The Qinghai-Tibet Plateau(QTP)has three main grassland types:alpine meadow,alpine steppe,and alpine desert steppe.In this study,we asked how plant productivity and species diversity vary with altitude,longitude and la...The Qinghai-Tibet Plateau(QTP)has three main grassland types:alpine meadow,alpine steppe,and alpine desert steppe.In this study,we asked how plant productivity and species diversity vary with altitude,longitude and latitude in alpine grasslands of the QTP.We then identified the environmental factors that drive these observed patterns of plant productivity and species diversity.We found that although plant productivity and species diversity varied greatly across large-scale longitudinal and latitudinal gradients,these changes were strongest across the longitudinal gradient.This finding indicates that moisture rather than temperature has the greatest impact on plant productivity and species diversity of the alpine grasslands in the QTP.We also found that besides soil and climate factors,partial pressure of carbon dioxide(pCO_(2))also has significant effects on plant productivity,and barometric pressure and partial pressure of oxygen(pO_(2))also have significant effects on species diversity.Furthermore,the relationship between the biomass of grassland-dominant species and species diversity was affected by the spatial scale at which these factors were studied.Our study provides new insights into the interconnections between plant productivity and species diversity and the major factors that influence alpine grasslands.It also provides a scientific basis for the maintenance of plant diversity and ecosystem functions in hypoxic(low-oxygen)regions.展开更多
The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,t...The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.展开更多
Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis t...Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis to examine the grain size characteristics of major riparian dunes in the typical cold and arid deserts of China.The results indicate that major riparian dunes of deserts in study area can be classified into three types based on their grain size characteristics.The Bartlett test of sphericity and the Kaiser-Meyer-Olkin(KMO)test were also performed,and their significance values were found to be 0.000 and 0.584,respectively.The results of the principal component analysis revealed that the cumulative contribution rate of the total variance reached 85.9%for the two principal components with characteristic roots greater than 1.0.The primary principal component included medium sand,whereas the secondary principal component included fine sand.We conducted a cluster analysis and classified the samples into three major types.Type I rivers include the Keriya River,Langqu River,Tora River and Heihe River,which are characterized by by fine particle size,and well-sorted.Type II includes Mu Bulag River,Kuye River,and the Xar Moron River,Compared with type I,it has a relatively coarser mean grain size and relatively poor sorting for this type.Type III includes the Maquan River,which is characterized mainly by fine sand and medium sand,accounting for more than 90%,and the sorting coefficient(0.52)suggests relatively well sorting in this pattern.Moreover,principal component analysis was applied to determine the particle sizes of samples from different watersheds.Moreover,these sediments exhibit both hydromorphic and aeolian features.At the drainage basin scale,the mode and intensity of aeolian-fluvial interactions depend on climatic conditions.In arid and semi-arid climate regions,wind is the dominant force,and the grain size exhibits significant aeolian features.Conversely,in the semi-humid region,flowing water is the dominant force,and riparian dunes in this region are formed by aeolian-fluvial interaction.The angle between the wind direction and flow direction in different reaches influences both the supply of sediment sources and the development of riparian dunes.This study will provide a new perspective for evaluating aeolian-fluvial interactions on riparian dunes in the deserts of China’s cold and arid regions.展开更多
The spatial organization of urban-rural systems is fundamentally shaped by the agglomeration and diffusion effects inherent in human-Earth processes,giving rise to distinct gradient-based and hierarchical structures.U...The spatial organization of urban-rural systems is fundamentally shaped by the agglomeration and diffusion effects inherent in human-Earth processes,giving rise to distinct gradient-based and hierarchical structures.Understanding the complexity of these interactions and their multidimensional drivers is essential for deciphering the mechanisms of integrated urban-rural development.Here,we apply a novel hierarchical spatial system framework based on the human-Earth system,combining social network analysis and multi-level modeling,to examine the evolution of the socio-spatial structure in the Beijing-Tianjin-Hebei region from 2000 to 2020.We developed a comprehensive evaluation system spanning economic,social,environmental,and infrastructural dimensions to characterize spatial patterns across multiple network levels,including city clusters,metropolitan areas,municipal-counties,towns,and villages.Our analysis reveals three key findings:First,the density of foundational network connections increased significantly,reflecting a trend toward spatial concentration driven by policy-led regional integration.Second,network structures at the city-cluster and metropolitan scales exhibited a pattern of“initial expansion followed by convergence”,accompanied by notable shifts in their spatial centers of gravity.In parallel,differentiated patterns of agglomeration and expansion were evident in the township-and village-level networks of Baoding,Tangshan,and Handan,while village-level networks in Anxin,Quyang,and other locations demonstrated distinct developmental trends.Third,community structures demonstrated strong functional homophily and interactive cohesion across multiple dimensions,with metropolitan and township communities undergoing restructuring that reflects a reconfiguration of cross-level influence and functional coupling.Spatially,the system manifests as a gradient structure of interwoven point,line,and area networks,establishing a mechanism for functional differentiation and transmission from rural to urban areas.This study provides theoretical foundations and methodological support for understanding the spatial organization logic of integrated urban-rural development,offering practical reference value for advancing regional coordination and rural revitalization in a scientifically informed manner.展开更多
Compared with traditional energy sources,wind power has a lower environmental impact.However,emissions are still generated across the life cycle of wind turbines,from production to recycling.As wind power rapidly deve...Compared with traditional energy sources,wind power has a lower environmental impact.However,emissions are still generated across the life cycle of wind turbines,from production to recycling.As wind power rapidly develops and deployment increases,these impacts are becoming increasingly evident.A comprehensive understanding of these impacts is crucial for sustainable development.Based on the harmonization of previous detailed life cycle assessment(LCA)studies,this study develops a simplified LCA model that estimates the life cycle environmental impacts of wind turbines based on their nominal power.Using this simplified LCA model,we assess the global warming potential(GWP),acidification potential(AP),and cumulative energy demand(CED)of wind power at the regional scale for 2022 and under three future scenarios(high-power wind turbine promotion,reduced wind curtailment,and a comprehensive development scenario).The results indicate that in 2022,the life cycle GWP,AP,and CED of wind power in western China were 10.76 g CO_(2) eq/kWh,0.177 g SO_(2) eq/kWh,and 17.6 kJ/kWh,respectively.Scenario simulations suggest that reducing wind curtailment is the most effective approach for reducing emissions in Inner Mongolia,Gansu,Qinghai,Ningxia,and Xinjiang,producing average decreases of 8.64%in GWP,8.39%in AP,and 9.26%in CED.In contrast,for Guangxi,Chongqing,Sichuan,Guizhou,Yunnan,Xizang,and Shaanxi,the promotion of high-power wind turbines provides greater environmental benefits than reducing curtailment,producing average decreases of 3.45%,3.09%,and 4.29%in GWP,AP,and CED,respectively.These findings help clarify the environmental impact of wind power across its life cycle at the regional scale and provide theoretical references for the direction of future wind power development and the formulation of related policies.展开更多
