Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,sp...Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,species physiological response and distribution can be correlated positively or negatively.The consistency of such correlation relationships at different spatial scales determines whether species responses derived from local scales can be extrapo-lated to broader spatial scales.In this study,we used a coupled modeling approach that coupled a plot-level ecosystem process model (LINKAGES) with a spatially explicit landscape model (LANDIS).We investigated species physio-logical responses and distribution responses to climate warming at the local,zonal and landscape scales respectively,and examined how species physiological response and distribution correlated at each corresponding scale and whether the correlations were consistent among these scales.The results indicate that for zonal and warming-sensitive species,the correlations between species physiological response and distribution are consistent at these spatial scales,and therefore the research results of vegetation response to climate warming at the local scale can be extrapolated to the zonal and landscape scales.By contrast,for zonal and warming-insensitive species the correlations among different spatial scales are consistent at some spatial scales but at other scales.The results also suggest that the results of azonal species at the local scale near their distribution boundaries can not be extrapolated simply to broader scales due to stronger responses to climate warming in those boundary regions.展开更多
The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland p...The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland plant biomass from 1980 to 2021.By examining 1134 observations from 182 published papers on wetland ecosystems,we created a comprehensive database of wetland plant above-ground biomass(AGB)and below-ground biomass(BGB).Using this database,we analyzed the biomass characteristics of different climate zones,wetland types and plant species globally.Based on this,we analyzed the differences between the biomass of different plant species and the linkage between AGB and BGB and organic carbon.Our study has revealed that wetland plant AGB is greater in equatorial regions but BGB is highest in polar areas,and lowest in arid and equatorial zones.For plant species,the BGB of the Poales is higher than the AGB but Caryophyllales,Cyperales and Lamiales have higher AGB.Moreover,our findings indicate that BGB plays a more significant role in contributing to the organic carbon pool compared to AGB.Notably,when BGB is less than 1 t C ha^(-1),even slight changes in biomass can have a significant impact on the organic carbon pool.And we observed that the SOC increases by 5.7 t C ha^(-1)when the BGB content is low,indicating that the SOC is more sensitive to changes in biomass under such circumstances.Our study provides a basis for the global response of AGB and BGB of wetland plants to organic carbon.展开更多
Aims Unmanned aerial vehicles(UAVs),i.e.drones,have recently emerged as cost-effective and flexible tools for acquiring remote sensing data with fine spatial and temporal resolution.It provides a new method and opport...Aims Unmanned aerial vehicles(UAVs),i.e.drones,have recently emerged as cost-effective and flexible tools for acquiring remote sensing data with fine spatial and temporal resolution.It provides a new method and opportunity for plant ecologists to study issues from individual to regional scales.However,as a new method,UAVs remote sensing applications in plant ecology are still challenged.The needs of plant ecology research and the application development of UAVs remote sensing should be better integrated.Methods This report provides a comprehensive review of UAV-based remote sensing applications in plant ecology to synthesize prospects of applying drones to advance plant ecology research.Important Findings Of the 400 references,59%were published in remote sensing journals rather than in plant ecology journals,reflecting a substantial gap between the interests of remote sensing experts and plant ecologists.Most of the studies focused on UAV remote sensing’s technical aspects,such as data processing and remote sensing inversion,with little attention on answering ecological questions.There were 61%of studies involved community-scale research.RGB and multispectral cameras were the most used sensors(75%).More ecologically meaningful parameters can be extracted from UAV data to better understand the canopy surface irregularity and community heterogeneity,identify geometrical characteristics of canopy gaps and construct canopy chemical assemblies from living vegetation volumes.More cooperation between plant ecologists and remote sensing experts is needed to promote UAV remote sensing in advancing plant ecology research.展开更多
Urban biodiversity is now recognized as playing a critical role in supporting global biodiversity.However,it is important to note that biodiversity is a systematic and holistic concept and prior studies have not gener...Urban biodiversity is now recognized as playing a critical role in supporting global biodiversity.However,it is important to note that biodiversity is a systematic and holistic concept and prior studies have not generally focused on cross-border or multi-scale management problems.On one hand,the ecosystems of cities are interconnected with adjacent cities by natural landscapes,so they are like mosaics instead of being isolated.Urban biodiversity research demands the consideration of the continuity within an ecosystem.On the other hand,both active protection and passive restoration strategies for urban biodiversity should not only be developed by researchers or municipal government agencies,but more importantly,they should consider the real ecosystem management problems faced by multi-scale departments in order to build a practicable Pressure-State-Response(PSR)model.The solutions for these issues should be included in the analysis to form a complete and more effective urban biodiversity strategy.The study in this paper offers an answer to whether different scales of cities or districts should adopt the same biodiversity strategy;and therefore,the decision depends on whether the places are of the same importance to the global or regional ecosystem,or whether the ecological elements are connected to the adjacent cities/districts and the problems that multiple stakeholders care about.展开更多
Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments;yet,it remains poorly understood how patterns of biomass allocation respond to nit...Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments;yet,it remains poorly understood how patterns of biomass allocation respond to nitrogen(N)additions across terrestrial ecosystems worldwide.Methods We conducted a meta-analysis using 5474 pairwise observations from 333 articles to assess how N addition affected plant biomass and biomass allocation among different organs.We also tested the'ratio-based optimal partitioning'vs.the'isometric allocation,hypotheses to explain potential N addition effects on biomass allocation.Important Findings We found that(i)N addition significantly increased whole plant biomass and the biomass of different organs,but decreased rootrshoot ratio(RS)and root mass fraction(RMF)while no effects of N addition on leaf mass fraction and stem mass fraction at the global scale;(ii)the effects of N addition on ratio-based biomass allocation were mediated by individual or interactive effects of moderator variables such as experimental conditions,plant functional types,latitudes and rates of N addition and(iii)N addition did not affect allometric relationships among different organs,suggesting that decreases in RS and RMF may result from isometric allocation patterns following increases in whole plant biomass.Despite alteration of ratio-based biomass allocation between root and shoot by N addition,the unaffected allometric scaling relationships among different organs(including root vs.shoot)suggest that plant biomass allocation patterns are more appropriately explained by the isometric allocation hypothesis rather than the optimal partitioning hypothesis.Our findings contribute to better understand N-induced effects on allometric relationships of terrestrial plants,and suggest that these ecophysiological responses should be incorporated into models that aim to predict how terrestrial ecosystems may respond to enhanced N deposition under future global change scenarios.展开更多
Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus ...Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity--a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance;. FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching pla- teaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial "human footprint" on behavior may be useful for understanding how human activities affect wildlife展开更多
Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy ...Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy and sandy matters, and the adsorption-desorption capacity of sediment with phosphorus depends on particle size. According to phosphorus adsorption-desorption experiments, phosphorus sorption capacity of the sediment decreases with the increase of particle dimension. But among the size-similar particles, sediment with a bigger particle size has the larger initial phosphorus release rate. In terms of muddy and sandy sediments, there are inversely proportional relationships between the release rate and the flux. Due to the contact of surface sediment and the overlying water, the release flux from the sediment is either from direct desorption of surface sediment layer or from the diffusion of pore water in the sediment layer, which is mainly determined by sediment particle size and porosity. Generally, static phosphorus release process may include two stages: the first is the initial release. As for coarse particles, phosphorus is desorbed from surface sediment. And for fine particles, phosphorus concentration in water often decreases, mainly from pore water by the molecular diffusion. During the second stage, pore water flows faster in coarse sediment, and phosphorus is easy to desorb from the surface of the particles as diffusion dominates. For the smaller liquid-solid ratio of fine particles and the larger amount of phosphorus adsorption, the release flux from pore water due to diffusion is very small with longer sorption duration.展开更多
基金Under the auspices of International Partnership Program of Chinese Academy of Sciences (No.KZCX2-YW-T06)Key Direction in Knowledge Innovation Programs of Chinese Academy of Sciences (No.KZCX2-YW-444)Major State Basic Research Development Program of China (No.2009CB421101)
文摘Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,species physiological response and distribution can be correlated positively or negatively.The consistency of such correlation relationships at different spatial scales determines whether species responses derived from local scales can be extrapo-lated to broader spatial scales.In this study,we used a coupled modeling approach that coupled a plot-level ecosystem process model (LINKAGES) with a spatially explicit landscape model (LANDIS).We investigated species physio-logical responses and distribution responses to climate warming at the local,zonal and landscape scales respectively,and examined how species physiological response and distribution correlated at each corresponding scale and whether the correlations were consistent among these scales.The results indicate that for zonal and warming-sensitive species,the correlations between species physiological response and distribution are consistent at these spatial scales,and therefore the research results of vegetation response to climate warming at the local scale can be extrapolated to the zonal and landscape scales.By contrast,for zonal and warming-insensitive species the correlations among different spatial scales are consistent at some spatial scales but at other scales.The results also suggest that the results of azonal species at the local scale near their distribution boundaries can not be extrapolated simply to broader scales due to stronger responses to climate warming in those boundary regions.
