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High-frequency climatic fluctuations over the past 30 ka in northwestern margin of the East Asian monsoon region, China

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Journal of Arid land 2022年第12期14卷 1331-1343页

作者： WU Huining CUI Qiaoyu Bailie School of Petroleum Engineering Lanzhou City UniversityLanzhou 730070China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Whether millennial-to centennial-scale climate variations throughout the Holocene convey universal climate change is still widely *** this study,we aimed to obtain a set of high-resolution multi-proxy data(1343 particle size samples,893 total organic carbon samples,and 711 pollen samples)from an alluvial-lacustrine-aeolian sequence based on an improved age-depth model in the northwestern margin of the East Asian monsoon region to explore the dynamics of climate changes over the past 30 *** revealed that the sequence not only documented the major climate events that corresponded well with those reported from the North Atlantic regions but also revealed many marked and high-frequency oscillations at the millennial-and ***,the late stage of the last glacial lasting from 30.1 to 18.1 *** BP was a dry and cold *** deglacial(18.1-11.5 *** BP)was a wetting(probably also warming)period,and three cold and dry excursions were found in the wetting trend,i.e.,the Oldest Dryas(18.1-15.8 *** BP),the Older Dryas(14.6-13.7 *** BP),and the Younger Dryas(12.5-11.5 *** BP).The Holocene can be divided into three portions:the warmest and wettest early portion from 11.5 to 6.7 *** BP,the dramatically cold and dry middle portion from 6.7 to 3.0 *** BP,and the coldest and driest late portion since 3.0 *** *** analysis results on the total pollen concentration revealed five substantially periodicities:c.5500,2200,900,380,and 210 *** the exception of the c.5500 a quasi-cycle that was causally associated with the Atlantic meridional overturning circulation,the other four quasi-cycles(i.e.,c.2200,900,380,and 210 a)were found to be indirectly causally associated with solar *** study provides considerable insight into the dynamic mechanism of the Asian climate on a long-time scale and future climatic change.

关键词： East Asian monsoon region total pollen concentrations climate periodicity millennial-centennial time scale Chinese Loess Plateau

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Eco-geographical Regionalization of China:An Approach Using the Rough Set Method

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Chinese Geographical Science 2022年第1期32卷 93-109页

作者： DENG Haoyu WU Shaohong YIN Yunhe GAO Jiangbo ZHAO Dongsheng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Eco-geographical regionalization involves dividing land into regions by considering both intra-regional consistency and interregional disparity and is based on the pattern of differentiation of eco-geographical *** to the complexity of the land surface,and the limitation of data and appropriate methods,regions in China have hitherto been mapped manually,meaning that the process of mapping was *** make the regionalization technique repeatable,this study aimed to extract and quantify the expert knowledge of regionalization using an automated *** rough set method was adopted to extract rules of regionalization based on the existing eco-geographical regionalization map of China,as well as its corresponding meteorological and geological ***,the rules for regionalization were obtained hierarchically for each natural domain,each temperature zone,and each humidity *** to differences in zonal differentiation,the rule extraction sequence for the eastern monsoon zone and Tibetan Alpine zone was temperature zone first followed by humidity region,with the reverse order being applied for the northwest arid/semi-arid *** show that the extracted indicators were similar to those of the existing(expert-produced)regionalization scheme but more *** primary indicator for defining temperature zones was the≥10℃ growing season,and the secondary indicators were the January and July mean *** primary and secondary indicators for identifying humid regions were aridity index and precipitation,***-geographical regions were mapped over China using these rules and the gridded *** the temperature zones and humidity regions mapped by the rules show≥85%consistency with the existing regionalization,which is higher than values for mapping by the commonly used simplified method that uses the classification of one *** study demonstrates that the proposed rough set method can establis

关键词： Eco-geographical regionalization boundary rough set China

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The summer standardized precipitation evapotranspiration index(SPEl)dataset for six European regions over the past millennium reconstructed by tree-ring chronologies

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Big Earth Data 2023年第4期7卷 1146-1168页