A greater understanding of the interactions among water,food,and carbon is needed to promote the sustainable development of the Yangtze River Basin(YRB),China.In this study,we calculated the water yield(WY),food suppl...A greater understanding of the interactions among water,food,and carbon is needed to promote the sustainable development of the Yangtze River Basin(YRB),China.In this study,we calculated the water yield(WY),food supply(FS),and carbon sequestra-tion(CS)services of the YRB in 2000,2010,and 2020 via the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.Then,we used the correlation coefficient and spatial clustering methods to analyse the coupling relationships among WY,FS,and CS.Finally,we identified the main factors of the water-food-carbon(WFC)coupling system via the optimal parameter geographic detector.The results showed that WY,FS,and CS in the YRB have degraded from 2010 to 2020 with reductions of-6.30%,-0.13%,and-0.31%,respectively.A notable trade-off relationship existed between FS and CS,with correlation coefficients of-0.63 in 2000,-0.62 in 2010,and-0.60 in 2020.From 2000 to 2020,the area proportion of the grassland low-service bundle decreased from 28.18% to 25.05%,whereas that of the ecologically balanced bundle increased from 23.24%to 24.85%.Distance to cropland,distance to forested land,and land use were the main driving factors for the WFC coupling system in the YRB,with explanatory power of 0.72,0.43,and 0.87 in 2010,respectively.These findings provide scientific theoretical support for achieving food security,water security,carbon neut-rality and peak carbon goals in the YRB.展开更多
Resilience plays a crucial role in maintaining desirable ecosystem states and is a key objective of sustainable ecosystem management.This study synthesizes the concepts and measurement approaches of terrestrial ecosys...Resilience plays a crucial role in maintaining desirable ecosystem states and is a key objective of sustainable ecosystem management.This study synthesizes the concepts and measurement approaches of terrestrial ecosystem resilience and expounded on its spatio-temporal changes and influencing factors based on the literature over the past 50 years.Arid regions exhibited the lowest levels of spatial resilience,and the global ecosystem resilience showed a downward trend.In the focal regions,ecological resilience in Amazonian and Southeast Asian rainforest regions declined primarily driven by human activities such as deforestation and cropland expansion.Precipitation and temperature exerted bidirectional influences the resilience of ecosystems,indicating that ecosystem responses to climatic factors were non-monotonic.Evidence concerning anthropogenic factors such as land management and deforestation on ecosystem resilience were predominantly negative.Overall,this study provides a comprehensive synthesis of large scale terrestrial ecosystem resilience assessments,offering valuable insights for ecosystem protection and restoration policy development.展开更多
Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and...Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and where current projections agree or disagree remains unknown.Here,we systematically compare existing global projections that are consistent with the Shared Socioeconomic Pathways.We find that the total global urban land area is expected to increase by 112%between 2020 and 2100(averaged across all projections),with a coefficient of variation of 0.81.This variation is mostly caused by the selection of the underlying drivers that are included in the different models.Regionally,the highest average growth rates are found in sub-Saharan Africa(+679%to+730%),while this region also has the highest variation across projections(coefficient of variation ranging from 2.02 to 2.18).When ranking scenarios within a study from the highest to the lowest projected increase in urban land,rankings are relatively similar for regions in the Global North,but not for regions in the Global South.The large disagreement across projections can lead to high uncertainties in assessments of future urban land change impacts,which can undermine the effectiveness of long-term planning,policymaking,and resource management decisions.展开更多
Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to h...Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to heat stress(PEHS)under different Shared Socioeconomic Pathways(SSPs)and Representative Concentration Pathways(RCPs)scenarios using a novel decomposition framework that separates the contributions of climate change,population change,and their interaction.Results show that global PEHS will increase substantially during the 21st century,with low-latitude regions experiencing the largest absolute increases,and high-latitude regions facing the largest relative increases.Globally,projected increases in PEHS under SSP3-7.0 are roughly three times those under SSP1-2.6,with low latitudes contributing about 70%-75%of the global total.SSP1-2.6 most effectively limits future heat exposure,with the highest risks in low-latitude developing regions,underscoring the need for low-emission pathways and targeted population and urbanization management.The findings highlight the urgent need for both climate mitigation and population adaptation strategies to address the growing and uneven heat exposure risks worldwide.展开更多
Since 2005,dozens of geographical observational stations have been established in the Heihe River Basin(HRB),and by now a large amount of meteorological,hydrological,and ecological observations as well as data pertain...Since 2005,dozens of geographical observational stations have been established in the Heihe River Basin(HRB),and by now a large amount of meteorological,hydrological,and ecological observations as well as data pertaining to water resources,soil and vegetation have been collected.To adequately analyze these available data and data to be further collected in future,we present a perspective from complexity theory.The concrete materials covered include a presentation of adaptive multiscale filter,which can readily determine arbitrary trends,maximally reduce noise,and reliably perform fractal and multifractal analysis,and a presentation of scale-dependent Lyapunov exponent(SDLE),which can reliably distinguish deterministic chaos from random processes,determine the error doubling time for prediction,and obtain the defining parameters of the process examined.The adaptive filter is illustrated by applying it to obtain the global warming trend and the Atlantic multidecadal oscillation from sea surface temperature data,and by applying it to some variables collected at the HRB to determine diurnal cycle and fractal properties.The SDLE is illustrated to determine intermittent chaos from river flow data.展开更多
The great challenges of sustainable development highlight an urgent need to systematically understand the mech-anisms linking humans and nature.Resources and Environmental Sciences are a broad and practical discipline...The great challenges of sustainable development highlight an urgent need to systematically understand the mech-anisms linking humans and nature.Resources and Environmental Sciences are a broad and practical discipline focused on coupled human and natural systems.They aim to study the formation and evolution of resources in the earth system,the drivers of various environmental problems,processes and relationships between resources and the environment,particularly under the combined impacts of natural conditions and human activities.The major resources and environmental problems drive the discipline development;international science programmes guide the direction of the discipline;interdisciplinary and transdisciplinary integration promotes new branches of the discipline;and technological progress results in a research paradigm shift.Facing the critical research re-quirements of strengthening trans-and interdisciplinarity,breaking through the key technology,targeting major environmental and disaster issues,and supporting sustainable development,nine critical scientific issues should be focused on climate change impact and adaptation,petroleum and mineral resources,water cycle and water re-sources,soil and land resources,ecosystems,remote sensing and geographic information science,environmental science and technology,disaster risk,and global and regional sustainable development.Suggestions to enhancing funding systems,improve talent cultivation,develop scientific platforms,and strength international cooperation are provided in this study to support scientific policymaking.The promotion of Resources and Environmental Sci-ences enables a more comprehensive and in-depth understanding of economic development and environmental changes relevant to assure a more sustainable global development.展开更多
