Open AccessArticle
Management Goals and Performance: Clustering State Forest Management Organizations in Europe with Multivariate Statistics
Forests 2017, 8(12), 504; doi:10.3390/f8120504 (registering DOI) -
Abstract
State Forest Management Organizations (SFMOs) play a crucial role in the European forest sector, managing almost half of the forests in the region. SFMOs are often only managed for timber production, whereas, being publicly owned, they should play an important role in providing
[...] Read more.
State Forest Management Organizations (SFMOs) play a crucial role in the European forest sector, managing almost half of the forests in the region. SFMOs are often only managed for timber production, whereas, being publicly owned, they should play an important role in providing a vast range of public goods (e.g., soil protection, biodiversity conservation). Their management goals depend on the history and current conditions of the forest sector at a national level, as well as different challenges and the potential for development. Although there is a lack of knowledge about the current performance of SFMOs, there have been recent changes to their management goals and practices in response to the new demands expressed by society (e.g., transparency, social inclusion). The main purpose of this study was to analyze the current situation of SFMOs by grouping them with the help of a Cluster Analysis according to indicators that reflect the three pillars of the common understanding of the sustainable forest management (SFM) concept. Additionally, in light of the differences in the forest practices and management priorities in each country, we used Principal Component Analysis (PCA) to group countries according to common characteristics of the forest sector at the national level. The results showed three main clusters of SFMOs in Europe. The first cluster had a rather small but commercially-oriented forestry unit together with other business activities and a strong focus on public services. The second focused on public interest, rather than commercially-oriented organizations. The third is mainly profit-seeking. The existence of diverse SFMO clusters shows the possibility of different approaches for SFM with a focus on different goals (e.g., profit gaining, public service delivery). Full article
Figures

Figure 1

Open AccessArticle
Assessing Ecosystem Services in Rubber Dominated Landscapes in South-East Asia—A Challenge for Biophysical Modeling and Transdisciplinary Valuation
Forests 2017, 8(12), 505; doi:10.3390/f8120505 (registering DOI) -
Abstract
The concept of ecosystem services (ESS) has been increasingly recognized for its potential in decision making processes concerning environmental policy. Multidisciplinary projects on rubber (Hevea brasiliensis) cultivation, integrating research on a variety of ESS, have been few and far between. More
[...] Read more.
The concept of ecosystem services (ESS) has been increasingly recognized for its potential in decision making processes concerning environmental policy. Multidisciplinary projects on rubber (Hevea brasiliensis) cultivation, integrating research on a variety of ESS, have been few and far between. More than three years of iterative workshops with regional stakeholders resulted in the development of future land use scenarios for our study area in Xishuangbanna, PR China. We used the InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) modeling framework to analyze their impact on sediment retention, water yield, habitat quality, and carbon sequestration and developed a model for assessing rubber yields. We investigated the percentage deviations of integrated ESS indices in each scenario, as compared to the initial state of 2015 and as a novelty used different statistical weighting methods to include rankings for the preference of ESS from three contrasting stakeholder groups. The business-as-usual scenario (BAU, continuous rubber expansions) revealed an increase in rubber yields trading off against all other ESS analyzed. Compared to BAU, the measures introduced in the balanced-trade-offs scenario (reforestation, reduced herbicide application, riverine buffer zones, etc.) reduced the total amount of rubber yield but enhanced habitat quality and regulating ESS. The results show that the integrated indices for the provisioning of ESS would be overestimated without the inclusion of the stakeholder groups. We conclude that policy regulations, if properly assessed with spatial models and integrated stakeholder feedback, have the potential to buffer the typical trade-off between agricultural intensification and environmental protection. Full article
Figures

