In this paper,we study the asymptotic dynamics of a single-species model with resource-dependent dispersal in one dimension.To overcome the analytical difficulties brought by the resource-dependent dispersal,we use th...In this paper,we study the asymptotic dynamics of a single-species model with resource-dependent dispersal in one dimension.To overcome the analytical difficulties brought by the resource-dependent dispersal,we use the idea of changing variables to transform the model into a uniform dispersal one.Then the existence and uniqueness of positive stationary solution to the model can be verified by the squeezing argument,where the solution plays a crucial role in later analyses.Moreover,the asymptotic behavior of solutions to the model is obtained by the upper-lower solutions method.The result indicates that the solutions of the model converge to the corresponding positive stationary solution locally uniformly in one dimension as time goes to infinity.展开更多
Resource-dependent cities(RCs)are a vulnerable group of urban settlements that often face population shrinkage;however,population changes in RCs in China are not well understood.This study offers new insight into this...Resource-dependent cities(RCs)are a vulnerable group of urban settlements that often face population shrinkage;however,population changes in RCs in China are not well understood.This study offers new insight into this matter through a robust analysis that features a longer time scale,a larger sample of RCs,and a finer unit of analysis.It finds new evidence that problems of population shrinkage in RCs are more serious than previous literature has suggested.Approximately 30%of the studied units have experienced either long-term or short-term population shrinkage,and many more are experiencing a slowing down of population growth.Problems are especially common among three types of RCs:the resource-depleted RCs,the forestry-based RCs,and RCs in Northeast China.These results underscore transition policy inadequacies in addressing population loss,and call for a more comprehensive and diversified population policy that tackles the multifaceted factors that contribute to population shrinkage,including lack of industrial support,maladjustment to market oriented reformation,poor urban environment and natural population decline.展开更多
Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping ene...Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping energy security has gained significant attention in recent years.Natural resources and geopolitical risk are examined in 38 countries at risk of geopolitical conflict between 1990 and 2021 by examining CO_(2) emissions,renewable energy consumption,and foreign direct investment as controlling variables.The long-run analysis conducted in this study focused on slope heterogeneity,Westerlund cointegration,and dynamic panel data estimation.The findings indicated that the energy security index is positively associated with various determinants,including natural resources,geopolitical risk,CO_(2) emissions,and renewable energy consumption.However,foreign direct investment was found to be negatively associated with the energy security index among the selected 38 geopolitical risk countries.The role of natural resources and geopolitical risk in energy security cannot be overlooked.Natural resources provide the raw materials for generating electricity and powering our societies,while geopolitical risks can disrupt energy supply chains and threaten stability.Achieving sustainable energy security requires a comprehensive approach that addresses both aspects of energy provision.Transitioning to renewable energy sources,improving energy efficiency,diversifying energy supplies,promoting international cooperation,and conserving natural resources are essential steps towards a more sustainable and resilient energy future.展开更多
Resource-dependent cities are cities whose economic development depends on the exploitation and processing of natural resources.Their transformation and sustainable development are an important area of research on reg...Resource-dependent cities are cities whose economic development depends on the exploitation and processing of natural resources.Their transformation and sustainable development are an important area of research on regional industrial development,regional economy and urban development.Since the Chinese government launched a pilot project to transform resource-dependent cities,starting with Fuxin in Liaoning Province in 2001,accurately identifying and classifying China’s resource-dependent cities has become a focus of geographical research.Based on previous studies,this paper uses the theory and methods of urban function classification to analyze indicators and threshold values for identifying and classifying resource-dependent cities.It has thus identified 262 cities as being resource-dependent.Looking at the development levels,problems,characteristics and developmental direction of such cities,this paper attempts to establish a comprehensive analytical framework using the two evaluation indicators of resource security and sustainable development.It also creates a model to classify the 262 cities identified as resource-dependent cities into four types:growing cities,mature cities,declining cities and regenerating cities.The different connotations and characteristics of the city types were then analyzed.The results of this research support the delineation of scopes and categories of resource-dependent cities set out in the National Sustainable Development Plan for Resource-Dependent Cities published by the State Council,and they serve as a foundation for formulating policies on planning,classification and guidance.展开更多
基金supported by the National Natural Science Foundation of China (Nos.12301101,12101121)the Guangdong Basic and Applied Basic Research Foundation (Nos.2022A1515110019,2020A1515110585)。
文摘In this paper,we study the asymptotic dynamics of a single-species model with resource-dependent dispersal in one dimension.To overcome the analytical difficulties brought by the resource-dependent dispersal,we use the idea of changing variables to transform the model into a uniform dispersal one.Then the existence and uniqueness of positive stationary solution to the model can be verified by the squeezing argument,where the solution plays a crucial role in later analyses.Moreover,the asymptotic behavior of solutions to the model is obtained by the upper-lower solutions method.The result indicates that the solutions of the model converge to the corresponding positive stationary solution locally uniformly in one dimension as time goes to infinity.