Solar radiation modification,a scheme aimed at mitigating rapid global warming triggered by anthropogenic greenhouse gas emissions,has been explored through the G1ext experiment under the Geoengineering Model Intercom...Solar radiation modification,a scheme aimed at mitigating rapid global warming triggered by anthropogenic greenhouse gas emissions,has been explored through the G1ext experiment under the Geoengineering Model Intercomparison Project(GeoMIP) framework,utilizing the Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0).This paper briefly describes the basic configuration and experimental design of the CAS-ESM2.0 for G1ext,which involves a sudden reduction in solar irradiance to counterbalance the radiative forcing of an abrupt quadrupling of atmospheric CO_(2) concentration,running for 100 years.Preliminary results show that this model can reproduce well the compensatory effect of a uniform decrease in global solar radiation on the radiative forcing resulting from an abrupt quadrupling of CO_(2) concentration.Like other Earth system models,CAS-ESM2.0 reasonably captures variations in radiative adjustments,surface air temperature,and precipitation patterns,both globally and locally,under the G1ext scenario.The generated datasets have been released on the Earth System Grid Federation data server,providing insight into the potential efficacy and impact of solar geoengineering strategies.展开更多
Throughout the contemporary Chinese history of geography,geographical engineering has consistently played a pivotal role as a fundamental scientific activity.It possesses its distinct ontological basis and value orien...Throughout the contemporary Chinese history of geography,geographical engineering has consistently played a pivotal role as a fundamental scientific activity.It possesses its distinct ontological basis and value orientation,rendering it inseparable from being merely a derivative of geographical science or technology.This paper defines geographical engineering and introduces its development history through the lens of Chinese geographical engineering praxises.Furthermore,it is highlighted the logical and functional consistency between the theory of human-earth system and the praxis of geographical engineering.Six modern cases of geographical engineering projects are presented in detail to demonstrate the points and characteristics of different types of modern geographical engineering.Geographical engineering serves as an engine for promoting integrated geography research,and in response to the challenge posed by fragmented geographies,this paper advocates for an urgent revitalization of geographical engineering.The feasibility of revitalizing geographical engineering is guaranteed because it aligns with China’s national strategies.展开更多
Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influenci...Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influencing factors of SM in these areas remains insufficient.This study investigated the spatiotemporal variations and influencing factors of SM in arid and semi-arid areas of China by utilizing the extended triple collation(ETC),Mann-Kendall test,Theil-Sen estimator,ridge regression analysis,and other relevant methods.The following findings were obtained:(1)at the pixel scale,the long-term monthly SM data from the European Space Agency Climate Change Initiative(ESA CCI)exhibited the highest correlation coefficient of 0.794 and the lowest root mean square error(RMSE)of 0.014 m^(3)/m^(3);(2)from 2000 to 2022,the study area experienced significant increase in annual average SM,with a rate of 0.408×10^(-3)m^(3)/(m^(3)•a).Moreover,higher altitudes showed a notable upward trend,with SM increasing rates at 0.210×10^(-3)m^(3)/(m^(3)•a)between 1000 and 2000 m,0.530×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m,and 0.760×10^(-3)m^(3)/(m^(3)•a)at altitudes above 4000 m;(3)land surface temperature(LST),root zone soil moisture(RSM)(10-40 cm depth),and normalized difference vegetation index(NDVI)were identified as the primary factors influencing annual average SM,which accounted for 34.37%,24.16%,and 22.64%relative contributions,respectively;and(4)absolute contribution of LST was more significant in subareas at higher altitudes,with average absolute contributions of 0.800×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m and 0.500×10^(-2) m^(3)/(m^(3)•a)above 4000 m.This study reveals the spatiotemporal variations and main influencing factors of SM in Chinese arid and semi-arid areas,highlighting the more pronounced absolute contribution of LST to SM in high-altitude areas,providing valuable insights for ecological research and water resource management in these areas.展开更多
Uncovering the evolution process of rural revitalization level(RRL)in China and elucidating the complex driving mechanism hold significant implications for implementing rural revitalization strategy and advancing rura...Uncovering the evolution process of rural revitalization level(RRL)in China and elucidating the complex driving mechanism hold significant implications for implementing rural revitalization strategy and advancing rural modernization.This study analyzes the spatio-temporal evolution of China's RRL from 2002 to 2022 and reveals its complex driving mechanism.The results show that China's RRL steadily increased from 0.1083 to 0.4463,and the provincial RRL exhibited the characteristic of decreasing successively in the eastern region,the central region,and the western region.The overall differences of RRL are shrinking,and intra-group differences contribute almost 1/3 of the overall variation,more than the contribution of inter-group differences.Although the influencing factors show nonlinear characteristics,on the whole,economic level and human capital exhibit positive effects,while relief degree,urbanization,industrialization,and opening degree exhibit negative effects.Farmland resources and investment intensity exhibit the characteristics of positive effect and negative effect equilibrium.At the regional scale,influencing factors exhibit significant spatio-temporal heterogeneity.In the future,to achieve comprehensive rural revitalization,it is vital to implement systemic policy measures,such as enhancing industrial competitiveness,supplementing rural talents,and optimizing the relations between urban and rural areas as well as between industry and agriculture.展开更多
Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what exten...Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.展开更多
In the context of rapid urbanization and industrialization,achieving a coordinated relationship between urban construction land expansion(UCLE)and economic growth is essential for sustainable development,especially in...In the context of rapid urbanization and industrialization,achieving a coordinated relationship between urban construction land expansion(UCLE)and economic growth is essential for sustainable development,especially in developing countries.This study examined the spatiotemporal relationship between UCLE and economic growth in the Yellow River Basin(YRB),China from 2000 to 2020.An extended IPAT(Impact=Population×Affluence×Technology)decoupling framework and the geographical detector model were employed at a 5-km grid scale.Results show that urban construction land(UCL)expanded slowly before 2005,accelerated between 2005 and 2015,and declined thereafter.Since 2015,UCLE in most parts of the YRB has gradually decoupled from economic growth.The geographical detector analysis revealed that economic growth,along with its interactions with natural,locational,and socioeconomic factors,significantly influenced UCLE.Notably,location factors have gained importance since 2015,reducing the role of economic growth as the primary driver of UCLE in the YRB’s lower reaches.Nonetheless,economic growth continues to significantly influence the upper and middle reaches.These findings highlight the need for more precise and differentiated strategies for land utilization and economic growth,tailored to finer spatial scales,to better integrate human-land systems and promote high-quality regional development.展开更多
Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrat...Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrate multiple drought characteristics,resulting in incomplete evaluations.To address this limitation,this study introduced the drought comprehensive propagation intensity(DCPI)index,a systematic tool that quantifies propagation intensity and incorporates five drought characteristic indicators(drought frequency,total duration,maximum duration,coverage,and degree)to assess the comprehensive drought intensity in the upper Shiyang River Basin,China from 1961 to 2023.The results indicated that pre-1980s drought propagation was relatively weak(DCPI<0.964),reflecting stable hydrological homeostasis.After the 1980s,the intensity significantly increased,peaking at 5.530(rather strong drought)in the 2000s due to human-induced alterations in surface runoff and ecological changes.Spatially,the western tributaries(e.g.,the Xida River Watershed)presented stronger hydrological drought intensity,whereas the eastern tributaries(e.g.,the Huangyang,Gulang,and Dajing river watersheds)presented higher meteorological drought intensity.The DCPI values decreased from west to east,with near peer-to-peer propagation observed in the Dongda,Huangyang,and Jinta river watersheds,suggesting minimal human interference.A nonlinear relationship between meteorological and hydrological droughts was identified,with severe drought frequency and duration emerging as critical drivers of propagation intensity.Notably,trends of meteorological humidification coexist with hydrological aridification,highlighting systemic challenges for water resource management.The DCPI framework enhances the understanding of drought mechanisms by enabling a structured evaluation of drought impacts,which is essential for developing effective water resource strategies and ecological restoration efforts in arid areas.This study underscores the importance of integrating multi-dimensional drought characteristics to improve prediction accuracy and inform policy decisions.展开更多
As urbanization accelerates,rural regions in China are experiencing transformative changes.This study examines thetransformation mechanism of modern agricultural villages in the loess hilly and gully regions,using Zha...As urbanization accelerates,rural regions in China are experiencing transformative changes.This study examines thetransformation mechanism of modern agricultural villages in the loess hilly and gully regions,using ZhaojiawaVillage in ShannxiProvince of China as a case study.In this study,we explored the village’s evolution amid China’s rural revitalization efforts,highlighting the transition from a traditional agricultural village to a modern agricultural village in the context of rapid urbanization.This study employed actor-network theory(ANT)to investigate the complex interactions among diverse actors that drive rural transformation.ANT interlinks spatial relationships with intricate social networks.We utilized Google Earth remote sensing images in2015 and 2021 and interview data to construct ANT.Three key dimensions of rural transformationare identified:economic structure transformation,social relationship reorganization,and spatial layout reconstruction.The transformation mechanism in ZhaojiawaVillage is underpinned by a network of diverse actors,both human and non-human,aligned around two pivotal stages of agricultural village development(i.e.,construction stage and development stage).In the initial construction stage,the Suide County government led a complex actor network to enhance rural living and production spaces.In the development stage,the village committee emerged as a central actor,with increased participation from villagers and external enterprises,facilitating the creation of a multifunctional space.The evolving goals and roles of these key actors contributed to the reconfiguration of the actor network,promoting rural transformation.These insights are applicable to other ecologically vulnerable and economically challenged rural areasin the loess hilly and gully regions,suggesting that collaboration amongstakeholders can effectively facilitate the transition to specialized and integrated industries,thereby fostering rural revitalization.展开更多
China boasts over 10,000 native useful vascular plants(NUVPs),spanning eight families and serving twelve dis-tinct uses.Given the importance of NUVPs,widely-confirmed in-situ conservation policies,such as establishing...China boasts over 10,000 native useful vascular plants(NUVPs),spanning eight families and serving twelve dis-tinct uses.Given the importance of NUVPs,widely-confirmed in-situ conservation policies,such as establishing nature reserves,have been broadly implemented to protect them.However,the effectiveness of in-situ conser-vation efforts for NUVPs in China remains uncertain.Highlighting the importance of multi-family and multi-use plants,this research identified the spatial distribution pattern and diversity hotspots of NUVPs,evaluated the in-situ conservation effectiveness and provided the future conservation priority scheme.The results revealed that the spatial concentration of NUVPs is predominantly in the southwestern lowlands of China(<3,000 m),peaking around 109°E and 25°N.Importantly,diversity hotspots exhibited a significant spatial mismatch(over 80%)with the National Nature Reserve(NNR)network.Only about 17.7%and 13.3%of these hotspots are protected by NNR initiatives for endemic and nonendemic species,respectively.Additionally,the proposed Plants Conserva-tion Effectiveness Index(PCEI)proved more representative in addressing the two main crises faced by the studied species-species loss and human pressure,and found a decline in conservation effectiveness as the number of uses increased.Finally,future conservation priorities based on the PCEI highlight the Nanling Mountains,Heng-duan Mountains,Jiuwandashan,and Qilian Mountains as highly prioritized regions requiring focused efforts to address the impacts of climate change.Conversely,in sparsely distributed regions experiencing increasing human pressure,it is imperative to mitigate the expanding human footprint.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP),Grant No.2019QZKK0606.
文摘The Qinghai-Tibet Plateau(QTP)has three main grassland types:alpine meadow,alpine steppe,and alpine desert steppe.In this study,we asked how plant productivity and species diversity vary with altitude,longitude and latitude in alpine grasslands of the QTP.We then identified the environmental factors that drive these observed patterns of plant productivity and species diversity.We found that although plant productivity and species diversity varied greatly across large-scale longitudinal and latitudinal gradients,these changes were strongest across the longitudinal gradient.This finding indicates that moisture rather than temperature has the greatest impact on plant productivity and species diversity of the alpine grasslands in the QTP.We also found that besides soil and climate factors,partial pressure of carbon dioxide(pCO_(2))also has significant effects on plant productivity,and barometric pressure and partial pressure of oxygen(pO_(2))also have significant effects on species diversity.Furthermore,the relationship between the biomass of grassland-dominant species and species diversity was affected by the spatial scale at which these factors were studied.Our study provides new insights into the interconnections between plant productivity and species diversity and the major factors that influence alpine grasslands.It also provides a scientific basis for the maintenance of plant diversity and ecosystem functions in hypoxic(low-oxygen)regions.
