Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differen...Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differences in traits and functional diversity between forest edges and interiors,and how the inclusion of intraspecific trait variation affects the assessment of functional diversity in these habitats.We sampled 10 representative forest patches,and,in each patch,we established five plots on the edge and five inside the forest,collecting leaf functional traits,allometric and wood density for all species.We assessed functional diversity using functional richness(FRic),divergence(FDiv),and dispersion(FDis).To assess the impact of incorporating intraspecific variation when comparing trait values and functional diversity indices,we established two scenarios:one that excludes intraspecific variation and another that includes it.We found that the edge and interior harbor individuals with distinct functional traits that alleviate the inherent stress of each habitat.The edge was also found to be more selective in terms of the range of functional traits,resulting in lower functional diversity.Our findings demonstrated that habitats play an important role in intraspecific trait variation(ITV)and that statistically significant differences between habitats,in relation to traits and functional diversity,were better observed with the inclusion of intraspecific variation.Our study highlights the potential of using natural forest patches to understand the edge effect,regardless of habitat loss.Additionally,we emphasize the importance of incorporating ITV into functional diversity studies,especially those on a smaller scale that incorporate quantitative variables,to better understand and predict ecological patterns.展开更多
In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenan...In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.展开更多
Bamboo forest is an important forest type in subtropical and tropical areas.Due to its biological characteristic and growth habits, bamboo is not only an ideal economicinvestment that can be utilized in many different...Bamboo forest is an important forest type in subtropical and tropical areas.Due to its biological characteristic and growth habits, bamboo is not only an ideal economicinvestment that can be utilized in many different manners but also has enormous potential foralleviating many environmental problems facing the world today. This review describes ecologicalfunctions of the bamboo forest on soil erosion control, water conservation, land rehabilitation, andcarbon sequestration.展开更多
Permanent plots in the montane tropical rain forests in Xishuangbanna, southwest China, were established, and different empirical models, based on observation data of these plots in 1992, were built to model diameter ...Permanent plots in the montane tropical rain forests in Xishuangbanna, southwest China, were established, and different empirical models, based on observation data of these plots in 1992, were built to model diameter frequency distributions. The focus of this study is on predicting accuracy of stem number in the larger diameter classes, which is much more important than that of the smaller trees, from the view of forest management, and must be adequately considered in the modelling and estimate. There exist 3 traditional ways of modelling the diameter frequency distribution: the negative exponential function model, limiting line function model, and Weibull distribution model. In this study, a new model, named as the logarithmic J-shape function, together with the others, was experimented and was found as a more suitable model for modelling works in the tropical forests.展开更多
Background: Forest biodiversity is the foundation of many ecosystem services, and the effect of biodiversity on ecosystem functioning and processes (BEF) has been a central issue in biodiversity studies. Although m...Background: Forest biodiversity is the foundation of many ecosystem services, and the effect of biodiversity on ecosystem functioning and processes (BEF) has been a central issue in biodiversity studies. Although many hypotheses have been developed to interpret global gradients of biodiversity, there has not been complete agreement on mechanisms controlling biodiversity patterns and distributions. Differences may be due to limited observation data and inconsistencies of spatial scales in analysis. Methods: In this study, we take advantage of USDA Forest Service forest inventory and analysis (FIA) data for exploring regional forest biodiversity and BEF in New England forests. The FIA data provide detailed information of sampled plots and trees for the region, including 6000 FIA plots and more than 33,000 individual trees. Biodiversity models were used to analyze the data. Results: Tree species diversity increases from the north to the south at a rate about 2-3 species per latitudinal degree. Tree species diversity is better predicted by tree height than forest age or biomass. Very different distribution patterns of two common maple species, sugar maple (Acer sdcchorum) and red maple (Acer rubrum), highlight the vulnerability of sugar maple and its potential replacement by red maple on New England landscapes. Red maple generally already outperforms sugar maple, and will likely and continuously benefit from a changing climate in New England. Conclusions: We conclude that forest structure (height) and resources (biomass) are more likely foundational characteristics supporting biodiversity rather than biodiversity determining forest productivity and/or biomass. The potential replacement of red maple for sugar maple in the New England areas could affect biodiversity and stability of forest ecosystem functioning because sugar maple plays important ecological roles distinct from red maple that are beneficial to other tree species in northern hardwood forests. Such a change may not affect forest resilience in terms of forest productivity and biomass as these are similar in red maple and sugar maple, however, it would almost certainly alter forest structure across the landscape.展开更多
Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change.However,until now,these mec...Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change.However,until now,these mechanisms were poorly understood in the temperate forests of northeastern China,which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological resilience.Methods:In this study,we mapped functional diversity distributions using a Kriging Interpolation Method.A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity.Three piecewise structural equation models(pSEMs)with forest types as random effects were constructed for testing the direct effects of climate,and the indirect effects of stand structure on functional diversity across the large study region.Specific causal relationships in each forest type were also examined using 15 linear structural equation models.Results:Although environmental filtering by climate is important,stand structure explains most of the functional variation of the forest ecosystems in northeastern China.Our study thus only partially supports the stressdominance hypothesis.Several abundant species determine most of the functional diversity,which supports the mass ratio hypothesis.Conclusions:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity,especially regarding the mixing of coniferous and broad-leaved tree species.展开更多
The response of diversity and biomass of herbaceous functional groups along an altitudinal gradient in mountainous forests of southern Zagros,Khuzestan Province,Iran was studied by sampling vegetation in 30 circular 1...The response of diversity and biomass of herbaceous functional groups along an altitudinal gradient in mountainous forests of southern Zagros,Khuzestan Province,Iran was studied by sampling vegetation in 30 circular 1000-m^2 plots in herb layer of the forest floor within 646–2447 m asl(lowland:<1000 m asl,midland:1000–2000 m asl,highland:>2000 m asl).The most important herbaceous functional groups were classified based on two aspects of growth form:annuals–perennials,grasses–forbs.Then the relationship between the diversity,richness,evenness,biomass and elevation was analyzed.The results showed that the annual functional group in the low-and midland classes,and perennial functional group in the lowland class had the highest species diversity and evenness in annual and perennial functional groups,respectively(p<0.01).The perennials in the highland class had the maximum total,above-and belowground dry biomass(p<0.01).On the other hand,the forb functional group in the lowland class had the greatest species diversity,richness,and evenness(p<0.01)and in the highland class had the maximum total dry,above-and belowground dry biomass in the grass and forb functional groups(p<0.01).Increasing the diversity,richness,and species evenness resulted in a decrease in the plant dry biomass.展开更多
Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in...Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in Wenchang City was evaluated and analyzed.The results show that the total value of ecosystem service function of ecological public welfare forests in Wenchang City is about 4.020 billion yuan,of which storage capacity,water purification,soil fixation,fertilizer(N,P and K fertilizer) conservation,carbon sequestration,oxygen release,forest nutrient accumulation,providing anion,absorbing SO_2,absorbing fluoride,absorbing NxO,absorbing soil heavy metals,dust retention,noise reduction,sterilization,forest protection,forest biodiversity protection,and forest recreation(ecological tourism) are about 1.510 billion,582.256 million,3.769 million,268.220 million,116.360 million,2.747 million,22.682 million,42.817 million,1.722 million,74,600,131,900,187.918 million,77.409 million,28.721 million,43.090 million,180.696 million,571.036 million,and 108.677 million yuan展开更多
In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated...In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated by using the method of Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008). The results showed that in 2014, the total value of forest ecosystem service function in Kanas Nature Reserve increased by 7.34% compared with that in 2009, and the value of water conservation and biodiversity accounted for the largest proportion. The increasing rate of functional value of shrub forest land was obviously higher than that of coniferous forest land and broad-leaf forest land. The service function and value of different forest types were obviously different.展开更多
Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due ...Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory species.In this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present forests.In the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from 1965.Factors that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree analysis.The coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory layer.The abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always different.Although the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH increased.The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional.Functional group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession.展开更多
Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the r...Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the remote sensing technic,large-scale satellite data become available for surface monitoring.Due to the various information contained in the remote sensing data,obtain accurate plateau forest segmentation from the remote sensing imagery still remain challenges.Recent developed deep learning(DL)models such as deep convolutional neural network(CNN)has been widely used in image processing tasks,and shows possibility for remote sensing segmentation.However,due to the unique characteristics and growing environment of the plateau forest,generate feature with high robustness needs to design structures with high robustness.Aiming at the problem that the existing deep learning segmentation methods are difficult to generate the accurate boundary of the plateau forest within the satellite imagery,we propose a method of using boundary feature maps for collaborative learning.There are three improvements in this article.First,design a multi input model for plateau forest segmentation,including the boundary feature map as an additional input label to increase the amount of information at the input.Second,we apply a strong boundary search algorithm to obtain boundary value,and propose a boundary value loss function.Third,improve the Unet segmentation network and combine dense block to improve the feature reuse ability and reduces the image information loss of the model during training.We then demonstrate the utility of our method by detecting plateau forest regions from ZY-3 satellite regarding to Sanjiangyuan nature reserve.The experimental results show that the proposed method can utilize multiple feature information comprehensively which is beneficial to extracting information from boundary,and the detection accuracy is generally higher than several state-of-art algorithms.As a result of this investigation,the study will contribute in several ways to our understanding of DL for region detection and will provide a basis for further researches.展开更多
