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spatiotemporal variations of Meteorological Droughts in China During 1961–2014: An Investigation Based on Multi-Threshold Identification

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International Journal of Disaster Risk Science 2016年第1期7卷 63-76页

作者： Jun He Xiaohua Yang Zhe Li Xuejun Zhang Qiuhong Tang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences School of Environment Beijing Normal University University of Chinese Academy of Sciences

As a major agricultural country, China suffers from severe meteorological drought almost every *** studies have applied a single threshold to identify the onset of drought events, which may cause problems to adequately characterize long-term patterns of *** study analyzes meteorological droughts in China based on a set of daily gridded(0.5° 9 0.5°) precipitation data from 1961 to 2014. By using a multi-threshold run theory approach to evaluate the monthly percentage of precipitation anomalies index(Pa), a drought events sequence was identified at each grid cell. The spatiotemporal variations of drought in China were further investigated based on statistics of the frequency, duration,severity, and intensity of all drought events. Analysis of the results show that China has five distinct meteorological drought-prone regions: the Huang-Huai-Hai Plain, Northeast China, Southwest China, South China coastal region,and Northwest China. Seasonal analysis further indicates that there are evident spatial variations in the seasonal contribution to regional drought. But overall, most contribution to annual drought events in China come from the winter. Decadal variation analysis suggests that most of China's water resource regions have undergone an increase in drought frequency, especially in the Liaohe, Haihe, and Yellow River basins, although drought duration and severity clearly have decreased after the 1960 s.

关键词： China Meteorological drought Multi-threshold run theory method spatiotemporal variations

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spatiotemporal variations and Controls on Anthropogenic Heat Fluxes in 12 Selected Cities in the Eastern China

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Chinese Geographical Science 2021年第3期31卷 444-458页

作者： CAO Zheng WEN Ya SONG Song HUNG Chak Ho SUN Hui School of Geographical Sciences Guangzhou UniversityGuangzhou 510006China Guangdong Province Engineering Technology Research Center for Geographical Conditions Monitoring and Comprehensive Analysis Guangzhou 510006China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China College of Resources and Environment South China Agricultural UniversityGuangzhou 510642China S.Department of Urban Planning and Design The University of Hong KongHong Kong 999077China

spatiotemporal variations of anthropogenic heat flux(AHF)is reported to be associated with global ***,confined to the low spatial resolution of energy consumption statistical data,details of AHF was not well *** obtain high spatial resolution data of AHF,Defense Meteorological Satellite Program/Operational Linescan System(DMSP/OLS)nighttime light time-series product and Moderate Resolution Imaging Spectroradiometer(MODIS)satellite monthly normalized difference vegetation index(NDVI)product were applied to construct the human settlement *** on the spatial regression relationship between human settlement index and energy consumption data.A 1-km resolution dataset of AHF of 12 selected cities in the eastern China was *** least-squares(OLS)model was applied to detect the mechanism of spatial patterns of *** showed that industrial emission in selected cities of the eastern China was accountable for 63%of the total *** emission in megacities,such as Tianjin,Jinan,Qingdao,and Hangzhou,was most *** increasing speed in most areas in the chosen cities was quite *** growth or extremely high growth of AHF were located in central downtown *** Beijing,Shanghai,Guangzhou,Jinan,Hangzhou,Changzhou,Zhaoqing,and Jiangmen,a single kernel of AHF was *** influencing factors showed that precipitation,temperature,elevation,normalized different vegetation index,gross domestic product,and urbanization level were positive with ***,this investigation implied that urbanization level and economic development level might dominate the increasing of AHF and the spatial heterogeneousness of *** urbanization level or economic development level resulted in high increasing speeds of *** findings provide a novel way to reconstruct of AHF and scientific supports for energy management strategy development.

关键词： anthropogenic heat flux(AHF) Defense Meteorological Program/Operational Linescan System(DMSP/OLS)data spatiotemporal variations influencing factors eastern China

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spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in China’s cities

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 74-86页

作者： Ruyu Xu Keliang Wang Zhuang Miao Lingxuan Sun School of Economics Ocean University of ChinaQingdao 266011China China Western Economic Research Center Southwestern University of Finance and EconomicsChengdu 611130China School of Economics and Management Southwest Petroleum UniversityChengdu 610500China

The promotion of energy efficiency(EE)helps address energy constraints and promote environmental *** study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)*** findings are:①China’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder China’s urban EE.③Four configurational promotion paths for enhancing China’s urban EE are identified,where among those paths population density is a core condition,while government intervention is *** study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in China.