Figure 1

Open AccessArticle
Community Earth System Model Simulations Reveal the Relative Importance of Afforestation and Forest Management to Surface Temperature in Eastern North America
Forests 2017, 8(12), 499; doi:10.3390/f8120499 -
Abstract
Afforestation changes the land surface energy balance, though the effects on climate in temperate regions is uncertain, particularly the changes associated with forest management. In this study, we used idealized Community Earth System Model simulations to assess the influence of afforestation and afforestation
[...] Read more.
Afforestation changes the land surface energy balance, though the effects on climate in temperate regions is uncertain, particularly the changes associated with forest management. In this study, we used idealized Community Earth System Model simulations to assess the influence of afforestation and afforestation management in eastern North America on climate via changes in the biophysics of the land surface. Afforestation using broadleaf deciduous trees maintained at high leaf area index (LAI) in the southern part of the study region provided the greatest climate benefit by cooling summer surface air temperatures (Tsa). In contrast, the greatest warming occurred in the northern extent of the study region when afforesting with needleleaf evergreen trees maintained at high LAI. Forest management had an equal or greater influence on Tsa than the overall decision to afforest land in the southern extent of the region. Afforestation had a greater influence on Tsa than forest management in the northern extent. Integrating our results, focused on biophysical processes, with other research quantifying carbon cycle sensitivity to management can help guide the use of temperate afforestation to optimize climate benefits. Further, our results highlight the potential importance of including forest management in simulations of past and future climate. Full article
Figures

Figure 1

Open AccessArticle
Certifying Forests to Achieve Sustainability in Industrial Plantations: Opinions of Stakeholders in Spain
Forests 2017, 8(12), 502; doi:10.3390/f8120502 -
Abstract
Forest certification is a practice that has been consolidated worldwide in recent years as a result of certification often being associated with sustainability. However, there is not much research available on the perception of stakeholders and experts of that association. This study evaluates
[...] Read more.
Forest certification is a practice that has been consolidated worldwide in recent years as a result of certification often being associated with sustainability. However, there is not much research available on the perception of stakeholders and experts of that association. This study evaluates how key stakeholders relate certification to sustainability, and its implications for forest management. A survey was implemented in the eucalyptus plantations of Galicia, northwestern Spain, to assess how forest managers; advisors; environmental organizations; researchers; and members from the FSC (Forest Stewardship Council), PEFC (the Program for Endorsement of Forest Certification), and forest companies and associations, perceive this relationship. The opinions indicate that it should not be assumed that certified plantations are necessarily perceived as the most sustainable ones, that there is always a direct relationship between certification, nor that forest owners and managers certify their woodlands in order to guarantee sustainability. The results also showed that perceptions of certification and sustainability were not influenced by the opinions of different groups of stakeholders. Full article
Figures

Figure 1

Open AccessArticle
Effects of Climate Change on the Climatic Niches of Warm-Adapted Evergreen Plants: Expansion or Contraction?
Forests 2017, 8(12), 500; doi:10.3390/f8120500 -
Abstract
Climate change has modified the structure and functions of ecosystems, affecting human well-being. Evergreen plants in the warm-temperate ecosystems will lose climatically suitable habitats under climate change but have not drawn much scholarly interest. Therefore, the present research aimed to predict the future
[...] Read more.
Climate change has modified the structure and functions of ecosystems, affecting human well-being. Evergreen plants in the warm-temperate ecosystems will lose climatically suitable habitats under climate change but have not drawn much scholarly interest. Therefore, the present research aimed to predict the future climatic niches of eight coastal warm-adapted evergreen trees under climate change to provide information for an effective management practice. For this purpose, we used the ensemble species distribution models (SDMs) weighted by the TSS value in modelling the climatic niches of those evergreen trees and then ensembled their future distributions predicted under 20 future climate scenarios. Except for Neolitsea sericea (True Skill Statistic (TSS) = 0.79), all projections for the current climatic niches of evergreens showed excellent predictive powers (TSS > 0.85). The results showed that the climatic niches of the four evergreens—Castanopsis cuspidata, Pittosporum tobira, Raphiolepis indica var. umbellate, and Eurya emarginata—would expand to the northern part of the Korean Peninsula (KP) under climate change, but the ones of the remaining four—Kadsura japonica, Neolitsea sericea, Ilex integra, and Dendropanax morbiferus—would shrink. While the climatic niches of Pittosporum tobira showed the rapidest and greatest expansion under climate change, Dendropanax morbiferus was predicted to experience the greatest loss of habitat. On the other hand, regardless of whether the future distributions of climatically suitable habitats would expand or contract, the highly suitable habitats of all species were predicted to decline under climate change. This may indicate that further climate change will degrade habitat suitability for all species within the distribution boundary and restrict continuous habitat expansions of expanding species or accelerate habitat loss of shrinking species. In addition, the future distributions of most coastal evergreens were found to be confined to coastal areas; therefore, sea-level rise would accelerate their habitat loss under climate change. The present study provides primary and practical knowledge for understanding climate-related coastal vegetation changes for future conservation planning, particularly on the Korean Peninsula. Full article
Figures