The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and surv...The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and survival.While the relationship between plant functional traits and tree growth performance has been extensively studied,the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood.This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China.The cross-species variations in tree growth rates were related to plant hydraulic traits(e.g.,vessel lumen diameter,xylem vessel density,stomatal density,and stomatal size)and leaf anatomical traits(e.g.,total leaf thickness,lower/upper epidermis thickness,and spongy thickness).The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree,which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season.In contrast,deciduous species showed no correlation between their functional traits and growth rate.The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.展开更多
The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,w...The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island.展开更多
Conservation and enhancement of old-growth forests are key in forest planning and policies.In order to do so,more knowledge is needed on how the attributes traditionally associated with old-growth forests are distribu...Conservation and enhancement of old-growth forests are key in forest planning and policies.In order to do so,more knowledge is needed on how the attributes traditionally associated with old-growth forests are distributed in space,what differences exist across distinct forest types and what natural or anthropic conditions are affecting the distribution of these old-growthness attributes.Using data from the Third Spanish National Forest Inventory(1997–2007),we calculated six indicators commonly associated with forest old-growthness for the plots in the territory of Peninsular Spain and Balearic Islands,and then combined them into an aggregated index.We then assessed their spatial distribution and the differences across five forest functional types,as well as the effects of ten climate,topographic,landscape,and anthropic variables in their distribution.Relevant geographical patterns were apparent,with climate factors,namely temperature and precipitation,playing a crucial role in the distribution of these attributes.The distribution of the indicators also varied across different forest types,while the effects of recent anthropic impacts were weaker but still relevant.Aridity seemed to be one of the main impediments for the development of old-growthness attributes,coupled with a negative impact of recent human pressure.However,these effects seemed to be mediated by other factors,specially the legacies imposed by the complex history of forest management practices,land use changes and natural disturbances that have shaped the forests of Spain.The results of this exploratory analysis highlight on one hand the importance of climate in the dynamic of forests towards old-growthness,which is relevant in a context of Climate Change,and on the other hand,the need for more insights on the history of our forests in order to understand their present and future.展开更多
Increasing human activity is altering the struc-ture of forests,which affects the composition of communi-ties,including birds.However,little is known about the key forest structure variables that determine the richnes...Increasing human activity is altering the struc-ture of forests,which affects the composition of communi-ties,including birds.However,little is known about the key forest structure variables that determine the richness of bird communities in European temperate oak forests.We,there-fore,aimed to identify key variables in these habitats that could contribute to the design of management strategies for forest conservation by surveying 11 oak-dominated forest sites throughout the mid-mountain range of Hungary at 86 survey points to reveal the role of different compositional and structural variables for forest stands that influence the breeding bird assemblages in the forests at the functional group and individual species levels.Based on decision tree modelling,our results showed that the density of trees larger than 30 cm DBH was an overall important variable,indi-cating that large-diameter trees were essential to provide diverse bird communities.The total abundance of birds,the foliage-gleaners,primary and secondary cavity nest-ers,residents,and five specific bird species were related to the density of high trunk diameter trees.The abundance of shrub nesters was negatively influenced by a high density of trees over 10 cm DBH.The density of the shrub layer positively affected total bird abundance and the abundance of foliage gleaners,secondary cavity nesters and residents.Analysis of the co-dominant tree species showed that the presence of linden,beech,and hornbeam was important in influencing the abundance of various bird species,e.g.,Eur-asian Treecreeper(Certhia familiaris),Marsh Tit(Poecile palustris)and Wood Warbler(Phylloscopus sibilatrix).Our results indicated that large trees,high tree diversity,and dense shrub layer were essential for forest bird communities and are critical targets for protection to maintain diverse and abundant bird communities in oak-dominated forest habitats.展开更多
As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecologi...As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecological integrity,explore its latitudinal patterns,and identify the potential determinants behind it.We selected 15 indicators of forest composition,structure,and function and used two approaches to quantify ecological integrity.The results show a significant negative correlation between forest ecological integrity and increasing latitude.Climate emerged as the main driver of the latitudinal pattern compared to anthropogenic and other influencing factors.Our study offers a new approach to quantifying ecological integrity based on a set of indicators that may help assess the contribution of forest ecosystems in conservation,restoration,and ecosystem services.展开更多
Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental condit...Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.展开更多
Tropical forests,critical for global carbon storage and biodiversity,are failing to adapt at the pace required by accelerating climate change.A comprehensive study by Aguirre-Gutiérrez et al.(Science 387:eadi5414...Tropical forests,critical for global carbon storage and biodiversity,are failing to adapt at the pace required by accelerating climate change.A comprehensive study by Aguirre-Gutiérrez et al.(Science 387:eadi5414,2025)analyzing four decades of data from 415 forest plots and 250,000 trees across the Americas reveals significant mismatches between functional trait shifts(e.g.,leaf area,wood density,photosynthetic capacity)and climatic pressures.Survivor trees tracked climatic changes at less than 8%of the necessary rate,while recruits achieved only 22%,leaving ecosystems increasingly vulnerable.Lowland forests exhibited stronger trait responses compared to nutrient-limited montane forests,but neither aligned with future climate projections.By 2100,projected temperature rises(~4℃)and precipitation declines(~20%)may push forests into“no-analog”climates,surpassing adaptive thresholds.These lags threaten carbon sequestration,biodiversity,and ecosystem stability,underscoring the urgent need for emissions reduction,conservation of climate refugia,and assisted migration strategies to mitigate irreversible biome transitions.展开更多
We analyzed changes in seven functional traits of dominant herbaceous vascular plant species in 14 plant communities across an elevation gradient at the Northern Urals:plant height(PH),leaf area(LA),leaf dry mass(LDM)...We analyzed changes in seven functional traits of dominant herbaceous vascular plant species in 14 plant communities across an elevation gradient at the Northern Urals:plant height(PH),leaf area(LA),leaf dry mass(LDM),leaf dry matter content(LDMC),specific leaf area(SLA),leaf nitrogen content(LNC)and leaf carbon content(LCC).The study plots were located at one catena with elevation range from 220 to 905 m above sea level,and covered three vegetation types:forest,open woodland and mountain tundra.The community-weighted means for PH,LA and SLA were found to decrease,while LDMC and LCC increased with elevation.This was due to an increase in the proportion of stress-tolerant plant species with small physical size and conservative strategy in the leaf economic spectrum in the most elevated mountain tundra communities.The variability of PH,LDMC,and SLA decreased with increasing elevation and deteriorating of ecological conditions,which is consistent with the stress-dominance hypothesis.The variability of the other traits did not show clear trends.Changes in species composition explained 57%-94%of the observed variability of functional traits for plant communities on the elevation gradient while intraspecific changes explained only 2%to 21%of the total variability.This provides a theoretical background for using functional traits derived from global databases and those measured in habitats with similar ecological characteristics in local-scale studies.展开更多
Silicon carbide(core third-generation wide-bandgap semiconductor)nanowires have superior characteristics and vital engineering potential in microelectric and photonic devices operating in harsh high-temperature and st...Silicon carbide(core third-generation wide-bandgap semiconductor)nanowires have superior characteristics and vital engineering potential in microelectric and photonic devices operating in harsh high-temperature and strong-irradiation environments.Herein,the dense monocrystalline forest-like 4H-and 6H-SiC nanowires(intrinsically bound as a single crystal)are fabricated using the top–down peeling method.They exhibit broadband light emissions spanning the red–green–blue spectral region.The naturally formed microcavity encapsulating the SiC nanowires yields discrete and multimodal emission lines;the luminescence lifetimes decrease to the order of picoseconds owing to improved photon density of states in the microcavity by the quantum electrodynamic Purcell effect.The measured Purcell factor of 8.35 agrees well with the theoretical value of 8.6.The low-temperature luminescence and work functions show significant dependence on the nanowire polytype.The luminescence exhibits peculiar staircase-function enhancement when the temperature is elevated to 200 K,owing to suppression of nonradiative transition channels.展开更多
基金the Brazilian Coordination for the Improvement of Higher Education Personnel (CAPES) by granting the scholarship (Finance Code 001)supported by the Brazilian National Council for Scientific and Technological Development (CNPq, project number 433828/2018-8,435598/2018-0)+1 种基金the Minas Gerais Research Funding Foundation (FAPEMIG, project number CRA APQ 00929-15)CNPq productivity fellowships
文摘Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differences in traits and functional diversity between forest edges and interiors,and how the inclusion of intraspecific trait variation affects the assessment of functional diversity in these habitats.We sampled 10 representative forest patches,and,in each patch,we established five plots on the edge and five inside the forest,collecting leaf functional traits,allometric and wood density for all species.We assessed functional diversity using functional richness(FRic),divergence(FDiv),and dispersion(FDis).To assess the impact of incorporating intraspecific variation when comparing trait values and functional diversity indices,we established two scenarios:one that excludes intraspecific variation and another that includes it.We found that the edge and interior harbor individuals with distinct functional traits that alleviate the inherent stress of each habitat.The edge was also found to be more selective in terms of the range of functional traits,resulting in lower functional diversity.Our findings demonstrated that habitats play an important role in intraspecific trait variation(ITV)and that statistically significant differences between habitats,in relation to traits and functional diversity,were better observed with the inclusion of intraspecific variation.Our study highlights the potential of using natural forest patches to understand the edge effect,regardless of habitat loss.Additionally,we emphasize the importance of incorporating ITV into functional diversity studies,especially those on a smaller scale that incorporate quantitative variables,to better understand and predict ecological patterns.
