A robust ecological security network(ESN)is essential for ensuring regional ecological security,improving fragile ecological conditions,and promoting sustainable development.Climate change and land use/cover change(LU...A robust ecological security network(ESN)is essential for ensuring regional ecological security,improving fragile ecological conditions,and promoting sustainable development.Climate change and land use/cover change(LUCC)influence the structure and connectivity of the ESN by impacting ecosystem services(ESs).Previous studies primarily focused on the overall effects of LUCC on ESN changes,but they largely overlooked the effects of detailed LUCC transitions.In this study,we evaluated changes in the structure and connectivity of the ESN in the Songnen Plain(SNP),Northeast China,over the past 30 yr(1990s-2020s)using circuit theory and graph theory.We further explored the effects of climate change,LUCC,and detailed LUCC transformations on ESN changes through factorial control experiments.Results revealed a 24.86%decrease in ecological sources and a 27.06%decrease in ecological corridors,accompanied by a decline in ESN connectivity from the 1990s to the 2010s.Conversely,from the 2010s to the 2020s,ecological sources increased by 14.71%and ecological corridors increased by 25.71%due to ecological projects such as returning farmland to wetlands,resulting in an overall increase in ESN connectivity.The changes in ESN structure were primarily attributed to LUCC effects,followed by climate change effects and their interactions.In contrast,the changes in connectivity were significantly affected by climate change,followed by interactive effects and LUCC.Through detailed examination of LUCC transformation effects,we further found that the changes in ESN structure were primarily attributed to wetland loss,followed by deforestation and urban expansion.Meanwhile,the changes in ESN connectivity were mainly due to the effects of wetland loss,urban expansion and deforestation.Notably,the adverse effects of wetland loss partly offset climate change benefits on ESN.Our study offers valuable insights for developing future land management policies and implementing ecological projects,aimed at maintaining a stable ESN and ensuring sustainable human development.展开更多
The increasing frequency of recent droughts has an adverse effect on the ecosystem of the Mongolian Plateau.The growth condition of NPP is considered an indicator of the ecological function.Therefore,identifying the r...The increasing frequency of recent droughts has an adverse effect on the ecosystem of the Mongolian Plateau.The growth condition of NPP is considered an indicator of the ecological function.Therefore,identifying the relationship between NPP and drought can assist in the prevention of drought-associated disasters and the conservation of the ecological environment of the Mongolian Plateau.This study used the Carnegie-Ames-Stanford Approach(CASA)model to simulate the NPP capacity of the Mongolian Plateau between 1982 and 2015,as well as drought indicators(drought probability,vulnerability,and risk)to explore the drought risk of NPP.The findings pointed to an overall increase in NPP with regional variances;however,the NPP rate in Inner Mongolia was considerably higher than that in Mongolia.The standardized precipitation evapotranspiration index(SPEI)showed an overall downward trend,with Inner Mongolia experiencing a substantially lower rate of decline than Mongolia.The areas most likely to experience drought were primarily in the center and north while the areas with the highest drought vulnerability were primarily in the northeast,center,and southeast.Mongolia showed a higher probability of drought compared to Inner Mongolia.Drought-prone regions of the Mongolian Plateau increased during the 21st century while drought-vulnerable areas increased and shifted from north to south.Alpine grasslands and coniferous forests were least vulnerable to drought,while other vegetation types experienced temporal variation.In the 21st century,the primary determinants of drought risk shifted from precipitation and the normalized difference vegetation index(NDVI)to temperature and relative humidity.展开更多
基金Under the auspices of National Key Research and Development Program of China(No.2022YFF1300904)the National Natural Science Foundation of China(No.42271119,42371075,42471127)+1 种基金Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2023238)Jilin Province Science and Technology Development Plan Project(No.20230203001SF)。
文摘A robust ecological security network(ESN)is essential for ensuring regional ecological security,improving fragile ecological conditions,and promoting sustainable development.Climate change and land use/cover change(LUCC)influence the structure and connectivity of the ESN by impacting ecosystem services(ESs).Previous studies primarily focused on the overall effects of LUCC on ESN changes,but they largely overlooked the effects of detailed LUCC transitions.In this study,we evaluated changes in the structure and connectivity of the ESN in the Songnen Plain(SNP),Northeast China,over the past 30 yr(1990s-2020s)using circuit theory and graph theory.We further explored the effects of climate change,LUCC,and detailed LUCC transformations on ESN changes through factorial control experiments.Results revealed a 24.86%decrease in ecological sources and a 27.06%decrease in ecological corridors,accompanied by a decline in ESN connectivity from the 1990s to the 2010s.Conversely,from the 2010s to the 2020s,ecological sources increased by 14.71%and ecological corridors increased by 25.71%due to ecological projects such as returning farmland to wetlands,resulting in an overall increase in ESN connectivity.The changes in ESN structure were primarily attributed to LUCC effects,followed by climate change effects and their interactions.In contrast,the changes in connectivity were significantly affected by climate change,followed by interactive effects and LUCC.Through detailed examination of LUCC transformation effects,we further found that the changes in ESN structure were primarily attributed to wetland loss,followed by deforestation and urban expansion.Meanwhile,the changes in ESN connectivity were mainly due to the effects of wetland loss,urban expansion and deforestation.Notably,the adverse effects of wetland loss partly offset climate change benefits on ESN.Our study offers valuable insights for developing future land management policies and implementing ecological projects,aimed at maintaining a stable ESN and ensuring sustainable human development.
基金Natural Science Foundation of Inner Mongolia,No.2023MS04001National Natural Science Foundation of China,No.42061070,No.42261144746+2 种基金Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region,No.NJYT23018Innovative Project of Young“Grasslands Talents”Fundamental Research Funds for the Inner Mongolia Normal University,No.2022JBBJ013,No.2022JBTD011。
文摘The increasing frequency of recent droughts has an adverse effect on the ecosystem of the Mongolian Plateau.The growth condition of NPP is considered an indicator of the ecological function.Therefore,identifying the relationship between NPP and drought can assist in the prevention of drought-associated disasters and the conservation of the ecological environment of the Mongolian Plateau.This study used the Carnegie-Ames-Stanford Approach(CASA)model to simulate the NPP capacity of the Mongolian Plateau between 1982 and 2015,as well as drought indicators(drought probability,vulnerability,and risk)to explore the drought risk of NPP.The findings pointed to an overall increase in NPP with regional variances;however,the NPP rate in Inner Mongolia was considerably higher than that in Mongolia.The standardized precipitation evapotranspiration index(SPEI)showed an overall downward trend,with Inner Mongolia experiencing a substantially lower rate of decline than Mongolia.The areas most likely to experience drought were primarily in the center and north while the areas with the highest drought vulnerability were primarily in the northeast,center,and southeast.Mongolia showed a higher probability of drought compared to Inner Mongolia.Drought-prone regions of the Mongolian Plateau increased during the 21st century while drought-vulnerable areas increased and shifted from north to south.Alpine grasslands and coniferous forests were least vulnerable to drought,while other vegetation types experienced temporal variation.In the 21st century,the primary determinants of drought risk shifted from precipitation and the normalized difference vegetation index(NDVI)to temperature and relative humidity.