基金supported by the Fundamental Research Funds for the Central Universities(2022BLRD004 and BH2022-03)。
文摘The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland plant biomass from 1980 to 2021.By examining 1134 observations from 182 published papers on wetland ecosystems,we created a comprehensive database of wetland plant above-ground biomass(AGB)and below-ground biomass(BGB).Using this database,we analyzed the biomass characteristics of different climate zones,wetland types and plant species globally.Based on this,we analyzed the differences between the biomass of different plant species and the linkage between AGB and BGB and organic carbon.Our study has revealed that wetland plant AGB is greater in equatorial regions but BGB is highest in polar areas,and lowest in arid and equatorial zones.For plant species,the BGB of the Poales is higher than the AGB but Caryophyllales,Cyperales and Lamiales have higher AGB.Moreover,our findings indicate that BGB plays a more significant role in contributing to the organic carbon pool compared to AGB.Notably,when BGB is less than 1 t C ha^(-1),even slight changes in biomass can have a significant impact on the organic carbon pool.And we observed that the SOC increases by 5.7 t C ha^(-1)when the BGB content is low,indicating that the SOC is more sensitive to changes in biomass under such circumstances.Our study provides a basis for the global response of AGB and BGB of wetland plants to organic carbon.
基金This research was supported by GDAS’(Guangdong Academy of Sciences)Special Project of Science and Technology Development(2020GDASYL-20200301003,2017GDASCX-0805,2020GDASYL-040101,2020GDASYL-20200102001)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA13020506)+1 种基金Science and Technology Projects of Guangdong Province(2017A020216022,2018B030324002)the National Natural Science Foundation of China(31770473).
文摘Aims Unmanned aerial vehicles(UAVs),i.e.drones,have recently emerged as cost-effective and flexible tools for acquiring remote sensing data with fine spatial and temporal resolution.It provides a new method and opportunity for plant ecologists to study issues from individual to regional scales.However,as a new method,UAVs remote sensing applications in plant ecology are still challenged.The needs of plant ecology research and the application development of UAVs remote sensing should be better integrated.Methods This report provides a comprehensive review of UAV-based remote sensing applications in plant ecology to synthesize prospects of applying drones to advance plant ecology research.Important Findings Of the 400 references,59%were published in remote sensing journals rather than in plant ecology journals,reflecting a substantial gap between the interests of remote sensing experts and plant ecologists.Most of the studies focused on UAV remote sensing’s technical aspects,such as data processing and remote sensing inversion,with little attention on answering ecological questions.There were 61%of studies involved community-scale research.RGB and multispectral cameras were the most used sensors(75%).More ecologically meaningful parameters can be extracted from UAV data to better understand the canopy surface irregularity and community heterogeneity,identify geometrical characteristics of canopy gaps and construct canopy chemical assemblies from living vegetation volumes.More cooperation between plant ecologists and remote sensing experts is needed to promote UAV remote sensing in advancing plant ecology research.
基金The International Cooperation Projects of Shenzhen Science and Technology Innovation Committee of China(GJHZ20190822173805220)The International Science and Technology Cooperation Platform Construction Project from China Association for Science and Technology(2021ZZGJB071545).
