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spatial-temporal characteristics and influencing factors of relative humidity in arid region of Northwest China during 1966–2017

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Journal of Arid Land 2020年第3期12卷 397-412页

作者： CHEN Ditao LIU Wenjiang HUANG Farong LI Qian Friday UCHENNAOCHEGE LI Lanhai State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Ili Station for Watershed Ecosystem Research Chinese Academy of SciencesXinyuan 835800China University of Chinese Academy of Sciences Beijing 100049China CAS Research Center for Ecology and Environment in Central Asia Urumqi 830011China Department of Geography and Environmental Management University of Port HarcourtPort Harcount 500102Nigeria Xinjiang Regional Center of Resources and Environmental Science Instrument Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China

Playing an important role in global warming and plant growth,relative humidity(RH)has profound impacts on production and living,and can be used as an integrated indicator for evaluating the wet-dry conditions in the arid and semi-arid ***,information on the spatial-temporal variation and the influencing factors of RH in these regions is still *** study attempted to use daily meteorological data during 1966–2017 to reveal the spatial-temporal characteristics of RH in the arid region of Northwest China through rotated empirical orthogonal function and statistical analysis method,and the path analysis was used to clarify the impact of temperature(T),precipitation(P),actual evapotranspiration(ETa),wind speed(W)and sunshine duration(S)on *** results demonstrated that climatic conditions in North Xinjiang(NXJ)was more humid than those in Hexi Corridor(HXC)and South Xinjiang(SXJ).RH had a less significant downtrend in NXJ than that in HXC,but an increasingly rising trend was observed in SXJ during the last five decades,implying that HXC and NXJ were under the process of droughts,while SXJ was getting *** was a turning point for the trend of RH in Xinjiang,which occurred in *** analysis indicated that RH was negatively correlated to T,ETa,W and S,but it increased with increase of P.S,T and W had the greatest direct effects on RH in HXC,NXJ and SXJ,*** was the factor which had the greatest indirect effect on RH in HXC and NXJ,while T was the dominant factor in SXJ.

关键词： relative humidity spatial-temporal characteristics path analysis influencing factor arid region

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spatial-temporal characteristics of lake area variations in Hoh Xil region from 1970 to 2011

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Journal of Geographical Sciences 2014年第4期24卷 689-702页

作者： YAO Xiaojun LIU Shiyin LI Long SUN Meiping LUO Jing College of Geography and Environment Sciences Northwest Normal University Lanzhou 730070 China State Key Laboratory of Cryosphere Sciences Cold and Arid Regions Environmental and Engineering Re search Institute. CAS. Lanzhou 730000. China

As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970s and Landsat TM/ETM＋ remote sensing images iin the 1990s and the period from 2000 to 2011, the data of 83 lakes with an area above 10 km2 each were obtained by digitization method and artificial visual interpretation technology, and the causes for lake variations were also analyzed. Some conclusions can be drawn as follows. （1） From the 1970s to 2011, the lakes in the Hoh Xil region firstly shrank and then expanded, in particular, the area of lakes generally decreased during the 1970s-1990s. Then the lakes expanded from the 1990s to 2000 and the area was slightly higher than that in the 1970s. The area of lakes dramatically increased after 2000. （2） From 2000 to 2011, the lakes with different area ranks in the Hoh Xil region showed an overall expansion trend. Meanwhile, some regional differences were also discovered. Most of the lakes expanded and were widely distributed in the northern, central and western parts of the region. Some lakes were merged together or overflowed due to their rapid expansion. A small number of lakes with the trend of area decrease or strong fluctuation were scattered in the central and southern parts of the study area. And their variations were related to their own supply conditions or hydraulic connection with the downstream lakes or rivers. （3） The increase in precipitation was the dominant factor resulting in the expansion of lakes in the Hoh Xil region. The secondary factor was the increase in meltwater from glaciers and frozen soil due to climate warming.