关键词： Energy efficiency spatiotemporal variations Influencing factors Configurational promotion paths

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spatiotemporal variations of maximum seasonal freeze depth in 1950s–2007 over the Heihe River Basin, Northwest China

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Research in Cold and Arid Regions 2014年第3期6卷 209-218页

作者： QingFeng Wang TingJun Zhang State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute CAS College of Earth and Environmental Sciences Lanzhou University National Snow and Ice Data Center Cooperative Institute for Research in Environmental Sciences University of Colorado at Boulder80309 USA

Investigation on spatiotemporal variations of maximum seasonal freeze depth （MSFD） over the Heihe River Basin is of great importance for systematic understanding of regional climate and environmental change, ecological-hydrological processes, water resources assessment, construction and resource development. Based on soil and air temperatures at the meteorological stations of the China Meteorological Administration （CMA） over the Heihe River Basin, MSFDs time series are structured into a composite time series over the 1960-2007 period. Evaluating the averaged MSFD time series for 1960 2007 reveals a statistically significant trend of 4.0 cm/decade or a net change of-19.2 cm for the 48-year period over the basin. The MSFD had significantly negative correlation with mean annual air temperature （MAAT）, winter air temperature, mean annual ground surface temperature （MAGST）, degree days of thawing for the air （DDTa） as well as for the surface （DDTs）, and degree days of freezing for the surface （DDFs）. While there was significantly positive correlation between DDF,. and MSFD time series, MSFD was deeper and changed greatly in the Heihe River source area. It was shallower in the east-central basin and gradually deepened in other sections of the basin. The MSFD distribution pattern in 2003-2005 is consistent with that of averaged degree days of freezing for air （DDFa） in 1960-2007. However, the maximum of MSFD may not be accurate, because there is no long term observation data in the deep seasonally frozen ground regions near the lower boundary of permafrost. With increasing elevation, averaged DDFa increased at a rate of 51.6 ℃-day/100m, therefore, the MSFG and the date reaching MSFG became deeper and later, respectively.

关键词： spatiotemporal variations MSFD potential driving variables seasonally frozen ground Heihe River Basin

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Influence of cascade reservoirs on spatiotemporal variations of hydrogeochemistry in Jinsha River

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Water Science and Engineering 2021年第2期14卷 97-108页

作者： Qiu-sheng Yuan Pei-fang Wang Juan Chen Chao Wang Sheng Liu Xun Wang Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China

River hydrogeochemistry offers necessary guidance for effective water environmental ***,the influence of cascade reservoirs on river hydrogeochemistry remains *** this study,the Jinsha River,the headwaters of the Yangtze River of China,was selected to investigate the spatiotemporal variations of hydrogeochemistry after the construction of six cascade *** ions,total dissolved solids,electrical conductivity,and pH values of sampled water in the upper natural reaches and lower reservoir-regulated reaches were analyzed in both flood and dry *** results of Piper diagram and Gibbs plots showed that the hydrogeochemistry of the Jinsha River was naturally controlled by both evaporation-crystallization and carbonate weathering processes,but it was also artificially affected by *** impoundment of cascade reservoirs affected the hydrodynamic condition of the *** river flow in the flood season was reduced by approximately 24.5%,altering the proportions of water sources and leading to notable hydrogeochemical alterations in reservoir-regulated ***,river hydrogeochemistry generally remained unchanged in the dry season,owing to the insignificant effect of cascade reservoirs on river *** contrast to what has been observed in previous studies of individual reservoirs,the cumulative influence of cascade reservoirs on the Jinsha River flow regime did not cause abrupt hydrogeochemical changes between the upstream and downstream areas of each ***,the water quality assessments revealed that the impoundment of cascade reservoirs improved downstream irrigational water quality,with lower Naþratio values in the flood *** study provides the earliest evaluation of cascade reservoir influence on the hydrogeochemistry of the Jinsha *** findings of this study can be used as a reference for scientific guidelines for future environmental management of cascade reservoirs in large rivers.

