As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laborato...As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laboratories to investigate biodiversity responses to fragmentation.One of these most iconic landscapes is the Balbina Hydroelectric Reservoir in Brazilian Amazonia,occupying>400000 ha and comprising>3500 forest islands.Here,we synthesise the current knowledge on responses of a wide range of biological groups to insular fragmentation at Balbina.Sampling has largely concentrated on a set of 22 islands and three mainland sites.In total,39 studies were conducted over nearly two decades,covering 17 vertebrate,invertebrate,and plant taxa.Although species responses varied according to taxonomic group,island area was consistently included and played a pivotal role in 66.7%of all studies examining patterns of species diversity.Species persistence was further affected by species traits,mostly related to species capacity to use/traverse the aquatic matrix or tolerate habitat degradation,as noted for species of vertebrates and orchid bees.Further research is needed to improve our understanding of such effects on wider ecosystem functioning.Environmental Impact Assessments must account for changes in both the remaining habitat amount and configuration,and subsequent long-term species losses.展开更多
The Arrhenius law implies that reaction rate is a continuous function of temperature.However,the steady laminar flamelet model(SLFM)does not explicitly give this functional relationship.The present study addresses thi...The Arrhenius law implies that reaction rate is a continuous function of temperature.However,the steady laminar flamelet model(SLFM)does not explicitly give this functional relationship.The present study addresses this relation in the SLFM.It is found that reaction rate is not continuous in the mixture-fraction space.As a result,the SLFM is unable to predict local extinction and reignition.Furthermore,we use the unstable branch of the'S-curve'to fill the gap between steady burning branch and extinction one,and find that this modification leads to a continuous dependent of reaction rate on temperature.Thus the modified SLFM can describe the local extinction and reignition.展开更多
Soil ecosystems are far more functionally valuable than previously thought,but soil animals are less visible and often overlooked.Here,we surveyed population sizes of different animal orders in both urban and rural Be...Soil ecosystems are far more functionally valuable than previously thought,but soil animals are less visible and often overlooked.Here,we surveyed population sizes of different animal orders in both urban and rural Beijing from 2013 to 2016,to study the impact of increasing urbanization on the ecology of soil fauna.We found 10 orders had less than 1%of soil-animal population in both urban and rural areas.Populations of 6 orders in urban areas were far smaller than those in rural areas.Between 2013 and 2016,both urban and rural areas had experienced a substantial long-term population decrease,and soil animals in Beijing suffered a 52.8%loss of population.Our study indicates 45.5%of orders may be in danger of local extinction,and 27.3%of orders seem highly susceptible to urbanization.Over just four years the soil-animal population in Beijing is shrinking fast thanks largely to increasing urbanization.This raises the worrying prospect of a future soil fauna that may be at risk of local extinction in cities.It is therefore necessary to provide a pragmatic approach to soil-animal diversity conservation.Moreover,the deeper understanding of soil extinction ecology opens up an exciting frontier of opportunities for future research.展开更多
We simply call a superprocess conditioned on non-extinction a conditioned superprocess. In this study, we investigate some properties of the conditioned superprocesses (subcritical or critical). Firstly, we give an eq...We simply call a superprocess conditioned on non-extinction a conditioned superprocess. In this study, we investigate some properties of the conditioned superprocesses (subcritical or critical). Firstly, we give an equivalent description of the probability of the event that the total occupation time measure on a compact set is finite and some applications of this equivalent description. Our results are extensions of those of Krone (1995) from particular branching mechanisms to general branching mechanisms. We also prove a claim of Krone for the cases of d = 3, 4. Secondly, we study the local extinction property of the conditioned binary super-Brownian motion {X t , P μ ∞ }. When d = 1, as t goes to infinity, X t / $ \sqrt t $ converges to ηλ in weak sense under P μ ∞ , where η is a nonnegative random variable and λ is the Lebesgue measure on ?. When d ? 2, the conditioned binary super-Brownian motion is locally extinct under P μ ∞ .展开更多