Figure 1

Open AccessArticle
Combined Analysis of mRNAs and miRNAs to Identify Genes Related to Biological Characteristics of Autotetraploid Paulownia
Forests 2017, 8(12), 501; doi:10.3390/f8120501 -
Abstract
Autopolyploid plants and their organs are larger than their corresponding diploid ancestors, and they attract considerable attention for plant breeding. Paulownia is a fast-growing tree. To identify genes related to the biological characteristics of tetraploid Paulownia, transcriptome and small RNA sequencing were used
[...] Read more.
Autopolyploid plants and their organs are larger than their corresponding diploid ancestors, and they attract considerable attention for plant breeding. Paulownia is a fast-growing tree. To identify genes related to the biological characteristics of tetraploid Paulownia, transcriptome and small RNA sequencing were used to identify the key gene expression regulation in tetraploid Paulownia fortunei and tetraploid P. tomentosa and their corresponding diploids. A total of 1977 common differentially expressed genes (DEGs) and 89 differentially expressed miRNAs (DEMs) (38 conserved and 51 novel) were obtained in tetraploid vs. diploid comparisons of the two Paulownia species, and 18 target genes were identified by target prediction. Finally, by analyzing the expression profiles of the DEGs and DEMs and their target genes, we discovered that Pau-miR169, Pau-miR408 and Pau-miR156 interacted with their target gene nuclear transcription factor Y subunit A-9 (NF-YA9), serine/threonine protein phosphatase (PP1) and s-adenosyl-methionine-sterol-c-methyltransfera—se (SAM:SMT) to regulate the abiotic stress tolerance and the timber quality of the tetraploid Paulownia. This study lays a molecular biology foundation for understanding autotetraploid Paulownia and will benefit future breeding work. Full article
Figures

Figure 1

Open AccessArticle
Mortality and Recovery of Hemlock Woolly Adelgid (Adelges tsugae) in Response to Winter Temperatures and Predictions for the Future
Forests 2017, 8(12), 497; doi:10.3390/f8120497 -
Abstract
Eastern (Tsuga canadensis) and Carolina hemlocks (T. caroliniana) of eastern North America have been attacked by the non-native hemlock woolly adelgid (Adelges tsugae Annand) (HWA) since the first half of the 20th century. Unlike most insects, HWA develops
[...] Read more.
Eastern (Tsuga canadensis) and Carolina hemlocks (T. caroliniana) of eastern North America have been attacked by the non-native hemlock woolly adelgid (Adelges tsugae Annand) (HWA) since the first half of the 20th century. Unlike most insects, HWA develops through one generation from fall to late winter, exposing this insect to the lethal effects of winter temperatures. The mortality inflicted by winter temperatures on HWA determines the surviving population density as well as its ability to spread to uninfested areas. With the ongoing changes in climate, knowledge of this species’ ability to survive and spread in the future can help land managers prepare for its management. This study began during the winter of 2014 and ended in the spring of 2017. During this period, winter mortality of HWA was recorded at 100 sites from Maine to Georgia (n = 209). Changes in population density from the sistens to the succeeding progrediens generation were recorded at 24 sites (n = 35). Models were developed to predict HWA mortality using the lowest minimum temperature prior to the mortality assessment date, the number of days with mean temperature <−1 °C, and the mean daily temperature of the three days preceding that minimum. Models were also developed to predict population density changes from the overwintering sistens generation to the following progrediens generation. Future projections under climate change showed increases in winter survival and population growth rates over time. Especially towards the northeastern edge of T. canadensis’ distribution as minimum temperatures are predicted to increase at a greater rate. This will result in an increase in density throughout its current distribution and expansion northward causing an increase in its impact on eastern Tsuga spp. Full article
Figures