作者： Liang Zhang Yang Liu Jingyun Zheng Zhixin Hao Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Accurate reconstructed series are crucial for studying the differences in regional hydroclimatic variations in Europe over the past *** hierarchical clustering analysis and stepwise regression methods,we reconstructed yearly time series of the summer standardized precipitation evapotranspiration index(SPEl)for six European regions over the past *** analysis also revealed prominent regional hydroclimatic differences in multidecadal signals over the past 500 *** instance,in the 1500s-1570s(from the beginning of the 1500s to the end of the 1570s),drying trends were observed in northern and southeastern Europe,whereas southwestern Europe experienced a wetting ***,drying trends were observed in northern and central Europe in the ***,wetting trends were observed in western and central Europe during the 1830s-1850s,with drying trends in northern and southeastern ***,the hydroclimatic variations in most European regions showed drying trends in the 1920s-1950s,especially in southern *** utilizing large amounts of tree-ring samples and directly comparing regional hydroclimatic variations,our reconstructions provide a consistent and comprehensive dataset for further *** reconstructed dataset is available at https://***/10.57760/sciencedb.07215.

关键词： Europe hydroclimatic variations regional reconstruction tree-ring chronologies past millennium

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Divergent effects of climate change on cropland ecosystem water use efficiency at different elevations in southwestern China

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Journal of Geographical Sciences 2022年第8期32卷 1601-1614页

作者： TAO Jian ZHU Juntao ZHANG Yangjian DONG Jinwei ZHANG Xianzhou School of Public Administratio n Shand ong Tech no logy and Business UniversityYantai 264005ShandongChina Nagqu Alpine Grassland Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

Understanding climatic effects on cropland water use efficiency at different elevations is imperative for managing agricultural water and production in response to ongoing climate change in climate-sensitive areas with complex topography, such as southwestern China. We investigated climatic effects on cropland water use efficiency in southwestern China at each 100-m elevation bin during 2001–2017. The maximum water use efficiency was 1.71 gC kg^(–1) H_2O for the 1900–1999 m elevation bin under the growing season temperature and precipitation of 14.58±0.32℃ and 965.40±136.45 mm, respectively. The water use efficiency slopes were dominated by the evapotranspiration slopes at elevations below 1999 m but were controlled by the gross primary productivity slopes at elevations above 2000 m. This difference was caused by the substantial responses of evaporation to climate change at lower elevations and the increased climatic sensitivity of gross primary productivity at higher elevations. In comparison to those at other elevations, croplands at lower elevations were more vulnerable to extreme drought because of the dominant role fluctuating evapotranspiration played in water use efficiency. The findings will improve cropland water management in the study area.

关键词： cropland water use efficiency southwestern China elevational gradient

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Microbial responses towards biochar application in potentially toxic element(PTE)contaminated soil:a critical review on effects and potential mechanisms

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Biochar 2023年第1期5卷 993-1013页

作者： Xiao Yang Miao You Siyan Liu Binoy Sarkar Zhaoshu Liu Xiulan Yan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Future Industries Institute University of South AustraliaMawson LakesSA 5095Australia

Soil harbors a huge diversity of microorganisms and serves as the ecological and social foundation of human ***,soil health management is of utmost and consistent importance,aligning with the United Nations Sustainable Development *** of the most hazardous contaminants in soil matrix is potentially toxic elements(PTEs),which can cause stress in soil indigenous microorganisms and severely jeopardize soil *** technology has emerged as a promising means to alleviate PTE toxicity and benefit soil health *** literature has broadly integrated knowledge about the potential consequences of biochar-amended soil but has focused more on the physical and chemical responses of the soil system than microbiological *** consideration of the indispensable roles of soil microbials,this paper first introduces PTE-induced stresses on soil microbials and then proposes the mechanisms of biochar’s effects on soil ***,microbial responses including variations in abundance,interspecific relationships,community composition and biological functions in biochar-amended soil are critically *** review thus aims to provide a comprehensive scientific view on the effect of biochar on soil microbiological health and its management.