基金Under the auspices of the Third Xinjiang Scientific Expedition Program(No.2022xjkk0600)。
文摘The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.
基金Under the auspices of the General Project of Science and Technology Department of Shaanxi Province(No.2023-JCYB-264)General Program of National Natural Science Foundation of China(No.41801004,42371008,42471012)。
文摘Riparian dunes in deserts exhibit unique geographic features due to aeolian-fluvial interactions.In this study,we collected 510 surface sediment samples from eight drainage basins and conducted a systematic analysis to examine the grain size characteristics of major riparian dunes in the typical cold and arid deserts of China.The results indicate that major riparian dunes of deserts in study area can be classified into three types based on their grain size characteristics.The Bartlett test of sphericity and the Kaiser-Meyer-Olkin(KMO)test were also performed,and their significance values were found to be 0.000 and 0.584,respectively.The results of the principal component analysis revealed that the cumulative contribution rate of the total variance reached 85.9%for the two principal components with characteristic roots greater than 1.0.The primary principal component included medium sand,whereas the secondary principal component included fine sand.We conducted a cluster analysis and classified the samples into three major types.Type I rivers include the Keriya River,Langqu River,Tora River and Heihe River,which are characterized by by fine particle size,and well-sorted.Type II includes Mu Bulag River,Kuye River,and the Xar Moron River,Compared with type I,it has a relatively coarser mean grain size and relatively poor sorting for this type.Type III includes the Maquan River,which is characterized mainly by fine sand and medium sand,accounting for more than 90%,and the sorting coefficient(0.52)suggests relatively well sorting in this pattern.Moreover,principal component analysis was applied to determine the particle sizes of samples from different watersheds.Moreover,these sediments exhibit both hydromorphic and aeolian features.At the drainage basin scale,the mode and intensity of aeolian-fluvial interactions depend on climatic conditions.In arid and semi-arid climate regions,wind is the dominant force,and the grain size exhibits significant aeolian features.Conversely,in the semi-humid region,flowing water is the dominant force,and riparian dunes in this region are formed by aeolian-fluvial interaction.The angle between the wind direction and flow direction in different reaches influences both the supply of sediment sources and the development of riparian dunes.This study will provide a new perspective for evaluating aeolian-fluvial interactions on riparian dunes in the deserts of China’s cold and arid regions.
基金supported by the National Natural Science Foundation of China(Grant Nos.42293270,42530712)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.42401334).
文摘The spatial organization of urban-rural systems is fundamentally shaped by the agglomeration and diffusion effects inherent in human-Earth processes,giving rise to distinct gradient-based and hierarchical structures.Understanding the complexity of these interactions and their multidimensional drivers is essential for deciphering the mechanisms of integrated urban-rural development.Here,we apply a novel hierarchical spatial system framework based on the human-Earth system,combining social network analysis and multi-level modeling,to examine the evolution of the socio-spatial structure in the Beijing-Tianjin-Hebei region from 2000 to 2020.We developed a comprehensive evaluation system spanning economic,social,environmental,and infrastructural dimensions to characterize spatial patterns across multiple network levels,including city clusters,metropolitan areas,municipal-counties,towns,and villages.Our analysis reveals three key findings:First,the density of foundational network connections increased significantly,reflecting a trend toward spatial concentration driven by policy-led regional integration.Second,network structures at the city-cluster and metropolitan scales exhibited a pattern of“initial expansion followed by convergence”,accompanied by notable shifts in their spatial centers of gravity.In parallel,differentiated patterns of agglomeration and expansion were evident in the township-and village-level networks of Baoding,Tangshan,and Handan,while village-level networks in Anxin,Quyang,and other locations demonstrated distinct developmental trends.Third,community structures demonstrated strong functional homophily and interactive cohesion across multiple dimensions,with metropolitan and township communities undergoing restructuring that reflects a reconfiguration of cross-level influence and functional coupling.Spatially,the system manifests as a gradient structure of interwoven point,line,and area networks,establishing a mechanism for functional differentiation and transmission from rural to urban areas.This study provides theoretical foundations and methodological support for understanding the spatial organization logic of integrated urban-rural development,offering practical reference value for advancing regional coordination and rural revitalization in a scientifically informed manner.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF1303405).
文摘Compared with traditional energy sources,wind power has a lower environmental impact.However,emissions are still generated across the life cycle of wind turbines,from production to recycling.As wind power rapidly develops and deployment increases,these impacts are becoming increasingly evident.A comprehensive understanding of these impacts is crucial for sustainable development.Based on the harmonization of previous detailed life cycle assessment(LCA)studies,this study develops a simplified LCA model that estimates the life cycle environmental impacts of wind turbines based on their nominal power.Using this simplified LCA model,we assess the global warming potential(GWP),acidification potential(AP),and cumulative energy demand(CED)of wind power at the regional scale for 2022 and under three future scenarios(high-power wind turbine promotion,reduced wind curtailment,and a comprehensive development scenario).The results indicate that in 2022,the life cycle GWP,AP,and CED of wind power in western China were 10.76 g CO_(2) eq/kWh,0.177 g SO_(2) eq/kWh,and 17.6 kJ/kWh,respectively.Scenario simulations suggest that reducing wind curtailment is the most effective approach for reducing emissions in Inner Mongolia,Gansu,Qinghai,Ningxia,and Xinjiang,producing average decreases of 8.64%in GWP,8.39%in AP,and 9.26%in CED.In contrast,for Guangxi,Chongqing,Sichuan,Guizhou,Yunnan,Xizang,and Shaanxi,the promotion of high-power wind turbines provides greater environmental benefits than reducing curtailment,producing average decreases of 3.45%,3.09%,and 4.29%in GWP,AP,and CED,respectively.These findings help clarify the environmental impact of wind power across its life cycle at the regional scale and provide theoretical references for the direction of future wind power development and the formulation of related policies.