基金Under the auspices of Key Research Program of the Chinese Academy of Sciences(No.ZDRW-ZS-2017-4-3-4)National Science and Technology Basic Project of the Ministry of Science and Technology of China(No.2017FY101303-1)+1 种基金National Natural Science Foundation of China(No.41001097,41571152)Liaoning Revitalization Talents Program(No.XLYC1807249)
文摘Resource-dependent cities(RCs)are a vulnerable group of urban settlements that often face population shrinkage;however,population changes in RCs in China are not well understood.This study offers new insight into this matter through a robust analysis that features a longer time scale,a larger sample of RCs,and a finer unit of analysis.It finds new evidence that problems of population shrinkage in RCs are more serious than previous literature has suggested.Approximately 30%of the studied units have experienced either long-term or short-term population shrinkage,and many more are experiencing a slowing down of population growth.Problems are especially common among three types of RCs:the resource-depleted RCs,the forestry-based RCs,and RCs in Northeast China.These results underscore transition policy inadequacies in addressing population loss,and call for a more comprehensive and diversified population policy that tackles the multifaceted factors that contribute to population shrinkage,including lack of industrial support,maladjustment to market oriented reformation,poor urban environment and natural population decline.
基金funded by a grant from the Interdisciplinary Research Institute in New Finance and Economics,Hubei University of Economics(No.JXZD202403).
文摘Energy security is a crucial aspect of modern societies,as it directly impacts the availability,accessibility,and reliability of energy sources.The reliance on natural resources and geopolitical factors in shaping energy security has gained significant attention in recent years.Natural resources and geopolitical risk are examined in 38 countries at risk of geopolitical conflict between 1990 and 2021 by examining CO_(2) emissions,renewable energy consumption,and foreign direct investment as controlling variables.The long-run analysis conducted in this study focused on slope heterogeneity,Westerlund cointegration,and dynamic panel data estimation.The findings indicated that the energy security index is positively associated with various determinants,including natural resources,geopolitical risk,CO_(2) emissions,and renewable energy consumption.However,foreign direct investment was found to be negatively associated with the energy security index among the selected 38 geopolitical risk countries.The role of natural resources and geopolitical risk in energy security cannot be overlooked.Natural resources provide the raw materials for generating electricity and powering our societies,while geopolitical risks can disrupt energy supply chains and threaten stability.Achieving sustainable energy security requires a comprehensive approach that addresses both aspects of energy provision.Transitioning to renewable energy sources,improving energy efficiency,diversifying energy supplies,promoting international cooperation,and conserving natural resources are essential steps towards a more sustainable and resilient energy future.
基金National Natural Science Foundation of China,No.41671166,No.41701128
文摘Resource-dependent cities are cities whose economic development depends on the exploitation and processing of natural resources.Their transformation and sustainable development are an important area of research on regional industrial development,regional economy and urban development.Since the Chinese government launched a pilot project to transform resource-dependent cities,starting with Fuxin in Liaoning Province in 2001,accurately identifying and classifying China’s resource-dependent cities has become a focus of geographical research.Based on previous studies,this paper uses the theory and methods of urban function classification to analyze indicators and threshold values for identifying and classifying resource-dependent cities.It has thus identified 262 cities as being resource-dependent.Looking at the development levels,problems,characteristics and developmental direction of such cities,this paper attempts to establish a comprehensive analytical framework using the two evaluation indicators of resource security and sustainable development.It also creates a model to classify the 262 cities identified as resource-dependent cities into four types:growing cities,mature cities,declining cities and regenerating cities.The different connotations and characteristics of the city types were then analyzed.The results of this research support the delineation of scopes and categories of resource-dependent cities set out in the National Sustainable Development Plan for Resource-Dependent Cities published by the State Council,and they serve as a foundation for formulating policies on planning,classification and guidance.