Figure 1

Open AccessReview
The Contribution of Traditional Ecological Knowledge and Practices to Forest Management: The Case of Northeast Asia
Forests 2017, 8(12), 496; doi:10.3390/f8120496 -
Abstract
This study aims to introduce the potential applicability of traditional ecological knowledge and community forestry in Northeast Asia, including China, Japan, and South Korea. In ancient Northeast Asia, forest policies and practices were based on Fengshui (an old Chinese concept regarding the flow
[...] Read more.
This study aims to introduce the potential applicability of traditional ecological knowledge and community forestry in Northeast Asia, including China, Japan, and South Korea. In ancient Northeast Asia, forest policies and practices were based on Fengshui (an old Chinese concept regarding the flow of vital forces), with which forests were managed under community forestry. However, these traditional systems diminished in the twentieth century owing to the decline of traditional livelihood systems and extreme deforestation. Recently, legacies from traditional ecological knowledge and community forestry have been revisited and incorporated into forest policies, laws, and management practices because of growing needs for sustainable forest use in China, Japan, and Korea. This reevaluation of traditional ecological knowledge and community forestry has provided empirical data to help improve forestry systems. Although traditional ecological knowledge and community forestry in Northeast Asia have been scarcely theorized, they play a significant role in modifying forest management practices in the face of socioeconomic changes. Full article
Figures

Figure 1

Open AccessArticle
Modeling and Predicting Carbon and Water Fluxes Using Data-Driven Techniques in a Forest Ecosystem
Forests 2017, 8(12), 498; doi:10.3390/f8120498 -
Abstract
Accurate estimation of carbon and water fluxes of forest ecosystems is of particular importance for addressing the problems originating from global environmental change, and providing helpful information about carbon and water content for analyzing and diagnosing past and future climate change. The main
[...] Read more.
Accurate estimation of carbon and water fluxes of forest ecosystems is of particular importance for addressing the problems originating from global environmental change, and providing helpful information about carbon and water content for analyzing and diagnosing past and future climate change. The main focus of the current work was to investigate the feasibility of four comparatively new methods, including generalized regression neural network, group method of data handling (GMDH), extreme learning machine and adaptive neuro-fuzzy inference system (ANFIS), for elucidating the carbon and water fluxes in a forest ecosystem. A comparison was made between these models and two widely used data-driven models, artificial neural network (ANN) and support vector machine (SVM). All the models were evaluated based on the following statistical indices: coefficient of determination, Nash-Sutcliffe efficiency, root mean square error and mean absolute error. Results indicated that the data-driven models are capable of accounting for most variance in each flux with the limited meteorological variables. The ANN model provided the best estimates for gross primary productivity (GPP) and net ecosystem exchange (NEE), while the ANFIS model achieved the best for ecosystem respiration (R), indicating that no single model was consistently superior to others for the carbon flux prediction. In addition, the GMDH model consistently produced somewhat worse results for all the carbon flux and evapotranspiration (ET) estimations. On the whole, among the carbon and water fluxes, all the models produced similar highly satisfactory accuracy for GPP, R and ET fluxes, and did a reasonable job of reproducing the eddy covariance NEE. Based on these findings, it was concluded that these advanced models are promising alternatives to ANN and SVM for estimating the terrestrial carbon and water fluxes. Full article
Figures

