Northern Xinjiang,an arid inland area in Northwest China,is highly vulnerable to air pollution under intensifying climate extremes,yet the relative roles of temperature and precipitation extremes remain insufficiently...Northern Xinjiang,an arid inland area in Northwest China,is highly vulnerable to air pollution under intensifying climate extremes,yet the relative roles of temperature and precipitation extremes remain insufficiently understood.Using multi-source datasets for 2000-2023,including China High Air Pollutants(CHAP)particulate matter 2.5(PM_(2.5)),particulate matter 10(PM_(10)),and ozone(O3)products and Expert Team on Climate Change Detection and Indices(ETCCDI)extreme climate indices derived from the European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis v5(ERA5)-Land,together with trend detection,change-point analysis,pixel-wise Pearson correlation,and random forest(RF)modeling,we investigated the spatiotemporal evolution of major air pollutants and their responses to meteorological extremes in northern Xinjiang.PM_(2.5) and PM_(10) generally declined from 2000 to 2023,whereas O3 increased,indicating a shift from particulate-dominated pollution toward stronger photochemical pollution.Interannually,PM_(2.5) showed a rise-decline pattern,PM_(10) exhibited a rise-decline-rebound pattern,and O3 increased markedly after 2015.Clear seasonal contrasts were observed,with PM_(2.5) peaking in winter,PM_(10) in spring,and O3 in summer.During the same period,northern Xinjiang exhibited a pronounced warming-drying tendency,characterized by increasing heat-related indices,decreasing cold-related indices,reduced precipitation totals and heavy-rainfall frequency,and increasing consecutive dry days.Pollutant-climate relationships showed strong spatial heterogeneity and pollutant-specific contrasts across the Urumqi-Changji-Shihezi corridor,the Ili River Valley,and the Junggar Basin.PM_(2.5) responses to precipitation shifted from predominantly positive to negative,PM_(10) showed mainly negative associations with precipitation extremes,and O3 responses varied by subregion.Temperature-related extremes generally explained more pollutant variability than precipitation-related extremes,with PM_(2.5) showing the highest sensitivity.These findings highlight the coupled influences of warming,drying,emissions,and terrain-controlled transport on air quality and support region-specific,multi-pollutant strategies for coordinated climate adaptation and air pollution control in northern Xinjiang.展开更多
This paper examines spatio-temporal characteristics of an oasis economy and its relationship with water and mineral resources in the Tarim River Basin from 1965 to 2005. A spatial autocorrelation model, the center of ...This paper examines spatio-temporal characteristics of an oasis economy and its relationship with water and mineral resources in the Tarim River Basin from 1965 to 2005. A spatial autocorrelation model, the center of gravity model, and index system of the regional central city are used to probe the evolution laws of spatial structure of oasis economy. The study finds that: 1) The economic centre of gravity, whose variation track during this period follows linear rate law, was moving from headstream to middle reaches of the Tarim River. 2) Positive spatial autocorrelation which showed a waving and ascending trend of regional economy was significant and the neighbor effect of regional economic growth was strengthened continuously. 3) The regional economic centre was located in Hotan City before 1980, moved to Aksu City during the 1980s and to Korla City after 1990. We conclude that above all, during the recent four decades the evolution of the oasis economy in this region has gone through three stages: a traditional agriculture stage (before 1980), oasis agriculture and agricultural product processing stage (1980–1990) and oasis energy industry stage (after 1990). Furthermore, the dependence degree of the oasis economy on natural resources in different stages are studied by using dominance index, regression model, and grey relation method, which shows that an oasis econ- omy highly depends on water resources in the oasis agriculture and agricultural product processing stage while it de- pends more on mineral resources such as oil and natural gas during the oasis energy industry stage.展开更多
Understanding the spatial interactions among multiple ecosystem services is crucial for ecosystem services management. Ecosystem services, including crop production, freshwater supply, aquatic production, net primary ...Understanding the spatial interactions among multiple ecosystem services is crucial for ecosystem services management. Ecosystem services, including crop production, freshwater supply, aquatic production, net primary production, soil conservation, water conservation, flood regulation, forest recreation, were measured at 1-km grid scale covering the Taihu Lake Basin(TLB) of China. Our objective is to get a comprehensive understanding of the spatial distributions, trade-offs, synergies of multiple ecosystem services across the TLB. Our results found that: 1) majority of ecosystem services were clustered in space and had a similar spatial distribution pattern with the geographical resource endowment. Most of the landscape contributed a high supply of no services, one or two, and a low supply of three to seven services. 2) There were high correlation between forest recreation and freshwater supply and regulating services. Aquatic production had low correlation with other services. 3) The changes of provisioning services led to trade-offs between regulating services and cultural services in the TLB, while synergies mainly occurred among the provisioning service. 4) The spatial relationships of multiple services are consistent at 1-km spatial scale, counties and provinces. This research could help integrate multiple ecosystem services across scales and serve as a reference for decision making.展开更多