关键词： River hydrogeochemistry spatiotemporal variations Controlling factors Cascade reservoirs Jinsha River

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spatiotemporal variations and driving factors of habitat quality in the loess hilly area of the Yellow River Basin:A case study of Lanzhou City,China

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Journal of Arid Land 2022年第6期14卷 637-652页

作者： DONG Jianhong ZHANG Zhibin LIU Benteng ZHANG Xinhong ZHANG Wenbin CHEN Long School of Design and Art Lanzhou University of TechnologyLanzhou 730050China School of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China

Rapid industrialization and urbanization have led to the most serious habitat degradation in China,especially in the loess hilly area of the Yellow River Basin,where the ecological environment is relatively *** contradiction between economic development and ecological environment protection has aroused widespread *** this study,we used the habitat quality of Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST-HQ)model at different scales to evaluate the dynamic evolution characteristics of habitat quality in Lanzhou City,Gansu Province of *** spatiotemporal variations of habitat quality were analyzed by spatial autocorrelation.A Geographical Detector(Geodetector)model was used to explore the driving factors that influencing the spatial differentiation of habitat quality,including natural factors,socio-economic factors,and ecological protection *** results showed that the habitat quality index of Lanzhou City decreased from 0.4638 to 0.4548 during *** areas with reduced the habitat quality index were mainly located in the Yellow River Basin and Qinwangchuan Basin,where are the main urban areas and the new economic development areas,*** spatial distribution of habitat quality presented a trend of high in the surrounding areas and low in the middle,and showed a significant positive spatial *** the increase of study scale,the spatial distribution of habitat quality changed from concentrated to *** spatial differentiation of habitat quality in the study area was the result of multiple *** them,topographic relief and slope were the key *** synergistic enhancement among these driving factors intensified the spatial differentiation of habitat *** findings of this study can provide a scientific basis for land resources utilization and ecosystem restoration in the arid and semi-arid land.

关键词： Habitat quality spatiotemporal variations driving factors InVEST-HQ model Geodetector model Lanzhou City Yellow River Basin

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Analysis of spatiotemporal variations in the characteristics of soil microbial communities in Castanopsis fargesii forests

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Journal of Forestry Research 2020年第5期31卷 1975-1984页

作者： Hongyong Qiao Yaning Luan Bing Wang Wei Dai Mengsai Zhao College of Forestry Beijing Forestry UniversityQinghua East Road No.35Haidian DistrictBeijing 100083People’s Republic of China Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing Summer Palace and the red flagHaidian DistrictBeijing 100091People’s Republic of China

Castanopsis fargesii is a good afforestation plants and various microorganisms play important roles in mediating the growth and ecological functions of this *** this study,we evaluated changes in microbial communities in soil samples from *** *** phospholipid fatty acid(PLFA)biomarker method was used to obtain bacteria,fungi,actinomycetes,gram-positive bacteria(G?),gram-negative bacteria(G-),aerobic bacteria,and anaerobic bacteria to investigate spatiotemporal changes in microbial communities during the growing *** results show that soil microorganisms were mainly concentrated in the upper 20-cm layer,demonstrating an obvious surface aggregation(P<0.05).Large amounts of litter and heavy rainfall during the early growing season resulted in the highest PLFA contents for various microorganisms,whereas relatively low and stable levels were observed during other *** dominant species during each period were bacteria.G+ or aerobic bacteria were the main bacterial populations,providing insights into the overall trends of soil bacterial PLFA *** to the relative accumulation of refractory substances during the later stages of litter decomposition,the effects of fungi increased ***,our findings demonstrate that the main factors influencing microbial communities were litter,rainfall,and soil field capacity.

关键词： Castanopsis fargesii Phospholipid fatty acids Soil microbial community spatiotemporal variations

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Eco-compensation in Guanting Reservoir Watershed Based on spatiotemporal variations of Water Yield and Purification Services

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Journal of Resources and Ecology 2018年第4期9卷 416-425页

作者： WEN Yihui LIU Guihuan WU Rui Chinese Academy for Environment Planning Beijing 100012China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China Urban Planning ＆ Design Institute of Shenzhen ShenzhenGuangdong 518000China

Guanting Reservoir（GR） is one of the most important water sources for Beijing and neighboring *** to water pollution,it was withdrawn from the system to supply Beijing drinking water;however,after a thorough treatment process,GR was made a reserve water source since *** develop a comprehensive and quantitative analysis of water yield and purification services in the GR watershed,this study selected two time periods：the period when GR was withdrawn from the system supplying local drinking water and the period that it has been designated a reserve water *** In VEST model was used to evaluate the quantities of water yields,and total nitrogen and total phosphorus outputs from 1995 to 2010 Additionally,the spatiotemporal variations of water yield services and water quality purification services in the GR watershed were *** results showed that water yield services in the GR watershed first weakened and then became stronger,but weakened overall during the years 1995 to *** yield capacity in the basin decreased from 1.89×10^9 m3 in 1995 to 1.43×10^9 m3 in 2010（a drop of 24.0% in total）.Water quality purification services also showed the same *** nitrogen output decreased from 4028.7 t in 1995 to 3611.4 t in 2010,while total phosphorus decreased from 379.7 t in 1995 to 354.0 t in *** and phosphorus purification services were enhanced by 10.4% and 6.8%,*** in the climate and land use were the main factors which lead to the changes in the water yield service in the GR *** intended to protect water resource have matched the varying trends of water quality purification services during different *** one hand,the research results provide a foundation to identify key fields for eco-compensation in the Guanting Reservoir *** another hand,the ecosystem service value will increase on the basis of eco-compensation criteria through setting the scenarios of returning farmland to forest and