Figure 1

Open AccessArticle
Genetic Diversity and Structure of Natural Quercus variabilis Population in China as Revealed by Microsatellites Markers
Forests 2017, 8(12), 495; doi:10.3390/f8120495 -
Abstract
Quercus variabilis is a tree species of ecological and economic value that is widely distributed in China. To effectively evaluate, use, and conserve resources, we applied 25 pairs of simple sequence repeat (SSR) primers to study its genetic diversity and genetic structure in
[...] Read more.
Quercus variabilis is a tree species of ecological and economic value that is widely distributed in China. To effectively evaluate, use, and conserve resources, we applied 25 pairs of simple sequence repeat (SSR) primers to study its genetic diversity and genetic structure in 19 natural forest or natural secondary forest populations of Q. variabilis (a total of 879 samples). A total of 277 alleles were detected. Overall, the average expected heterozygosity (He) was 0.707 and average allelic richness (AR) was 7.79. Q. variabilis manifested a loss of heterozygosity, and the mean of inbreeding coefficient (FIS) was 0.044. Less differentiation among populations was observed, and the genetic differentiation coefficient (FST) was 0.063. Bayesian clustering analysis indicated that the 19 studied populations could be divided into three groups based on their genetic makeup, namely, the Southwest group, Central group, and Northeastern group. The Central group, compared to the populations of the Southwest and Northeast group, showed higher genetic diversities and lower genetic differentiations. As a widely distributed species, the historical migration of Q. variabilis contributed to its genetic differentiation. Full article
Figures

Figure 1

Open AccessArticle
Characterisation of Beaver Habitat Parameters That Promote the Use of Culverts as Dam Construction Sites: Can We Limit the Damage to Forest Roads?
Forests 2017, 8(12), 494; doi:10.3390/f8120494 -
Abstract
The use of forest roads as foundations for dam construction by beavers is a recurrent problem in the management of forest road networks. In order to limit the damage to forest roads, our goal was to calculate the probability of beaver dam installation
[...] Read more.
The use of forest roads as foundations for dam construction by beavers is a recurrent problem in the management of forest road networks. In order to limit the damage to forest roads, our goal was to calculate the probability of beaver dam installation on culverts, according to surrounding habitat parameters, which could allow for improvement in the spatial design of new roads that minimise conflicts with beavers. Comparisons of culverts with (n = 77) and without (n = 51) dams in northwestern Quebec showed that catchment surface, cumulate length of all local streams within a 2-km radius, and road embankment height had a negative effect on the probability of dam construction on culverts, while flow level and culvert diameter ratio had a positive effect. Nevertheless, predicted probabilities of dam construction on culverts generally exceeded 50%, even on sites that were less favourable to beavers. We suggest that it would be more reasonable to take their probable subsequent presence into account at the earliest steps of road conception. Installing mitigation measures such as pre-dams during road construction would probably reduce the occurrence of conflicts with beavers and thus reduce the maintenance costs of forest roads. Full article
Figures

Figure 1

Open AccessReview
Tropical and Highland Temperate Forest Plantations in Mexico: Pathways for Climate Change Mitigation and Ecosystem Services Delivery
Forests 2017, 8(12), 489; doi:10.3390/f8120489 -
Abstract
Forest plantations are a possible way of increasing forest productivity in temperate and tropical forests, and therefore also increasing above- and belowground carbon pools. In the context of climate change, monospecific plantations might become an alternative to mitigate global warming; however, their contribution
[...] Read more.
Forest plantations are a possible way of increasing forest productivity in temperate and tropical forests, and therefore also increasing above- and belowground carbon pools. In the context of climate change, monospecific plantations might become an alternative to mitigate global warming; however, their contribution to the structural complexity, complementarity, and biodiversity of forests has not been addressed. Mixed forest plantations can ensure that objectives of climate change mitigation are met through carbon sequestration, while also delivering anticipated ecosystem services (e.g., nutrient cycling, erosion control, and wildlife habitat). However, mixed forest plantations pose considerable operational challenges and research opportunities. For example, it is essential to know how many species or functional traits are necessary to deliver a set of benefits, or what mixture of species and densities are key to maintaining productive plantations and delivering multiple ecosystem services. At the same time, the establishment of forest plantations in Mexico should not be motivated solely by timber production. Forest plantations should also increase carbon sequestration, maintain biodiversity, and provide other ecosystem services. This article analyzes some matters that affect the development of planted forests in the Mexican national context, and presents alternatives for forest resources management through the recommendation of mixed forest plantations as a means of contributing to climate change mitigation and the delivery of ecosystem services. Full article
Figures