关键词： lake variation spatial-temporal characteristics Hoh Xil region Tibetan Plateau

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spatial-temporal characteristics of PM_(2.5) in China:A city-level perspective analysis

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Journal of Geographical Sciences 2016年第11期26卷 1519-1532页

作者：方创琳王振波许光 Xinjiang University Institute of Geographic Sciences and Natural Resources Research CAS

Haze pollution has become a severe environmental problem in the daily life of the people in China. PM2.s makes a significant contribution to poor air quality. The spatio-temporal features of China＇s PM2.s concentrations should be investigated. This paper, based on ob- served data from 945 newly located monitoring sites in 2014 and industrial working population data obtained from International Standard Industrial Classification （ISIC）, reveals the spa- tio-temporal variations of PM2.5 concentrations in China and the correlations among different industries. We tested the spatial autocorrelation of PM2.5 concentrations in the cities of China with the spatial autocorrelation model. A correlation coefficient to examine the correlativity of PM2.5 concentrations and 23 characteristic variables for 190 cities in China in 2014, from which the most important ones were chosen, and then a regression model was built to further reveal the social and economic factors affecting PMg.g concentrations. Results：（1） The Hu Huanyong Line and the Yangtze River were the E-W divide and S-N divide between high and low values of China. （2） The PM2.5 concentrations shows great seasonal variation, which is high in autumn and winter but low in spring and summer. The monthly average shows a U-shaped pattern, and daily average presents a periodic and impulse-shaped change. （3） PM2.5 concentrations had a distinct characteristic of spatial agglomeration. The North China Plain was the predominant region of agglomeration, and the southeastern coastal area had stable good air quality.

关键词： PM2.5 China spatial-temporal characteristics monitoring data

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Research on spatial-temporal characteristics and Driving Factor of Agricultural Carbon Emissions in China

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Journal of Integrative Agriculture 2014年第6期13卷 1393-1403页

作者： TIAN Yun ZHANG Jun-biao HE Ya-ya College of Economics & Management Huazhong Agricultural University Hubei Rural Development Research Center Huazhong Agricultural University

Macroscopic grasp of agricultural carbon emissions status, spatial-temporal characteristics as well as driving factors are the basic premise in further research on China’s agricultural carbon emissions. Based on 23 kinds of major carbon emission sources including agricultural materials inputs, paddy ifeld, soil and livestock breeding, this paper ifrstly calculated agricultural carbon emissions from 1995 to 2010, as well as 31 provinces and cities in 2010 in China. We then made a decomposed analysis to the driving factors of carbon emissions with logarithmic mean Divisia index （LMDI） model. The results show：（1） The amount of agricultural carbon emissions is 291.1691 million t in 2010. Compared with 249.5239 million t in 1995, it increased by 16.69%, in which, agricultural materials inputs, paddy ifeld, soil, enteric fermentation, and manure management accounted for 33.59, 22.03, 7.46, 17.53 and 19.39%of total agricultural carbon emissions, respectively. Although the amount exist ups and downs, it shows an overall trend of cyclical rise; （2） There is an obvious difference among regions：the amount of agricultural carbon emissions from top ten zones account for 56.68%, while 9.84%from last 10 zones. The traditional agricultural provinces, especially the major crop production areas are the main source regions. Based on the differences of carbon emission rations, 31 provinces and cities are divided into ifve types, namely agricultural materials dominant type, paddy ifeld dominant type, enteric fermentation dominant type, composite factors dominant type and balanced type. The agricultural carbon emissions intensity in west of China is the highest, followed by the central region, and the east zone is the lowest; （3） Compared with 1995, efifciency, labor and structure factors cut down carbon emissions by 65.78, 27.51 and 3.19%, respectively;while economy factor increase carbon emissions by 113.16%.

关键词： China agricultural carbon emissions spatial-temporal characteristics driving factor LMDI model

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spatial-temporal characteristics of chlorophyll a concentration in the Sanya Bay of China

Spatial-temporal characteristics of chlorophyll a concentrat...