基金Supported by Special Funds for Central Financial to Support the Local Colleges and Universities([2013]389)~~
文摘In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.
基金This paper was supported by International Tropical Timber Organization (ITTO) (No. PD10/00REV.2(I,F)) and National Natural Science Foundation of China (No. 30300273).
文摘Bamboo forest is an important forest type in subtropical and tropical areas.Due to its biological characteristic and growth habits, bamboo is not only an ideal economicinvestment that can be utilized in many different manners but also has enormous potential foralleviating many environmental problems facing the world today. This review describes ecologicalfunctions of the bamboo forest on soil erosion control, water conservation, land rehabilitation, andcarbon sequestration.
文摘Permanent plots in the montane tropical rain forests in Xishuangbanna, southwest China, were established, and different empirical models, based on observation data of these plots in 1992, were built to model diameter frequency distributions. The focus of this study is on predicting accuracy of stem number in the larger diameter classes, which is much more important than that of the smaller trees, from the view of forest management, and must be adequately considered in the modelling and estimate. There exist 3 traditional ways of modelling the diameter frequency distribution: the negative exponential function model, limiting line function model, and Weibull distribution model. In this study, a new model, named as the logarithmic J-shape function, together with the others, was experimented and was found as a more suitable model for modelling works in the tropical forests.
基金the project NRS-6“Climate,Fire,and Carbon Cycle Sciences”supported by the USDA Forest ServiceBeijing Forestry University for covering the trip to the conference and generous conference venue facilitating this study
文摘Background: Forest biodiversity is the foundation of many ecosystem services, and the effect of biodiversity on ecosystem functioning and processes (BEF) has been a central issue in biodiversity studies. Although many hypotheses have been developed to interpret global gradients of biodiversity, there has not been complete agreement on mechanisms controlling biodiversity patterns and distributions. Differences may be due to limited observation data and inconsistencies of spatial scales in analysis. Methods: In this study, we take advantage of USDA Forest Service forest inventory and analysis (FIA) data for exploring regional forest biodiversity and BEF in New England forests. The FIA data provide detailed information of sampled plots and trees for the region, including 6000 FIA plots and more than 33,000 individual trees. Biodiversity models were used to analyze the data. Results: Tree species diversity increases from the north to the south at a rate about 2-3 species per latitudinal degree. Tree species diversity is better predicted by tree height than forest age or biomass. Very different distribution patterns of two common maple species, sugar maple (Acer sdcchorum) and red maple (Acer rubrum), highlight the vulnerability of sugar maple and its potential replacement by red maple on New England landscapes. Red maple generally already outperforms sugar maple, and will likely and continuously benefit from a changing climate in New England. Conclusions: We conclude that forest structure (height) and resources (biomass) are more likely foundational characteristics supporting biodiversity rather than biodiversity determining forest productivity and/or biomass. The potential replacement of red maple for sugar maple in the New England areas could affect biodiversity and stability of forest ecosystem functioning because sugar maple plays important ecological roles distinct from red maple that are beneficial to other tree species in northern hardwood forests. Such a change may not affect forest resilience in terms of forest productivity and biomass as these are similar in red maple and sugar maple, however, it would almost certainly alter forest structure across the landscape.
基金supported by the Program of National Natural Science Foundation of China(No.31971650)the Key Project of National Key Research and Development Plan(No.2017YFC0504104)Beijing Forestry University Outstanding Young Talent Cultivation Project(No.2019JQ03001)
文摘Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change.However,until now,these mechanisms were poorly understood in the temperate forests of northeastern China,which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological resilience.Methods:In this study,we mapped functional diversity distributions using a Kriging Interpolation Method.A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity.Three piecewise structural equation models(pSEMs)with forest types as random effects were constructed for testing the direct effects of climate,and the indirect effects of stand structure on functional diversity across the large study region.Specific causal relationships in each forest type were also examined using 15 linear structural equation models.Results:Although environmental filtering by climate is important,stand structure explains most of the functional variation of the forest ecosystems in northeastern China.Our study thus only partially supports the stressdominance hypothesis.Several abundant species determine most of the functional diversity,which supports the mass ratio hypothesis.Conclusions:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity,especially regarding the mixing of coniferous and broad-leaved tree species.