基金Under the auspices of the National Natural Science Foundation of China(No.U24A20580,42201333,42171298)Natural Science Foundation of Chongqing(No.CSTB2023NSCQ-LZX0009,CSTB2022NSCQ-BHX0734)+1 种基金General Program of National Social Science Foundation in China(No.25BJY215)Research and Innovation Program for Graduate Students in Chongqing(No.CYS25587)。
文摘A greater understanding of the interactions among water,food,and carbon is needed to promote the sustainable development of the Yangtze River Basin(YRB),China.In this study,we calculated the water yield(WY),food supply(FS),and carbon sequestra-tion(CS)services of the YRB in 2000,2010,and 2020 via the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.Then,we used the correlation coefficient and spatial clustering methods to analyse the coupling relationships among WY,FS,and CS.Finally,we identified the main factors of the water-food-carbon(WFC)coupling system via the optimal parameter geographic detector.The results showed that WY,FS,and CS in the YRB have degraded from 2010 to 2020 with reductions of-6.30%,-0.13%,and-0.31%,respectively.A notable trade-off relationship existed between FS and CS,with correlation coefficients of-0.63 in 2000,-0.62 in 2010,and-0.60 in 2020.From 2000 to 2020,the area proportion of the grassland low-service bundle decreased from 28.18% to 25.05%,whereas that of the ecologically balanced bundle increased from 23.24%to 24.85%.Distance to cropland,distance to forested land,and land use were the main driving factors for the WFC coupling system in the YRB,with explanatory power of 0.72,0.43,and 0.87 in 2010,respectively.These findings provide scientific theoretical support for achieving food security,water security,carbon neut-rality and peak carbon goals in the YRB.
基金supported by the National Natural Science Foundation of China(Grants No.42522105 and 42171088)the 111 Project of China(Grant No.B23027)the Fundamental Research Funds for the Central Universities of China.
文摘Resilience plays a crucial role in maintaining desirable ecosystem states and is a key objective of sustainable ecosystem management.This study synthesizes the concepts and measurement approaches of terrestrial ecosystem resilience and expounded on its spatio-temporal changes and influencing factors based on the literature over the past 50 years.Arid regions exhibited the lowest levels of spatial resilience,and the global ecosystem resilience showed a downward trend.In the focal regions,ecological resilience in Amazonian and Southeast Asian rainforest regions declined primarily driven by human activities such as deforestation and cropland expansion.Precipitation and temperature exerted bidirectional influences the resilience of ecosystems,indicating that ecosystem responses to climatic factors were non-monotonic.Evidence concerning anthropogenic factors such as land management and deforestation on ecosystem resilience were predominantly negative.Overall,this study provides a comprehensive synthesis of large scale terrestrial ecosystem resilience assessments,offering valuable insights for ecosystem protection and restoration policy development.
基金supported by the Netherlands Organization for Scientific Research NWO in the form of a VIDI grant(Grant No.VI.Vidi.198.008).
文摘Projections of future urban land change are essential for a range of sustainability assessments,including those related to biodiversity loss,carbon emissions,and agricultural land conversion.However,to what extent and where current projections agree or disagree remains unknown.Here,we systematically compare existing global projections that are consistent with the Shared Socioeconomic Pathways.We find that the total global urban land area is expected to increase by 112%between 2020 and 2100(averaged across all projections),with a coefficient of variation of 0.81.This variation is mostly caused by the selection of the underlying drivers that are included in the different models.Regionally,the highest average growth rates are found in sub-Saharan Africa(+679%to+730%),while this region also has the highest variation across projections(coefficient of variation ranging from 2.02 to 2.18).When ranking scenarios within a study from the highest to the lowest projected increase in urban land,rankings are relatively similar for regions in the Global North,but not for regions in the Global South.The large disagreement across projections can lead to high uncertainties in assessments of future urban land change impacts,which can undermine the effectiveness of long-term planning,policymaking,and resource management decisions.
基金funded by National Natural Science Foundation of China(Grant No.42271273)Swedish Research Council(VR:2021-02163).
文摘Global warming and socioeconomic development are expected to exacerbate human exposure to heat stress,but the extent and inequality of such changes remain unclear.Here,we quantified the future population exposure to heat stress(PEHS)under different Shared Socioeconomic Pathways(SSPs)and Representative Concentration Pathways(RCPs)scenarios using a novel decomposition framework that separates the contributions of climate change,population change,and their interaction.Results show that global PEHS will increase substantially during the 21st century,with low-latitude regions experiencing the largest absolute increases,and high-latitude regions facing the largest relative increases.Globally,projected increases in PEHS under SSP3-7.0 are roughly three times those under SSP1-2.6,with low latitudes contributing about 70%-75%of the global total.SSP1-2.6 most effectively limits future heat exposure,with the highest risks in low-latitude developing regions,underscoring the need for low-emission pathways and targeted population and urbanization management.The findings highlight the urgent need for both climate mitigation and population adaptation strategies to address the growing and uneven heat exposure risks worldwide.
基金National Natural Science Foundation of China,No.71661002,No.41671532National Key R&D Program of China,No.2017YFB0504102The Fundamental Research Funds for the Central Universities
文摘Since 2005,dozens of geographical observational stations have been established in the Heihe River Basin(HRB),and by now a large amount of meteorological,hydrological,and ecological observations as well as data pertaining to water resources,soil and vegetation have been collected.To adequately analyze these available data and data to be further collected in future,we present a perspective from complexity theory.The concrete materials covered include a presentation of adaptive multiscale filter,which can readily determine arbitrary trends,maximally reduce noise,and reliably perform fractal and multifractal analysis,and a presentation of scale-dependent Lyapunov exponent(SDLE),which can reliably distinguish deterministic chaos from random processes,determine the error doubling time for prediction,and obtain the defining parameters of the process examined.The adaptive filter is illustrated by applying it to obtain the global warming trend and the Atlantic multidecadal oscillation from sea surface temperature data,and by applying it to some variables collected at the HRB to determine diurnal cycle and fractal properties.The SDLE is illustrated to determine intermittent chaos from river flow data.
基金This work was supported by the National Natural Science Foundation of China(Grant No.L1924041)Research Project on the Discipline De-velopment Strategy of Academic Divisions of the Chinese Academy of Sciences(Grant No.XK2019DXC006),and the Fundamental Research Funds for the Central Universities in China.