The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However,little attention has been paid to the growth process of the emerging metropolitan are...The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However,little attention has been paid to the growth process of the emerging metropolitan area situated in major grain producing locations in the central China.Taking the Zhengzhou metropolitan area(ZZMA)as a case study,we developed an inverse S-shape model to characterize the spatial distribution of urban land density,and constructed an urban expansion core index,urban expansion intensity index,and urban compactness index to quantify the spatial structure change that has taken place from 1978 to 2017 during the process of urban expansion.Moreover,cropland contribution rate(CR)was constructed to evaluate the impacts of urban expansion on croplands.We uncovered four key findings.First,over the past 40 yr,the ZZMA has experienced dramatic expansion,and the central city of Zhengzhou expanded faster than other cities.The gravity centers of urban expansion of surrounding cities were moving toward to Zhengzhou City.Second,the urban land density decreased with the distance from the city center to the outskirts.As the only large city,Zhengzhou has experienced the fastest and most compact centralized urban expansion,especially after 2000,while other medium-and small-sized cities have experienced low-intensity decentralized expansion.Third,the urban core has been gradually expanding outward.From 1978 to 2017,the hot-zone of urban growth has moved progressively with the acceleration of urbanization.All cities except Jiaozuo had a single peak in different periods.Forth,the cities in national core grain-producing areas has higher cropland contribution rates and lower urban expansion areas,which was closely related to cropland protection.Further analysis showed that large city was relatively better positioned than smaller cities in the efficiency of their urban infrastructure and the effectiveness of wealth creation efficiency in the urbanized area could be tested in all cities,and the policy factor seemed to play an important role in the urban expansion process.展开更多
基金supported by the Tianshan Talent Training Program of Xinjiang Uygur Autonomous Region(2022TSYCLJ0011)the Key Research and Development(R&D)Program of Xinjiang Uygur Autonomous Region(2022B03021)the National Key R&D Program of China(2024YFC3713504).
文摘Northern Xinjiang,an arid inland area in Northwest China,is highly vulnerable to air pollution under intensifying climate extremes,yet the relative roles of temperature and precipitation extremes remain insufficiently understood.Using multi-source datasets for 2000-2023,including China High Air Pollutants(CHAP)particulate matter 2.5(PM_(2.5)),particulate matter 10(PM_(10)),and ozone(O3)products and Expert Team on Climate Change Detection and Indices(ETCCDI)extreme climate indices derived from the European Centre for Medium-Range Weather Forecasts(ECMWF)Reanalysis v5(ERA5)-Land,together with trend detection,change-point analysis,pixel-wise Pearson correlation,and random forest(RF)modeling,we investigated the spatiotemporal evolution of major air pollutants and their responses to meteorological extremes in northern Xinjiang.PM_(2.5) and PM_(10) generally declined from 2000 to 2023,whereas O3 increased,indicating a shift from particulate-dominated pollution toward stronger photochemical pollution.Interannually,PM_(2.5) showed a rise-decline pattern,PM_(10) exhibited a rise-decline-rebound pattern,and O3 increased markedly after 2015.Clear seasonal contrasts were observed,with PM_(2.5) peaking in winter,PM_(10) in spring,and O3 in summer.During the same period,northern Xinjiang exhibited a pronounced warming-drying tendency,characterized by increasing heat-related indices,decreasing cold-related indices,reduced precipitation totals and heavy-rainfall frequency,and increasing consecutive dry days.Pollutant-climate relationships showed strong spatial heterogeneity and pollutant-specific contrasts across the Urumqi-Changji-Shihezi corridor,the Ili River Valley,and the Junggar Basin.PM_(2.5) responses to precipitation shifted from predominantly positive to negative,PM_(10) showed mainly negative associations with precipitation extremes,and O3 responses varied by subregion.Temperature-related extremes generally explained more pollutant variability than precipitation-related extremes,with PM_(2.5) showing the highest sensitivity.These findings highlight the coupled influences of warming,drying,emissions,and terrain-controlled transport on air quality and support region-specific,multi-pollutant strategies for coordinated climate adaptation and air pollution control in northern Xinjiang.