文摘Urban biodiversity is now recognized as playing a critical role in supporting global biodiversity.However,it is important to note that biodiversity is a systematic and holistic concept and prior studies have not generally focused on cross-border or multi-scale management problems.On one hand,the ecosystems of cities are interconnected with adjacent cities by natural landscapes,so they are like mosaics instead of being isolated.Urban biodiversity research demands the consideration of the continuity within an ecosystem.On the other hand,both active protection and passive restoration strategies for urban biodiversity should not only be developed by researchers or municipal government agencies,but more importantly,they should consider the real ecosystem management problems faced by multi-scale departments in order to build a practicable Pressure-State-Response(PSR)model.The solutions for these issues should be included in the analysis to form a complete and more effective urban biodiversity strategy.The study in this paper offers an answer to whether different scales of cities or districts should adopt the same biodiversity strategy;and therefore,the decision depends on whether the places are of the same importance to the global or regional ecosystem,or whether the ecological elements are connected to the adjacent cities/districts and the problems that multiple stakeholders care about.
基金This research was financially supported by the National Natural Science Foundation of China(31922052,31800373,32022056 and 31800521).
文摘Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments;yet,it remains poorly understood how patterns of biomass allocation respond to nitrogen(N)additions across terrestrial ecosystems worldwide.Methods We conducted a meta-analysis using 5474 pairwise observations from 333 articles to assess how N addition affected plant biomass and biomass allocation among different organs.We also tested the'ratio-based optimal partitioning'vs.the'isometric allocation,hypotheses to explain potential N addition effects on biomass allocation.Important Findings We found that(i)N addition significantly increased whole plant biomass and the biomass of different organs,but decreased rootrshoot ratio(RS)and root mass fraction(RMF)while no effects of N addition on leaf mass fraction and stem mass fraction at the global scale;(ii)the effects of N addition on ratio-based biomass allocation were mediated by individual or interactive effects of moderator variables such as experimental conditions,plant functional types,latitudes and rates of N addition and(iii)N addition did not affect allometric relationships among different organs,suggesting that decreases in RS and RMF may result from isometric allocation patterns following increases in whole plant biomass.Despite alteration of ratio-based biomass allocation between root and shoot by N addition,the unaffected allometric scaling relationships among different organs(including root vs.shoot)suggest that plant biomass allocation patterns are more appropriately explained by the isometric allocation hypothesis rather than the optimal partitioning hypothesis.Our findings contribute to better understand N-induced effects on allometric relationships of terrestrial plants,and suggest that these ecophysiological responses should be incorporated into models that aim to predict how terrestrial ecosystems may respond to enhanced N deposition under future global change scenarios.
文摘Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity--a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance;. FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching pla- teaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial "human footprint" on behavior may be useful for understanding how human activities affect wildlife
基金supported by the National Natural Science Foundation of China(Grant No.10972134)the State Key Program of National Natural Science of China(Grant No.11032007)The Shanghai Program for Innovative Research Team in Universities is also acknowledged
文摘Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy and sandy matters, and the adsorption-desorption capacity of sediment with phosphorus depends on particle size. According to phosphorus adsorption-desorption experiments, phosphorus sorption capacity of the sediment decreases with the increase of particle dimension. But among the size-similar particles, sediment with a bigger particle size has the larger initial phosphorus release rate. In terms of muddy and sandy sediments, there are inversely proportional relationships between the release rate and the flux. Due to the contact of surface sediment and the overlying water, the release flux from the sediment is either from direct desorption of surface sediment layer or from the diffusion of pore water in the sediment layer, which is mainly determined by sediment particle size and porosity. Generally, static phosphorus release process may include two stages: the first is the initial release. As for coarse particles, phosphorus is desorbed from surface sediment. And for fine particles, phosphorus concentration in water often decreases, mainly from pore water by the molecular diffusion. During the second stage, pore water flows faster in coarse sediment, and phosphorus is easy to desorb from the surface of the particles as diffusion dominates. For the smaller liquid-solid ratio of fine particles and the larger amount of phosphorus adsorption, the release flux from pore water due to diffusion is very small with longer sorption duration.