文摘The great challenges of sustainable development highlight an urgent need to systematically understand the mech-anisms linking humans and nature.Resources and Environmental Sciences are a broad and practical discipline focused on coupled human and natural systems.They aim to study the formation and evolution of resources in the earth system,the drivers of various environmental problems,processes and relationships between resources and the environment,particularly under the combined impacts of natural conditions and human activities.The major resources and environmental problems drive the discipline development;international science programmes guide the direction of the discipline;interdisciplinary and transdisciplinary integration promotes new branches of the discipline;and technological progress results in a research paradigm shift.Facing the critical research re-quirements of strengthening trans-and interdisciplinarity,breaking through the key technology,targeting major environmental and disaster issues,and supporting sustainable development,nine critical scientific issues should be focused on climate change impact and adaptation,petroleum and mineral resources,water cycle and water re-sources,soil and land resources,ecosystems,remote sensing and geographic information science,environmental science and technology,disaster risk,and global and regional sustainable development.Suggestions to enhancing funding systems,improve talent cultivation,develop scientific platforms,and strength international cooperation are provided in this study to support scientific policymaking.The promotion of Resources and Environmental Sci-ences enables a more comprehensive and in-depth understanding of economic development and environmental changes relevant to assure a more sustainable global development.
基金supported by the National Natural Science Foundation of China(Grant No.41875126)the National Key Scientific and Technological Infrastructure project “Earth System Numerical Simulation Facility”(EarthLab)。
文摘Solar radiation modification,a scheme aimed at mitigating rapid global warming triggered by anthropogenic greenhouse gas emissions,has been explored through the G1ext experiment under the Geoengineering Model Intercomparison Project(GeoMIP) framework,utilizing the Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0).This paper briefly describes the basic configuration and experimental design of the CAS-ESM2.0 for G1ext,which involves a sudden reduction in solar irradiance to counterbalance the radiative forcing of an abrupt quadrupling of atmospheric CO_(2) concentration,running for 100 years.Preliminary results show that this model can reproduce well the compensatory effect of a uniform decrease in global solar radiation on the radiative forcing resulting from an abrupt quadrupling of CO_(2) concentration.Like other Earth system models,CAS-ESM2.0 reasonably captures variations in radiative adjustments,surface air temperature,and precipitation patterns,both globally and locally,under the G1ext scenario.The generated datasets have been released on the Earth System Grid Federation data server,providing insight into the potential efficacy and impact of solar geoengineering strategies.
基金Under the auspices of National Natural Science Foundation of China(No.42293270)。
文摘Throughout the contemporary Chinese history of geography,geographical engineering has consistently played a pivotal role as a fundamental scientific activity.It possesses its distinct ontological basis and value orientation,rendering it inseparable from being merely a derivative of geographical science or technology.This paper defines geographical engineering and introduces its development history through the lens of Chinese geographical engineering praxises.Furthermore,it is highlighted the logical and functional consistency between the theory of human-earth system and the praxis of geographical engineering.Six modern cases of geographical engineering projects are presented in detail to demonstrate the points and characteristics of different types of modern geographical engineering.Geographical engineering serves as an engine for promoting integrated geography research,and in response to the challenge posed by fragmented geographies,this paper advocates for an urgent revitalization of geographical engineering.The feasibility of revitalizing geographical engineering is guaranteed because it aligns with China’s national strategies.
基金supported by the Natural Science Foundation of Henan Province(252300421290)the National Natural Science Foundation of China(41771438)+1 种基金the Program for Innovative Research Team(in Science and Technology)of Henan University(22IRTSTHN010)the Postgraduate Education Reform and Quality Improvement Project of Henan Province(HNYJS2020JD14).
文摘Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influencing factors of SM in these areas remains insufficient.This study investigated the spatiotemporal variations and influencing factors of SM in arid and semi-arid areas of China by utilizing the extended triple collation(ETC),Mann-Kendall test,Theil-Sen estimator,ridge regression analysis,and other relevant methods.The following findings were obtained:(1)at the pixel scale,the long-term monthly SM data from the European Space Agency Climate Change Initiative(ESA CCI)exhibited the highest correlation coefficient of 0.794 and the lowest root mean square error(RMSE)of 0.014 m^(3)/m^(3);(2)from 2000 to 2022,the study area experienced significant increase in annual average SM,with a rate of 0.408×10^(-3)m^(3)/(m^(3)•a).Moreover,higher altitudes showed a notable upward trend,with SM increasing rates at 0.210×10^(-3)m^(3)/(m^(3)•a)between 1000 and 2000 m,0.530×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m,and 0.760×10^(-3)m^(3)/(m^(3)•a)at altitudes above 4000 m;(3)land surface temperature(LST),root zone soil moisture(RSM)(10-40 cm depth),and normalized difference vegetation index(NDVI)were identified as the primary factors influencing annual average SM,which accounted for 34.37%,24.16%,and 22.64%relative contributions,respectively;and(4)absolute contribution of LST was more significant in subareas at higher altitudes,with average absolute contributions of 0.800×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m and 0.500×10^(-2) m^(3)/(m^(3)•a)above 4000 m.This study reveals the spatiotemporal variations and main influencing factors of SM in Chinese arid and semi-arid areas,highlighting the more pronounced absolute contribution of LST to SM in high-altitude areas,providing valuable insights for ecological research and water resource management in these areas.
基金National Natural Science Foundation of China,No.42293271The Alliance of International Science Organizations,No.ANSO-PA-2023-16。
文摘Uncovering the evolution process of rural revitalization level(RRL)in China and elucidating the complex driving mechanism hold significant implications for implementing rural revitalization strategy and advancing rural modernization.This study analyzes the spatio-temporal evolution of China's RRL from 2002 to 2022 and reveals its complex driving mechanism.The results show that China's RRL steadily increased from 0.1083 to 0.4463,and the provincial RRL exhibited the characteristic of decreasing successively in the eastern region,the central region,and the western region.The overall differences of RRL are shrinking,and intra-group differences contribute almost 1/3 of the overall variation,more than the contribution of inter-group differences.Although the influencing factors show nonlinear characteristics,on the whole,economic level and human capital exhibit positive effects,while relief degree,urbanization,industrialization,and opening degree exhibit negative effects.Farmland resources and investment intensity exhibit the characteristics of positive effect and negative effect equilibrium.At the regional scale,influencing factors exhibit significant spatio-temporal heterogeneity.In the future,to achieve comprehensive rural revitalization,it is vital to implement systemic policy measures,such as enhancing industrial competitiveness,supplementing rural talents,and optimizing the relations between urban and rural areas as well as between industry and agriculture.
基金National Natural Science Foundation of China,No.41761003The Karst Science Research Center of Guizhou Province,No.U1812401。
文摘Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide(CO_(2))fertilization in hot and humid regions.The subtropical humid karst region is a hot and humid region;whether and to what extent CO_(2)fertilization affects vegetation changes in such regions remains unclear.In this study,we investigated the degree to which CO_(2)fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression analysis.Results showed that CO_(2)fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO_(2)fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau region.Previous studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these changes.The findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.