基金Under the auspices of Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-XB2-03-03)Western Doctor Plan of Chinese Academy of Sciences
文摘This paper examines spatio-temporal characteristics of an oasis economy and its relationship with water and mineral resources in the Tarim River Basin from 1965 to 2005. A spatial autocorrelation model, the center of gravity model, and index system of the regional central city are used to probe the evolution laws of spatial structure of oasis economy. The study finds that: 1) The economic centre of gravity, whose variation track during this period follows linear rate law, was moving from headstream to middle reaches of the Tarim River. 2) Positive spatial autocorrelation which showed a waving and ascending trend of regional economy was significant and the neighbor effect of regional economic growth was strengthened continuously. 3) The regional economic centre was located in Hotan City before 1980, moved to Aksu City during the 1980s and to Korla City after 1990. We conclude that above all, during the recent four decades the evolution of the oasis economy in this region has gone through three stages: a traditional agriculture stage (before 1980), oasis agriculture and agricultural product processing stage (1980–1990) and oasis energy industry stage (after 1990). Furthermore, the dependence degree of the oasis economy on natural resources in different stages are studied by using dominance index, regression model, and grey relation method, which shows that an oasis econ- omy highly depends on water resources in the oasis agriculture and agricultural product processing stage while it de- pends more on mineral resources such as oil and natural gas during the oasis energy industry stage.
基金Under the auspices of National Social Science Foundation of China(No.14BJY021)National Natural Science Foundation of China(40901296,U1404402)Youth backbone teachers of Henan province’s universities(No.2014GGJS-044)
文摘Understanding the spatial interactions among multiple ecosystem services is crucial for ecosystem services management. Ecosystem services, including crop production, freshwater supply, aquatic production, net primary production, soil conservation, water conservation, flood regulation, forest recreation, were measured at 1-km grid scale covering the Taihu Lake Basin(TLB) of China. Our objective is to get a comprehensive understanding of the spatial distributions, trade-offs, synergies of multiple ecosystem services across the TLB. Our results found that: 1) majority of ecosystem services were clustered in space and had a similar spatial distribution pattern with the geographical resource endowment. Most of the landscape contributed a high supply of no services, one or two, and a low supply of three to seven services. 2) There were high correlation between forest recreation and freshwater supply and regulating services. Aquatic production had low correlation with other services. 3) The changes of provisioning services led to trade-offs between regulating services and cultural services in the TLB, while synergies mainly occurred among the provisioning service. 4) The spatial relationships of multiple services are consistent at 1-km spatial scale, counties and provinces. This research could help integrate multiple ecosystem services across scales and serve as a reference for decision making.
基金Under the auspices of National Natural Science Foundation of China(No.41971274)the Innovation Research Team of Henan Provincial University(No.2021-CXTD-08,2022-CXTD-02)the Scientific and Technological Innovation Team of Universities in Henan Province(No.22IRTSTHN008)。
文摘The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However,little attention has been paid to the growth process of the emerging metropolitan area situated in major grain producing locations in the central China.Taking the Zhengzhou metropolitan area(ZZMA)as a case study,we developed an inverse S-shape model to characterize the spatial distribution of urban land density,and constructed an urban expansion core index,urban expansion intensity index,and urban compactness index to quantify the spatial structure change that has taken place from 1978 to 2017 during the process of urban expansion.Moreover,cropland contribution rate(CR)was constructed to evaluate the impacts of urban expansion on croplands.We uncovered four key findings.First,over the past 40 yr,the ZZMA has experienced dramatic expansion,and the central city of Zhengzhou expanded faster than other cities.The gravity centers of urban expansion of surrounding cities were moving toward to Zhengzhou City.Second,the urban land density decreased with the distance from the city center to the outskirts.As the only large city,Zhengzhou has experienced the fastest and most compact centralized urban expansion,especially after 2000,while other medium-and small-sized cities have experienced low-intensity decentralized expansion.Third,the urban core has been gradually expanding outward.From 1978 to 2017,the hot-zone of urban growth has moved progressively with the acceleration of urbanization.All cities except Jiaozuo had a single peak in different periods.Forth,the cities in national core grain-producing areas has higher cropland contribution rates and lower urban expansion areas,which was closely related to cropland protection.Further analysis showed that large city was relatively better positioned than smaller cities in the efficiency of their urban infrastructure and the effectiveness of wealth creation efficiency in the urbanized area could be tested in all cities,and the policy factor seemed to play an important role in the urban expansion process.