关键词： GR watershed INVEST model spatiotemporal variations water quality purification water yield

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Occurrence,spatial and seasonal variation,and environmental risk of pharmaceutically active compounds in the Pearl River basin,South China

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 83-95页

作者： Haojun Lei Kaisheng Yao Bin Yang Lingtian Xie Guangguo Ying SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China School of Environment South China Normal UniversityGuangzhou 510006China Aquatic Ecology and Water Quality Management Group Wageningen University6700 AA WageningenNetherlands

The occurrence,fate,and environmental risk of 40 pharmaceutically active compounds(PhACs)from surface waters and sediments were comprehensively investigated in the Beijiang River,Xijiang River,and Maozhou River of the Pearl River basin,South *** acid and diclofenac(antiinflammatory drugs),gemfibrozil(a lipid regulator),carbamazepine(an antiepileptic drug),diazepam(a psychoactive drug),and 2-methyl-4-chloro-phenoxyacetic acid(MCPA,a pesticide)were the most ubiquitous compounds in the studied *** average concentrations of detected PhACs in surface waters and sediments ranged from 0.17 to 19.1 ng/L and 0.10 to 10.4 ng/g,***,PhACs concentration in surface waters and sediments varied greatly among and within the Beijiang River,Xijiang River,and Maozhou *** largest annual flux of PhACs of the Xijiang River and Beijiang River was more than 11000 kg per annum,whereas only 25.7 kg/a in the Maozhou *** addition,the estimated emissions of PhACs in the Beijiang River,Xijiang River,and Maozhou River ranged respectively from 0.28 to 4.22 kg/a,0.12 to 6.72 kg/a,and 6.66 to 91.0 kg/a,and the backestimated usage varied with a range from 12.0 to 293 kg/a,6.79 to 944 kg/a,368 to 17459 kg/***,the emissions of PhACs showed a close relationship with the gross domestic product(GDP)of each city along the Pearl *** environmental risk assessment suggested that diazepam and ibuprofen had a moderate risk in this region.

关键词： Pharmaceutically active compounds Occurrence spatiotemporal variations Pearl River Environmental risk assessment

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Occurrence and ecotoxicological risk assessment of pesticides in sediments of the Rosetta branch,Nile River, Egypt

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Journal of Environmental Sciences 2022年第8期34卷 21-31页

作者： Fawzy Eissa Mahmoud Al-Sisi Khaled Ghanem Environment and Bio-agriculture Department Faculty of AgricultureAl-Azhar UniversityNasr CityCairo 11884Egypt Central Laboratory of Residue Analysis of Pesticides and Heavy Metals in Food(QCAP) Agricultural Research CenterDokkiGiza 12311Egypt

This study aimed to(1) monitor the occurrence and spatiotemporal variations of 100 pesticides in sediments collected monthly from July 2018 to June 2019 from sampling sites in El-Rahawy, Sabal, and Tala, along the Rosetta branch of the Nile River, Egypt, and(2) perform an ecological risk assessment for aquatic organisms upon exposure to the detected sediment pesticides based on the risk quotient(RQ) method. Out of the 100 pesticides monitored, 16 pesticides belonging to seven chemical families were detected, and 55% of the sediment samples were contaminated with one or more pesticide residues. The mean concentration(mg/kg dry weight(dw)) and detection frequency(%) of the four most frequently detected pesticides in the sediment samples were as follows: chlorpyrifos(0.18 mg/kg dw and 34%), p,p-DDE(0.018 mg/kg dw and 30%), cypermethrin(0.03 mg/kg dw and 14%), and deltamethrin(0.026 mg/kg dw and 13%). The spatial distribution exhibited that El-Rahawy had the highest pesticide load(2.86 mg/kg dw) among the studied sites, whereas the temporal variations revealed that the highest total pesticide concentrations were detected in winter season(1.73 mg/kg dw). Meanwhile, 12 pesticides showed high RQs(>1), posing a potential ecological risk to aquatic species that live and feed on such sediments.

关键词： Pesticide residues Sediments spatiotemporal variations Risk quotient

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