基金funding of project is supported by Lorestan University,Iran。
文摘The response of diversity and biomass of herbaceous functional groups along an altitudinal gradient in mountainous forests of southern Zagros,Khuzestan Province,Iran was studied by sampling vegetation in 30 circular 1000-m^2 plots in herb layer of the forest floor within 646–2447 m asl(lowland:<1000 m asl,midland:1000–2000 m asl,highland:>2000 m asl).The most important herbaceous functional groups were classified based on two aspects of growth form:annuals–perennials,grasses–forbs.Then the relationship between the diversity,richness,evenness,biomass and elevation was analyzed.The results showed that the annual functional group in the low-and midland classes,and perennial functional group in the lowland class had the highest species diversity and evenness in annual and perennial functional groups,respectively(p<0.01).The perennials in the highland class had the maximum total,above-and belowground dry biomass(p<0.01).On the other hand,the forb functional group in the lowland class had the greatest species diversity,richness,and evenness(p<0.01)and in the highland class had the maximum total dry,above-and belowground dry biomass in the grass and forb functional groups(p<0.01).Increasing the diversity,richness,and species evenness resulted in a decrease in the plant dry biomass.
基金Sponsored by Subsidy for the Running of National Positioning Observation Station of Forest Ecosystems in Wenchang City of Hainan Province(2015-LYPT-DW-095)
文摘Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in Wenchang City was evaluated and analyzed.The results show that the total value of ecosystem service function of ecological public welfare forests in Wenchang City is about 4.020 billion yuan,of which storage capacity,water purification,soil fixation,fertilizer(N,P and K fertilizer) conservation,carbon sequestration,oxygen release,forest nutrient accumulation,providing anion,absorbing SO_2,absorbing fluoride,absorbing NxO,absorbing soil heavy metals,dust retention,noise reduction,sterilization,forest protection,forest biodiversity protection,and forest recreation(ecological tourism) are about 1.510 billion,582.256 million,3.769 million,268.220 million,116.360 million,2.747 million,22.682 million,42.817 million,1.722 million,74,600,131,900,187.918 million,77.409 million,28.721 million,43.090 million,180.696 million,571.036 million,and 108.677 million yuan
基金Sponsored by Monitoring and Assessment of Forestry Ecological Service Function in Xinjiang(xjlk(2013)001)Open Fund of Forest Ecosystem Positioning Research Station in Altai mountain,Xinjiang
文摘In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated by using the method of Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008). The results showed that in 2014, the total value of forest ecosystem service function in Kanas Nature Reserve increased by 7.34% compared with that in 2009, and the value of water conservation and biodiversity accounted for the largest proportion. The increasing rate of functional value of shrub forest land was obviously higher than that of coniferous forest land and broad-leaf forest land. The service function and value of different forest types were obviously different.
基金supported by the Natural Science Foundation of Yunnan Province(Grant No:202301AT070356)the Open Fund of the Key Laboratory of Tropical Forest Ecology,Chinese Academy of Sciences,National Science Foundation of China(Grant No.32061123003)+1 种基金the Joint Fund of the National Natural Science Foundation of China-Yunnan Province(Grant No.U1902203)the Field Station Foundation of the Chinese Academy of Sciences.
文摘Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory species.In this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present forests.In the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from 1965.Factors that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree analysis.The coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory layer.The abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always different.Although the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH increased.The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional.Functional group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession.
基金supported by the following funds:Basic Research Program of Qinghai Province under Grants No.2020-ZJ-709National Key R&D Program of China (2018YFF01010100)+1 种基金Natural Science Foundation of Beijing (4212001)Advanced information network Beijing laboratory (PXM2019_014204_500029).
文摘Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the remote sensing technic,large-scale satellite data become available for surface monitoring.Due to the various information contained in the remote sensing data,obtain accurate plateau forest segmentation from the remote sensing imagery still remain challenges.Recent developed deep learning(DL)models such as deep convolutional neural network(CNN)has been widely used in image processing tasks,and shows possibility for remote sensing segmentation.However,due to the unique characteristics and growing environment of the plateau forest,generate feature with high robustness needs to design structures with high robustness.Aiming at the problem that the existing deep learning segmentation methods are difficult to generate the accurate boundary of the plateau forest within the satellite imagery,we propose a method of using boundary feature maps for collaborative learning.There are three improvements in this article.First,design a multi input model for plateau forest segmentation,including the boundary feature map as an additional input label to increase the amount of information at the input.Second,we apply a strong boundary search algorithm to obtain boundary value,and propose a boundary value loss function.Third,improve the Unet segmentation network and combine dense block to improve the feature reuse ability and reduces the image information loss of the model during training.We then demonstrate the utility of our method by detecting plateau forest regions from ZY-3 satellite regarding to Sanjiangyuan nature reserve.The experimental results show that the proposed method can utilize multiple feature information comprehensively which is beneficial to extracting information from boundary,and the detection accuracy is generally higher than several state-of-art algorithms.As a result of this investigation,the study will contribute in several ways to our understanding of DL for region detection and will provide a basis for further researches.
基金financially funded by the National Natural Science Foundation of China(3186113307,31770533,31870591)the West Light Talent Program of the Chinese Academy of Sciences(xbzg-zdsys-202218).