Figure 1

Open AccessPerspective
Adaptation to Climate Change in Forestry: A Perspective on Forest Ownership and Adaptation Responses
Forests 2017, 8(12), 493; doi:10.3390/f8120493 -
Abstract
Adaptation to climate change has often been discussed from the perspectives of social vulnerability and community vulnerability, recognising that characteristics at local level will influence the particular adaptations undertaken. However, the extent to which national-level systemic factors influence and shape measures defined as
[...] Read more.
Adaptation to climate change has often been discussed from the perspectives of social vulnerability and community vulnerability, recognising that characteristics at local level will influence the particular adaptations undertaken. However, the extent to which national-level systemic factors influence and shape measures defined as adaptations has seldom been recognised. Focusing on adaptation to climate change in forestry, this study uses the example of two countries in the northern hemisphere with different forest ownership structures, forestry industry and traditions: Sweden, with strong private, non-industrial ownership, dominant forest industry and long forestry traditions; and Scotland, with forest ownership dominated by large estates and investment forestry based on plantations of exotic conifer species. The study shows how adaptation to climate change is structurally embedded and conditioned, which has resulted in specific challenges and constraints for different groups of forest owners within these two different contexts. This produces a specific set of political spaces and policy tools by rendering climate change in relation to forestry manageable, negotiable and practical/logical in specific ways. It is recommended that the focus of future work on climate-related issues and development of adaptation measures and policy should not be primarily on climate-related factors, but on institutional analysis of structural factors and logics in target sectors, in order to critically explore concepts of agency and power within these processes. Full article
Open AccessArticle
Development of Multiplexed Marker Sets to Identify the Most Relevant Poplar Species for Breeding
Forests 2017, 8(12), 492; doi:10.3390/f8120492 -
Abstract
Within the genus Populus, about 30 species are classified into six sections, of which some are cross-compatible. Besides naturally occurring hybrids, huge breeding programs have led to a high number of artificially produced hybrids, for which the determination of genetically involved species
[...] Read more.
Within the genus Populus, about 30 species are classified into six sections, of which some are cross-compatible. Besides naturally occurring hybrids, huge breeding programs have led to a high number of artificially produced hybrids, for which the determination of genetically involved species by morphological characteristics is often difficult. This necessitates the use of molecular markers for the identification of both maternal as well as paternal species, and in the case of complex hybrids, the genealogy. For this reason, we developed new chloroplast and nuclear markers for the differentiation of up to 19 poplar species, with one to 32 individuals per species regularly used in breeding programs based on already known barcoding, other chloroplast regions, and nuclear genes of interest. We developed methods to identify species by either species-specific nucleotide variations or, when no initial information for the species was given, by using a set of markers either in a procedure of exclusion or in a multiplexed marker set. The developed markers can all be used with low-cost equipment, and some can additionally be applied using a genetic analyzer. We combined these markers in multiplexes for a very fast and easy-to-use application for the identification of poplar species and their hybrids. Full article
Figures

Figure 1

Open AccessArticle
Mapping Net Stocked Plantation Area for Small-Scale Forests in New Zealand Using Integrated RapidEye and LiDAR Sensors
Forests 2017, 8(12), 487; doi:10.3390/f8120487 -
Abstract
In New Zealand, approximately 70% of plantation forests are large-scale (over 1000 ha) with accurate resource description. In contrast, the remaining 30% of plantation forests are small-scale (less than 1000 ha). It is forecasted that these small-scale forests will supply nearly 40% of
[...] Read more.
In New Zealand, approximately 70% of plantation forests are large-scale (over 1000 ha) with accurate resource description. In contrast, the remaining 30% of plantation forests are small-scale (less than 1000 ha). It is forecasted that these small-scale forests will supply nearly 40% of the national wood production in the next decade. However, in-depth description of these forests, especially those under 100 ha, is very limited. This research evaluates the use of remote sensing datasets to map and estimate the net stocked plantation area for small-scale forests. We compared a factorial combination of two classification approaches (Nearest Neighbour (NN), Classification and Regression Tree (CART)) and two remote sensing datasets (RapidEye, RapidEye plus LiDAR) for their ability to accurately classify planted forest area. CART with a combination of RapidEye and LiDAR metrics outperformed the other three combinations producing the highest accuracy for mapping forest plantations (user’s accuracy = 90% and producer’s accuracy = 88%). This method was further examined by comparing the mapped plantations with manually digitised plantations based on aerial photography. The mapping approach overestimated the plantation area by 3%. It was also found that forest patches exceeding 10 ha achieved higher conformance with the digitised areas. Overall, the mapping approach in this research provided a proof of concept for deriving forest area and mapping boundaries using remote sensing data, and is especially relevant for small-scale forests where limited information is currently available. Full article
Figures