关键词： Soil microbiological health Biogeochemistry Potential toxic elements Biochar Environmental impact assessment

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The relationship between interannual dry/wet changes and nomadic wars in the Hexi Corridor region of China during the period 241–1912 A.D.

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Science China Earth Sciences 2024年第6期67卷 1922-1931页

作者： Fei TANG Zhilin SHI Qinhua TIAN Xiaogang DU Yong ZHANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Institute of Dunhuang Studies Lanzhou UniversityLanzhou 730020China National Climate Center China Meteorological AdministrationBeijing 100081China Longchanghe Station Gansu Qilian Mountain National Nature ReserveZhangye 734400China University of Chinese Academy of Sciences Beijing 100049China

The link between climate and war has long been a topic of great scientific and social *** this study,we investigate the influence of climate on warfare in China’s Hexi Corridor region since 241 *** the superposed epoch analysis of tree-ring data and historical war data,we observe a notable correlation between interannual dry-wet variations and wars instigated by nomadic groups in the Hexi ***,this relationship is dynamic and influenced by the region’s relative *** periods in which the Hexi Corridor was ruled by multiple regimes,wars tended to follow dry climatic conditions,which may be due to the fact that unusual drought during these periods likely heightened competition for resources and ***,during times of regional unity,wars were more likely to occur when climatic conditions were wet because the expansion of rangelands and the accumulation of resources helped fuel the nomads’outward *** findings underscore the complexity of the relationship between war and climate *** gain a more comprehensive understanding of this relationship,continuous,high-resolution historical temperature and humidity datasets with broader and more uniform coverage are needed across multiple *** addition,collecting and examining disaggregated historical war data for regions with distinct characteristics is essential.

关键词： Drought Interannual dry and wet variations War The Hexi Corridor Tree ring Nomadic groups

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China's agricultural land use change and its underlying drivers:A literature review

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Journal of Geographical Sciences 2021年第8期31卷 1222-1242页

作者： WANG Xue LI Xiubin Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Understanding the manifestations and underlying drivers of agricultural land use change in China is of great importance for both domestic and global food security. However, little is known about the holistic pattern of agricultural land use change across China, especially from the perspective of intensity since the evidence has been gathered mainly through case studies at local levels. This study conducts a systemic review of agricultural land use change and its underlying drivers in China by aggregating 169 relevant case studies from 123 publications. The cases related to intensification and disintensification, which are the two types of agricultural land use change, are generally equal, accounting for 50% of the total number of cases. Intensification and disintensification can be further divided into the same three categories: expansion/contraction of agricultural land, changes in agricultural land use activities and changes in land management intensity. Demographic, economic, technological, and institutional drivers, together with location factors, are frequently noted as significant underlying drivers, while sociocultural drivers and farm(er) characteristics are less frequently recognized. Finally, three major land use change trajectories are summarized mainly concerning rising labor costs and the concomitant increase in off-farm employment, the ecological improvement policy, and advances in agricultural technology.

关键词： agricultural land land use intensity driving forces aggregate analysis China

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Changes and determining factors of crop evapotranspiration derived from satellite-based dual crop coefficients in North China Plain

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The Crop Journal 2022年第5期10卷 1496-1506页

作者： Qinghua Tan Yujie Liu Tao Pan Xianfang Song Xiaoyan Li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Evaluating actual crop evapotranspiration(ET) variations and their determining factors under changing climates is crucial for agricultural irrigation management and crop productivity improvement in nonhumid *** study analyzed the spatiotemporal characteristics and detected the determining factors of ETfor winter wheat and summer maize rotation system from 2000 to 2017 in the North China Plain(NCP),by combining the FAO-56 dual crop coefficient approach with remotely sensed vegetation indices(VIs).The results indicated that daily air temperature increased in varying degrees while wind speed and sunshine hours decreased slightly during the growing season of winter wheat and summer maize over the study *** trends of relative humidity and effective precipitation varied in crop growing *** on the validated relationship of dual crop coefficients and VIs,the estimated multi-year average ETof winter wheat(370.29±31.28 mm) was much higher than summer maize(281.85±20.14 mm),and the rotation cycle was 652.43±27.67 *** ETof winter wheat and the rotation cycle increased by 2.96 mm aand 1,77 mm a,***,the ETof summer maize decreased with distinct spatial ***,winter wheat ETincreased significantly in the northeast NCP,covering the Beijing-Tianiin-Hebei ***,significant increases in summer maize ETwere detected in the southwest *** sensitivity and contribution analysis showed that ETof winter wheat and summer maize was positively sensitive to temperature,wind speed,and sunshine hours while negatively to relative ***,wind speed and sunshine hours contributed most to changes in ET(around 20%-40%).