文摘The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and survival.While the relationship between plant functional traits and tree growth performance has been extensively studied,the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood.This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China.The cross-species variations in tree growth rates were related to plant hydraulic traits(e.g.,vessel lumen diameter,xylem vessel density,stomatal density,and stomatal size)and leaf anatomical traits(e.g.,total leaf thickness,lower/upper epidermis thickness,and spongy thickness).The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree,which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season.In contrast,deciduous species showed no correlation between their functional traits and growth rate.The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.
文摘The integrated value of the ecological function of tropical forests in the central mountainous areas of Hainan Island was 33.064 8 billion yuan/a in 2010(soil improvement,soil consolidation,soil nutrient maintenance,water storage and moisture regulation,water purification,carbon sequestration,oxygen releasing,air purification,biodiversity conservation,eco-tourism),equivalent to 16.1%of GDP in Hainan Province this year(205.212 billion yuan).The tropical forests in the central mountainous areas of Hainan Island make great contribution to Hainan Island's ecology,and play an important role in maintaining the stability of the ecological environment in Hainan Island.Through the understanding of major ecological function value of tropical forests,it is necessary to make people cherish the tropical forests in the central ecological function conservation areas of Hainan Province,and spontaneously throw themselves into the ecological environment protection and construction,to promote the rapid and sustainable development of construction in Hainan Province as an international tourism island.
基金supported by the Spanish Ministry of Science and Innovation project GREEN-RISK(Evaluation of past changes in ecosystem services and biodiversity in forests and restoration priorities under global change impacts-PID2020-119933RB-C21)A.C.received a pre-doctoral fellowship funded by the Spanish Ministry of Science and Innovation(PRE2021-099642).
文摘Conservation and enhancement of old-growth forests are key in forest planning and policies.In order to do so,more knowledge is needed on how the attributes traditionally associated with old-growth forests are distributed in space,what differences exist across distinct forest types and what natural or anthropic conditions are affecting the distribution of these old-growthness attributes.Using data from the Third Spanish National Forest Inventory(1997–2007),we calculated six indicators commonly associated with forest old-growthness for the plots in the territory of Peninsular Spain and Balearic Islands,and then combined them into an aggregated index.We then assessed their spatial distribution and the differences across five forest functional types,as well as the effects of ten climate,topographic,landscape,and anthropic variables in their distribution.Relevant geographical patterns were apparent,with climate factors,namely temperature and precipitation,playing a crucial role in the distribution of these attributes.The distribution of the indicators also varied across different forest types,while the effects of recent anthropic impacts were weaker but still relevant.Aridity seemed to be one of the main impediments for the development of old-growthness attributes,coupled with a negative impact of recent human pressure.However,these effects seemed to be mediated by other factors,specially the legacies imposed by the complex history of forest management practices,land use changes and natural disturbances that have shaped the forests of Spain.The results of this exploratory analysis highlight on one hand the importance of climate in the dynamic of forests towards old-growthness,which is relevant in a context of Climate Change,and on the other hand,the need for more insights on the history of our forests in order to understand their present and future.
基金supported part ia l l y by LIFE4Oak Forests Project LIFE16NAT/IT/000245)the RRF 2.3.121202200008 projectthe MERLiN project funded under the European Commission H2020 Programme(101036337 MERLiN H2020 LC GD 2020)。
文摘Increasing human activity is altering the struc-ture of forests,which affects the composition of communi-ties,including birds.However,little is known about the key forest structure variables that determine the richness of bird communities in European temperate oak forests.We,there-fore,aimed to identify key variables in these habitats that could contribute to the design of management strategies for forest conservation by surveying 11 oak-dominated forest sites throughout the mid-mountain range of Hungary at 86 survey points to reveal the role of different compositional and structural variables for forest stands that influence the breeding bird assemblages in the forests at the functional group and individual species levels.Based on decision tree modelling,our results showed that the density of trees larger than 30 cm DBH was an overall important variable,indi-cating that large-diameter trees were essential to provide diverse bird communities.The total abundance of birds,the foliage-gleaners,primary and secondary cavity nest-ers,residents,and five specific bird species were related to the density of high trunk diameter trees.The abundance of shrub nesters was negatively influenced by a high density of trees over 10 cm DBH.The density of the shrub layer positively affected total bird abundance and the abundance of foliage gleaners,secondary cavity nesters and residents.Analysis of the co-dominant tree species showed that the presence of linden,beech,and hornbeam was important in influencing the abundance of various bird species,e.g.,Eur-asian Treecreeper(Certhia familiaris),Marsh Tit(Poecile palustris)and Wood Warbler(Phylloscopus sibilatrix).Our results indicated that large trees,high tree diversity,and dense shrub layer were essential for forest bird communities and are critical targets for protection to maintain diverse and abundant bird communities in oak-dominated forest habitats.