基金Under the auspices of National Natural Science Foundation of China(No.42293271,42471222)。
文摘In the context of rapid urbanization and industrialization,achieving a coordinated relationship between urban construction land expansion(UCLE)and economic growth is essential for sustainable development,especially in developing countries.This study examined the spatiotemporal relationship between UCLE and economic growth in the Yellow River Basin(YRB),China from 2000 to 2020.An extended IPAT(Impact=Population×Affluence×Technology)decoupling framework and the geographical detector model were employed at a 5-km grid scale.Results show that urban construction land(UCL)expanded slowly before 2005,accelerated between 2005 and 2015,and declined thereafter.Since 2015,UCLE in most parts of the YRB has gradually decoupled from economic growth.The geographical detector analysis revealed that economic growth,along with its interactions with natural,locational,and socioeconomic factors,significantly influenced UCLE.Notably,location factors have gained importance since 2015,reducing the role of economic growth as the primary driver of UCLE in the YRB’s lower reaches.Nonetheless,economic growth continues to significantly influence the upper and middle reaches.These findings highlight the need for more precise and differentiated strategies for land utilization and economic growth,tailored to finer spatial scales,to better integrate human-land systems and promote high-quality regional development.
基金supported by the National Natural Science Foundation of China(42475177,41877521)the National Key Research and Development Program of China(2023YFC3008505,2016YFA0602402).
文摘Comprehensively revealing the intensity of drought propagation from meteorological to hydrological drought is crucial for effective drought monitoring and management.However,existing assessments often fail to integrate multiple drought characteristics,resulting in incomplete evaluations.To address this limitation,this study introduced the drought comprehensive propagation intensity(DCPI)index,a systematic tool that quantifies propagation intensity and incorporates five drought characteristic indicators(drought frequency,total duration,maximum duration,coverage,and degree)to assess the comprehensive drought intensity in the upper Shiyang River Basin,China from 1961 to 2023.The results indicated that pre-1980s drought propagation was relatively weak(DCPI<0.964),reflecting stable hydrological homeostasis.After the 1980s,the intensity significantly increased,peaking at 5.530(rather strong drought)in the 2000s due to human-induced alterations in surface runoff and ecological changes.Spatially,the western tributaries(e.g.,the Xida River Watershed)presented stronger hydrological drought intensity,whereas the eastern tributaries(e.g.,the Huangyang,Gulang,and Dajing river watersheds)presented higher meteorological drought intensity.The DCPI values decreased from west to east,with near peer-to-peer propagation observed in the Dongda,Huangyang,and Jinta river watersheds,suggesting minimal human interference.A nonlinear relationship between meteorological and hydrological droughts was identified,with severe drought frequency and duration emerging as critical drivers of propagation intensity.Notably,trends of meteorological humidification coexist with hydrological aridification,highlighting systemic challenges for water resource management.The DCPI framework enhances the understanding of drought mechanisms by enabling a structured evaluation of drought impacts,which is essential for developing effective water resource strategies and ecological restoration efforts in arid areas.This study underscores the importance of integrating multi-dimensional drought characteristics to improve prediction accuracy and inform policy decisions.
基金supported by the National Natural Science Foundation of China(42293272,42071227).
文摘As urbanization accelerates,rural regions in China are experiencing transformative changes.This study examines thetransformation mechanism of modern agricultural villages in the loess hilly and gully regions,using ZhaojiawaVillage in ShannxiProvince of China as a case study.In this study,we explored the village’s evolution amid China’s rural revitalization efforts,highlighting the transition from a traditional agricultural village to a modern agricultural village in the context of rapid urbanization.This study employed actor-network theory(ANT)to investigate the complex interactions among diverse actors that drive rural transformation.ANT interlinks spatial relationships with intricate social networks.We utilized Google Earth remote sensing images in2015 and 2021 and interview data to construct ANT.Three key dimensions of rural transformationare identified:economic structure transformation,social relationship reorganization,and spatial layout reconstruction.The transformation mechanism in ZhaojiawaVillage is underpinned by a network of diverse actors,both human and non-human,aligned around two pivotal stages of agricultural village development(i.e.,construction stage and development stage).In the initial construction stage,the Suide County government led a complex actor network to enhance rural living and production spaces.In the development stage,the village committee emerged as a central actor,with increased participation from villagers and external enterprises,facilitating the creation of a multifunctional space.The evolving goals and roles of these key actors contributed to the reconfiguration of the actor network,promoting rural transformation.These insights are applicable to other ecologically vulnerable and economically challenged rural areasin the loess hilly and gully regions,suggesting that collaboration amongstakeholders can effectively facilitate the transition to specialized and integrated industries,thereby fostering rural revitalization.
基金supported by the National Natural Science Foundation of China(Grant No.42330205)the Open Fund of State Key Labora-tory of Remote Sensing Science and Beijing Engineering Research Center for Global Land Remote Sensing Products(Grant No.OF202206).
文摘China boasts over 10,000 native useful vascular plants(NUVPs),spanning eight families and serving twelve dis-tinct uses.Given the importance of NUVPs,widely-confirmed in-situ conservation policies,such as establishing nature reserves,have been broadly implemented to protect them.However,the effectiveness of in-situ conser-vation efforts for NUVPs in China remains uncertain.Highlighting the importance of multi-family and multi-use plants,this research identified the spatial distribution pattern and diversity hotspots of NUVPs,evaluated the in-situ conservation effectiveness and provided the future conservation priority scheme.The results revealed that the spatial concentration of NUVPs is predominantly in the southwestern lowlands of China(<3,000 m),peaking around 109°E and 25°N.Importantly,diversity hotspots exhibited a significant spatial mismatch(over 80%)with the National Nature Reserve(NNR)network.Only about 17.7%and 13.3%of these hotspots are protected by NNR initiatives for endemic and nonendemic species,respectively.Additionally,the proposed Plants Conserva-tion Effectiveness Index(PCEI)proved more representative in addressing the two main crises faced by the studied species-species loss and human pressure,and found a decline in conservation effectiveness as the number of uses increased.Finally,future conservation priorities based on the PCEI highlight the Nanling Mountains,Heng-duan Mountains,Jiuwandashan,and Qilian Mountains as highly prioritized regions requiring focused efforts to address the impacts of climate change.Conversely,in sparsely distributed regions experiencing increasing human pressure,it is imperative to mitigate the expanding human footprint.