Background Temperature,as one of the effective environmental stimuli in many aspects of species life and ecosystems,can affect amphibians in many ways.Knowing and predicting temperature change and its possible effects...Background Temperature,as one of the effective environmental stimuli in many aspects of species life and ecosystems,can affect amphibians in many ways.Knowing and predicting temperature change and its possible effects on the habitat suitability and movements of amphibians have led many researchers to use climate change scenarios and species distribution models(SDMs).One of the important remote-sensing products that received less attention of conservation biologists is the land surface temperature(LST).Due to the small difference between LST and air temperature,this component can be used to investigate and monitor the daily and seasonal changes of habitats.This study aims to investigate the seasonal trend of LST in the habitat suitability and connectivity of the critically endangered newt(Neurergus derjugini)in its small distribution range,using the MODIS LST time series(2003 to 2021)and with the help of SDMs,Mann–Kendall(MK)and Pettitt non-parametric tests.Results In the last decade,the increasing trend of LST versus its decreasing trends is obvious.Based on MK and Pettitt tests,in the winter and spring,with the decrease in latitude of 35.45°and increase in longitude of 46.14°,the core populations which are located in the southeast have experienced an increase in temperature.Considering the period time of breeding and overwintering,the continuity of winter and spring can be effective on the survival of adult newts as well as larvae in the microclimate.Linkages with the highest current flow between core populations in the winter and summer are the most likely to be vulnerable.At the level of habitat,the increase in LST is proportional to the trend of thermal landscape changes,and all seasons have had an increase in LST,but in winter and summer,the largest area of the habitat has been involved.By continuing the current trend,many high-altitude southern habitats in Iran will be endangered,and the species will be at risk of local extinction.Conclusion The increasing trend of temperature in all seasons such as winter will affect many adaptations of the species and these effects are mostly evident in the southern parts of its distribution range therefore,captive breeding and reintroduction are recommended for the populations of these areas.展开更多
基金supported byÁreas Protegidas da Amazônia(ARPA)Amazonas Distribuidora de Energia S.A.,and Associação Comunidade Waimiri Atroari+4 种基金Rufford Foundation(grant number 13675-1)the Conservation Food and Health Foundation,and Idea WildNational Geographic Society grant(NGS-93497C-22)awarded to CAP.I.J is funded through a UKRI Future Leaders Fellowship(MR/T019018/1)M.B received a productivity grant from CNPq(304189/2022-7)European Union’s Horizon 2020 research and innovation programme under the grant agreement No.854248(TROPIBIO)。
文摘As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laboratories to investigate biodiversity responses to fragmentation.One of these most iconic landscapes is the Balbina Hydroelectric Reservoir in Brazilian Amazonia,occupying>400000 ha and comprising>3500 forest islands.Here,we synthesise the current knowledge on responses of a wide range of biological groups to insular fragmentation at Balbina.Sampling has largely concentrated on a set of 22 islands and three mainland sites.In total,39 studies were conducted over nearly two decades,covering 17 vertebrate,invertebrate,and plant taxa.Although species responses varied according to taxonomic group,island area was consistently included and played a pivotal role in 66.7%of all studies examining patterns of species diversity.Species persistence was further affected by species traits,mostly related to species capacity to use/traverse the aquatic matrix or tolerate habitat degradation,as noted for species of vertebrates and orchid bees.Further research is needed to improve our understanding of such effects on wider ecosystem functioning.Environmental Impact Assessments must account for changes in both the remaining habitat amount and configuration,and subsequent long-term species losses.
基金supported by CAS(KJCX2-SW-L08),973 Program of China(2007CB814800,2009CB724100)NSFC(11072247,10702074,10732090,50906096)the LNM initial funding for young investigators
文摘The Arrhenius law implies that reaction rate is a continuous function of temperature.However,the steady laminar flamelet model(SLFM)does not explicitly give this functional relationship.The present study addresses this relation in the SLFM.It is found that reaction rate is not continuous in the mixture-fraction space.As a result,the SLFM is unable to predict local extinction and reignition.Furthermore,we use the unstable branch of the'S-curve'to fill the gap between steady burning branch and extinction one,and find that this modification leads to a continuous dependent of reaction rate on temperature.Thus the modified SLFM can describe the local extinction and reignition.