基金funded by the National Key R&D Program of China(No.2023YFF1304001-01)the Program of National Natural Science Foundation of China(No.32371870)。
文摘As the impact of climate change and anthropogenic disturbance continues to intensify around the world,the ecological integrity(EI)of forest ecosystems is compromised in various ways.This study aims to quantify ecological integrity,explore its latitudinal patterns,and identify the potential determinants behind it.We selected 15 indicators of forest composition,structure,and function and used two approaches to quantify ecological integrity.The results show a significant negative correlation between forest ecological integrity and increasing latitude.Climate emerged as the main driver of the latitudinal pattern compared to anthropogenic and other influencing factors.Our study offers a new approach to quantifying ecological integrity based on a set of indicators that may help assess the contribution of forest ecosystems in conservation,restoration,and ecosystem services.
基金funded by the National Research,Development and Innovation Office(NKFIH FK 142428 grant)The contribution of Z.B.was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences and by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-5-SZTE-697)+2 种基金K.F.was supported by the New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research,Development and Innovation Fund(ÚNKP-23-3-SZTE-441)C.T.was supported by the NKFIH K 146137 grantA.E-V.was supported by the long-term research development project of the Czech Academy of Sciences(RVO 67985939).
文摘Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies.
基金supported by Central Government Guided Local Science and Technology Development Fund(2024ZY0616),the China Agricultural Journal Website Research Fund Project(CAJW2024-045).
文摘Tropical forests,critical for global carbon storage and biodiversity,are failing to adapt at the pace required by accelerating climate change.A comprehensive study by Aguirre-Gutiérrez et al.(Science 387:eadi5414,2025)analyzing four decades of data from 415 forest plots and 250,000 trees across the Americas reveals significant mismatches between functional trait shifts(e.g.,leaf area,wood density,photosynthetic capacity)and climatic pressures.Survivor trees tracked climatic changes at less than 8%of the necessary rate,while recruits achieved only 22%,leaving ecosystems increasingly vulnerable.Lowland forests exhibited stronger trait responses compared to nutrient-limited montane forests,but neither aligned with future climate projections.By 2100,projected temperature rises(~4℃)and precipitation declines(~20%)may push forests into“no-analog”climates,surpassing adaptive thresholds.These lags threaten carbon sequestration,biodiversity,and ecosystem stability,underscoring the urgent need for emissions reduction,conservation of climate refugia,and assisted migration strategies to mitigate irreversible biome transitions.
基金the framework of the budget theme No:125021902460-2。
文摘We analyzed changes in seven functional traits of dominant herbaceous vascular plant species in 14 plant communities across an elevation gradient at the Northern Urals:plant height(PH),leaf area(LA),leaf dry mass(LDM),leaf dry matter content(LDMC),specific leaf area(SLA),leaf nitrogen content(LNC)and leaf carbon content(LCC).The study plots were located at one catena with elevation range from 220 to 905 m above sea level,and covered three vegetation types:forest,open woodland and mountain tundra.The community-weighted means for PH,LA and SLA were found to decrease,while LDMC and LCC increased with elevation.This was due to an increase in the proportion of stress-tolerant plant species with small physical size and conservative strategy in the leaf economic spectrum in the most elevated mountain tundra communities.The variability of PH,LDMC,and SLA decreased with increasing elevation and deteriorating of ecological conditions,which is consistent with the stress-dominance hypothesis.The variability of the other traits did not show clear trends.Changes in species composition explained 57%-94%of the observed variability of functional traits for plant communities on the elevation gradient while intraspecific changes explained only 2%to 21%of the total variability.This provides a theoretical background for using functional traits derived from global databases and those measured in habitats with similar ecological characteristics in local-scale studies.
基金supported by the National Natural Science Foundation of China(Grant No.12274076).
文摘Silicon carbide(core third-generation wide-bandgap semiconductor)nanowires have superior characteristics and vital engineering potential in microelectric and photonic devices operating in harsh high-temperature and strong-irradiation environments.Herein,the dense monocrystalline forest-like 4H-and 6H-SiC nanowires(intrinsically bound as a single crystal)are fabricated using the top–down peeling method.They exhibit broadband light emissions spanning the red–green–blue spectral region.The naturally formed microcavity encapsulating the SiC nanowires yields discrete and multimodal emission lines;the luminescence lifetimes decrease to the order of picoseconds owing to improved photon density of states in the microcavity by the quantum electrodynamic Purcell effect.The measured Purcell factor of 8.35 agrees well with the theoretical value of 8.6.The low-temperature luminescence and work functions show significant dependence on the nanowire polytype.The luminescence exhibits peculiar staircase-function enhancement when the temperature is elevated to 200 K,owing to suppression of nonradiative transition channels.