Figure 1

Open AccessArticle
Growth, Physiological, Biochemical, and Ionic Responses of Morus alba L. Seedlings to Various Salinity Levels
Forests 2017, 8(12), 488; doi:10.3390/f8120488 -
Abstract
Mulberry (Morus alba L.), a moderately salt-tolerant tree species, is considered to be economically important. In this study, 1-year-old mulberry seedlings cultivated in soil under greenhouse conditions were treated with five concentrations of sodium chloride (NaCl; 0%, 0.1%, 0.2%, 0.3%, and 0.5%)
[...] Read more.
Mulberry (Morus alba L.), a moderately salt-tolerant tree species, is considered to be economically important. In this study, 1-year-old mulberry seedlings cultivated in soil under greenhouse conditions were treated with five concentrations of sodium chloride (NaCl; 0%, 0.1%, 0.2%, 0.3%, and 0.5%) for 3 and 21 days. Plant growth parameters were not affected by 0.1% NaCl, but significant reductions were observed after treatment with 0.2%, 0.3%, and 0.5% NaCl. The malondialdehyde content and cell membrane stability of mulberry seedlings exposed to 0.1% NaCl did not change, indicating that mulberry is not significantly affected by low-salinity conditions. The Na contents of various organs did not increase significantly in response to 0.1% NaCl, but the K:Na, Mg:Na, and Ca:Na ratios of various organs were affected by NaCl. Marked changes in the levels of major compatible solutes (proline, soluble sugars, and soluble proteins) occurred in both the leaves and roots of NaCl-treated seedlings relative to control seedlings. Under severe saline conditions (0.5% NaCl), the ability of mulberry to synthesize enzymatic antioxidants may be impaired. Full article
Figures

Figure 1

Open AccessArticle
Association of Fruit and Seed Traits of Sapindus mukorossi Germplasm with Environmental Factors in Southern China
Forests 2017, 8(12), 491; doi:10.3390/f8120491 -
Abstract
Sapindus mukorossi is widely distributed in tropical and subtropical areas of southern China; the seed kernel oil is potential biodiesel material, and the saponins extracted from fruit pericarp are very valuable efficient natural surfactants. Therefore, S. mukorossi is an ideal tree species for
[...] Read more.
Sapindus mukorossi is widely distributed in tropical and subtropical areas of southern China; the seed kernel oil is potential biodiesel material, and the saponins extracted from fruit pericarp are very valuable efficient natural surfactants. Therefore, S. mukorossi is an ideal tree species for developing forestry bioenergy and multiple other products. In this study, 42 S. mukorossi fruits from mother trees were collected from 39 distinct locations in 12 Chinese provinces to infer fruit and seed trait responses to environmental factors. Canonical correspondence analysis (CCA) was conducted using 21 horticultural fruit traits and 10 environmental factors that represented different climatic and geographic conditions throughout southern China. CCA revealed well-developed patterns of natural phenotypic variation, and insight into the ecological factors that are potentially important in shaping this variation. The results presented here further elucidate the natural distribution and ecological adaptations of wild S. mukorossi resources, which will be valuable for S. mukorossi cultivation by helping identify ideal planting areas. The germplasm resources with extensive morphological variation can also contribute to S. mukorossi breeding in the future by helping develop new cultivars with high saponin yield. Full article
Figures