关键词： Actual crop evapotranspiration Determining factor North China Plain Rotation system Spatiotemporal variation

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西藏羊卓雍错湖面水热通量变化及其与气象因子的关联

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Journal of Geographical Sciences 2024年第2期34卷 397-414页

作者：张雪芹靳铮沈鹏珂郑度 Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China National Climate Center China Meteorological AdministrationBeijing 100081China

Lake surface water-heat exchange and its climatic attribution critically influence alpine lakes’evaporation mechanism and water storage balance with climate ***,this paper first explored the hourly,daily,and monthly water-heat flux variations of the lake surface and their correlations with meteorological factors based on the eddy covariance turbulent flux observation over the Yamzhog Yumco,an alpine lake in south Tibet in the non-freezing period(April-December)in 2016 and *** found that the average latent heat flux was much higher than the sensible heat flux on the lake surface from April to ***,the water-heat flux exhibited remarkable seasonal variation,with a prominent role of higher air temperature and humidity in summer jointly controlling the lake-air energy ***,the main controlling meteorological factors for the water-heat flux variation of the lake surface differed with diversified ***,the lake-air temperature difference was the most significant meteorological factor related to sensible heat flux on the half-hourly,daily,and monthly ***,the latent heat flux was strongly positively correlated with wind speed and the synergies of wind speed and water vapor pressure deficit on the daily and half-hourly ***,the lake surface heat flux was significantly negatively correlated with net radiation flux on the daily and monthly *** negative correlation can be attributed to the seasonal variation of the water surface net radiation,and the phase difference in heat flux intensity caused by the lake-air temperature difference and heat capacity *** findings will hopefully improve the understanding of energy exchange and evaporation mechanisms for alpine lakes in a warming climate.

关键词： lake surface water-heat flux meteorological factor eddy covariance alpine lakes Yamzhog

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Incorporating Exercise Efficiency to Evaluate the Accessibility and Capacity of Medical Resources in Tibet, China

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Chinese Geographical Science 2023年第1期33卷 175-188页

作者： WANG Li YANG Linsheng WEI Binggan LI Hairong CAI Hongyan HUANG Jixia YUAN Xing Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Resources and Environmental Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China

Accessibility and capacity of medical resources are key for the health care and emergency response, while the efficiency of the medical resources is very much limited by hypoxia in Tibet, *** introducing exercise efficiency, this study explores the accessibility of township residence to county-ship medical resources in Tibet using weighted mean travel time(WMT), and evaluates the medical capacity *** results show that: 1) the average travel time of township residence to county-level hospital is around2 h by motor vehicle in *** than half of the population can not reach the county-ship hospital within 1 h, 33.24% of the population can not reach within 2 h, and 3.75% of the population can not reach within 6 h.2) When considering the catchment of the medical resources and the population size, the WMT of the county-ship medical resources ranges from 0.25 h to 10.92 h.3) After adjusted by travel time and exercise efficiency, the county-ship medical capacity became more unequal, with 38 out of 74 counties could not meet the national guideline of 1.8 medical beds per 1000.4) In total, there are 17 counties with good WMT and sufficient medical resources,while 13 counties having very high WMT and low capacity of medical resources in *** the end, suggestions on medical resources relocation and to improve the capacity are *** study provides a method to incorporate exercise efficiency to access the accessibility and evaluate medical capacity that can be applied in high altitude ranges.

关键词： exercise efficiency medical resources medical capacity Tibet

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