基金This research was supported by National Science&Technology Fundamental Resources Investigation Program of China(Grant No.2019FY100400).
文摘Soil ecosystems are far more functionally valuable than previously thought,but soil animals are less visible and often overlooked.Here,we surveyed population sizes of different animal orders in both urban and rural Beijing from 2013 to 2016,to study the impact of increasing urbanization on the ecology of soil fauna.We found 10 orders had less than 1%of soil-animal population in both urban and rural areas.Populations of 6 orders in urban areas were far smaller than those in rural areas.Between 2013 and 2016,both urban and rural areas had experienced a substantial long-term population decrease,and soil animals in Beijing suffered a 52.8%loss of population.Our study indicates 45.5%of orders may be in danger of local extinction,and 27.3%of orders seem highly susceptible to urbanization.Over just four years the soil-animal population in Beijing is shrinking fast thanks largely to increasing urbanization.This raises the worrying prospect of a future soil fauna that may be at risk of local extinction in cities.It is therefore necessary to provide a pragmatic approach to soil-animal diversity conservation.Moreover,the deeper understanding of soil extinction ecology opens up an exciting frontier of opportunities for future research.
基金supported by National Natural Science Foundation of China (Grant No. 10471003, 10871103)
文摘We simply call a superprocess conditioned on non-extinction a conditioned superprocess. In this study, we investigate some properties of the conditioned superprocesses (subcritical or critical). Firstly, we give an equivalent description of the probability of the event that the total occupation time measure on a compact set is finite and some applications of this equivalent description. Our results are extensions of those of Krone (1995) from particular branching mechanisms to general branching mechanisms. We also prove a claim of Krone for the cases of d = 3, 4. Secondly, we study the local extinction property of the conditioned binary super-Brownian motion {X t , P μ ∞ }. When d = 1, as t goes to infinity, X t / $ \sqrt t $ converges to ηλ in weak sense under P μ ∞ , where η is a nonnegative random variable and λ is the Lebesgue measure on ?. When d ? 2, the conditioned binary super-Brownian motion is locally extinct under P μ ∞ .
文摘Background Temperature,as one of the effective environmental stimuli in many aspects of species life and ecosystems,can affect amphibians in many ways.Knowing and predicting temperature change and its possible effects on the habitat suitability and movements of amphibians have led many researchers to use climate change scenarios and species distribution models(SDMs).One of the important remote-sensing products that received less attention of conservation biologists is the land surface temperature(LST).Due to the small difference between LST and air temperature,this component can be used to investigate and monitor the daily and seasonal changes of habitats.This study aims to investigate the seasonal trend of LST in the habitat suitability and connectivity of the critically endangered newt(Neurergus derjugini)in its small distribution range,using the MODIS LST time series(2003 to 2021)and with the help of SDMs,Mann–Kendall(MK)and Pettitt non-parametric tests.Results In the last decade,the increasing trend of LST versus its decreasing trends is obvious.Based on MK and Pettitt tests,in the winter and spring,with the decrease in latitude of 35.45°and increase in longitude of 46.14°,the core populations which are located in the southeast have experienced an increase in temperature.Considering the period time of breeding and overwintering,the continuity of winter and spring can be effective on the survival of adult newts as well as larvae in the microclimate.Linkages with the highest current flow between core populations in the winter and summer are the most likely to be vulnerable.At the level of habitat,the increase in LST is proportional to the trend of thermal landscape changes,and all seasons have had an increase in LST,but in winter and summer,the largest area of the habitat has been involved.By continuing the current trend,many high-altitude southern habitats in Iran will be endangered,and the species will be at risk of local extinction.Conclusion The increasing trend of temperature in all seasons such as winter will affect many adaptations of the species and these effects are mostly evident in the southern parts of its distribution range therefore,captive breeding and reintroduction are recommended for the populations of these areas.