Figure 1

Open AccessArticle
Warming Effects on Pinus sylvestris in the Cold–Dry Siberian Forest–Steppe: Positive or Negative Balance of Trade?
Forests 2017, 8(12), 490; doi:10.3390/f8120490 -
Abstract
Understanding climate change impacts on drought-prone forests is a critical issue. We investigated ring-width and stable isotopes (Δ13C and δ18O) in two Pinus sylvestris stands of the cold–dry Siberian forest–steppe growing under contrasting climatic trends over the last 75
[...] Read more.
Understanding climate change impacts on drought-prone forests is a critical issue. We investigated ring-width and stable isotopes (Δ13C and δ18O) in two Pinus sylvestris stands of the cold–dry Siberian forest–steppe growing under contrasting climatic trends over the last 75 years. Despite regional warming, there was increasing precipitation during the growing period at the southern site (MIN) but increasing water deficit (WD) at the northern site (BER). Intrinsic water use efficiency (WUEi) increased similarly (ca. 22%) in response to warming and rising atmospheric CO2. However, the steady increase in WUEi was accompanied by divergent growth patterns since 1980: increasing basal area increment (BAI) in MIN (slope = 0.102 cm2 year−2) and decreasing BAI in BER (slope = −0.129 cm2 year−2). This suggests that increased precipitation, mediated by CO2 effects, promoted growth in MIN, whereas intensified drought stress led to decreased carbon gain and productivity in BER. When compared to warm–dry stands of eastern Spain, the WUEi dependence on WD was three-fold greater in Siberia. Conversely, BAI was more affected by the relative impact of water stress within each region. These results indicate contrasting future trajectories of P. sylvestris forests, which challenge forecasting growth and carbon sequestration in cold–dry areas. Full article
Figures

Figure 1

Open AccessArticle
Vicariance and Oceanic Barriers Drive Contemporary Genetic Structure of Widespread Mangrove Species Sonneratia alba J. Sm in the Indo-West Pacific
Forests 2017, 8(12), 483; doi:10.3390/f8120483 -
Abstract
Patterns of genetic structure are essential for a comprehensive understanding of the evolution and biogeography of a species. Here, we investigated the genetic patterns of one of the most widespread and abundant mangrove species in the Indo-West Pacific, Sonneratia alba J. Sm., in
[...] Read more.
Patterns of genetic structure are essential for a comprehensive understanding of the evolution and biogeography of a species. Here, we investigated the genetic patterns of one of the most widespread and abundant mangrove species in the Indo-West Pacific, Sonneratia alba J. Sm., in order to gain insights into the ecological and evolutionary drivers of genetic structure in mangroves. We employed 11 nuclear microsatellite loci and two chloroplast regions to genotyped 25 S. alba populations. Our objectives were to (1) assess the level of genetic diversity and its geographic distribution; and (2) determine the genetic structure of the populations. Our results revealed significant genetic differentiation among populations. We detected a major genetic break between Indo-Malesia and Australasia, and further population subdivision within each oceanic region in these two major clusters. The phylogeographic patterns indicated a strong influence of vicariance, oceanic barriers and geographic distance on genetic structure. In addition, we found low genetic diversity and high genetic drift at range edge. This study advances the scope of mangrove biogeography by demonstrating a unique scenario whereby a widespread species has limited dispersal and high genetic divergence among populations. Full article
Figures

Figure 1

Open AccessArticle
Use, Utilization, Productivity and Fuel Consumption of Purpose-Built and Excavator-Based Harvesters and Processors in Italy
Forests 2017, 8(12), 485; doi:10.3390/f8120485 -
Abstract
Annual use, utilization, productivity and fuel consumption of three purpose-built and three excavator-based harvesters and processors were monitored for one work year. All machines were owned and operated by private contractors and were representative of the Italian machine fleet. Despite challenging mountain terrain,
[...] Read more.
Annual use, utilization, productivity and fuel consumption of three purpose-built and three excavator-based harvesters and processors were monitored for one work year. All machines were owned and operated by private contractors and were representative of the Italian machine fleet. Despite challenging mountain terrain, annual use ranged from 675 to 1525 h per year, and production from 3200 to 27,400 m3 per year. Productivity was lower for excavator-based units, and for machines working under a yarder, due to limited yarder capacity. Purpose-built machines offered higher utilization, productivity and fuel efficiency compared with excavator-based machines. Fuel consumption per m3 was 2.4 times greater for excavator-based units, compared with purpose-built machines. Excavator-based units offered financial and technical advantages, but their long-term market success will likely depend on future improvements in fuel efficiency, in the face of increasing fuel prices. Full article
Figures

Figure 1