premium grade seedlings had taller height and larger basal diameter (BD) (241 cm and 29.5 mm, respectively) compared to standard seedlings (201 cm and 25.9 mm, respectively), and a two-year height growth advantage was achieved by planting premium grade compared to standard grade seedlings. Competitive ability and planting shock were similar between grades, and we postulate that an exceptional drought and large size variability in both grades equalized response. While our findings should be confirmed through additional testing, they suggest currently accepted seedling quality standards for northern red oak should be refined to improve regeneration efforts on productive sites in the eastern United States.
      PubDate: 2015-10-21
      DOI: 10.3390/f6103779
      Issue No: Vol. 6, No. 10 (2015)
       
  • Forests, Vol. 6, Pages 3799-3808: Assessing 62 Chinese Fir (Cunninghamia
           lanceolata) Breeding Parents in a 12-Year Grafted Clone Test

    • Authors: Huiquan Zheng, Dehuo Hu, Runhui Wang, Ruping Wei, Shu Yan
      Pages: 3799 - 3808
      Abstract: Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is one of the major commercial conifer species in China. The present study concentrated on the assessment of growth, wood property traits, and strobili number in a 12-year grafted clone test of 62 Chinese fir breeding parents, aiming to describe the variation and correlations between these traits and to identify parent clones with the highest potential for future breeding. The results indicate that all of the growth (height, diameter at breast height, stem volume, crown-width) and wood property (wood basic density and hygroscopicity) traits varied significantly (p < 0.01) among clones, with coefficients of variation ranging from 7.6% to 30.6%. Furthermore, these traits consistently had a moderate to high (0.39–0.87) repeatability estimate (broad-sense heritability). Remarkable clonal differences were also observed for the production of male and female strobili. Phenotypic correlations among growth traits were strong (p < 0.01) and positive. Significantly negative correlations (p < 0.01 or 0.05) were found between wood basic density and growth (except for height) and hygroscopicity. The production of male and female strobili appeared to be significantly (p < 0.01) positively correlated with each other. A notable number of faster-growing parent clones were identified (n = 30); 11 of these had higher density wood with an average realized gain of 10.5% in diameter, and a 5.4% gain in wood basic density. When selection was made for growth and strobili, 10 faster-growing parent clones with medium to high production of female strobili were identified.
      PubDate: 2015-10-22
      DOI: 10.3390/f6103799
      Issue No: Vol. 6, No. 10 (2015)
       
 
 
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