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2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： C.Y.Shen South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China Guangdong Ocean University Zhanjiang China Graduate School of Chinese Academy of Sciences Beijing China P.Shi Q.G.Xing S.Z.Liang M.J.Li Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai China J. D. Dong South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

The present study investigated the spatial-temporal characteristics of chlorophyll a （chl-a） concentration in Sanya Bay by shipboard survey data at 12 stations from 2006 to 2008,and discussed the relationship between chl-a distribution and influential factors using MODIS sea surface temperature （SST）,sea surface wind （SSW） and rainwater runoff data. Results showed that the chl-a concentration in Sanya Bay ranged from 0.30 to 13.58 mg·m-3,the average concentration and standard deviation （SD） were 1.49 mg·m-3 and 1.74 mg·m-3 respectively. The chl-a showed a decreased tendency from estuary to offshore,and a decreased trends with the depth increased in the estuary of Sanya River,whereas indicated increased trends in the area offshore. In the river mouth,the relative higher value appeared in autumn. But in the zone offshore,the relative lower value appeared in spring. Summer had a obvious stratification vertically. This changes were associated with environmental factors changes in this area,such as the seasonal monsoon and nutrients from rainfall runoff.

关键词： spatial-temporal characteristics chlorophylla Sanya Bay MODIS SST QuikScat Wind

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A spatial-temporal DISTRIBUTION characteristics STUDY ON THE ATMOSPHERIC CARBON DIOXIDE OBSERVED BY GOSAT SATELLITE REMOTE SENSING

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Journal of Tropical Meteorology 2015年第4期21卷 408-416页

作者：刘瑞霞张兴赢刘杰刘雅各 Key Laboratory of Radiometric Calibration and Validation for Environmental Satellite China Meteorological AdministrationNational Satellite Meteorological Center China Meteorological Press Nanjing University of Information Science and Technology

The variation of the atmospheric Carbon Dioxide （CO2） concentration plays an important role in global cli- mate and agriculture. We analyzed the spatial-temporal characteristics of CO2 in the China region and around the globe with the CO2 column mixing ratios observed by the Japanese GOSAT satellite （Greenhouse Gases Observing Satellite）. In order to make sure that the accuracy of the CO2 data retrieved by the satellite meets the needs of the climate charac- teristics analyses, we ran a validation on the CO2 column mixing ratios retrieved by the satellite against the ground-based TCCON （Total Carbon Column Observing Network） observation data. The result shows that the two sets of data have a correlation coefficient of higher than 0.7, and a bias of within 2.2 ppmv. Therefore, the GOSAT CO2 da- ta can be used for the climate characteristics analysis of global CO2. Our analysis on the spatial-temporal characteristics of the CO2 column mixing ratios observed during the period of June 2009 through January 2014 proved that, with the impact of the natural emission of near ground CO2 and human activities, the global CO2 concentration has a significant latitudinal characteristics with its highest level averaging 390 oomv in the 0-40？N latitudinal zone in the Northern Hemisphere, and 387 ppmv in the Southern Hemisphere. China has a relatively higher CO2 concentration with the highest level exceeding 398 ppmv, and the eastern area higher than the western area. The variation of global CO2 concentration shows a seasonal pattern, i.e. the CO2 concen- tration reaches its highest in spring in the Northern Hemisphere averaging more than 392 ppmv, second highest in win- ter, and lowest in summer averaging less than 387 ppmv. It fluctuates the most in the Northern Hemisphere with an av- erage concentration of 392.5 ppmv in April, and 385.5 ppmv in July. While in the Southern Hemisphere, the seasonal fluctuation is smaller with the highest concentration occurring in July. Over th

关键词： GOSAT CO2 spatial-temporal characteristics validation

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Analysis on the temporal and spatial characteristics and Causes of Cold Wave in Qinhuangdao

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Meteorological and Environmental Research 2011年第5期2卷 12-15页

作者： ZHAO Ming,FAN Qin-hua,ZHAN Li-gang,ZHANG Xue-yang Qinhuangdao Meteorological Bureau in Hebei Province,Qinhuangdao 066000,China

[Objective] The aim was to study the temporal and spatial characteristics and causes of cold wave in Qinhuangdao.[Method] Based on temperature data from five surface meteorological stations in Qinhuangdao from 1970 to 2009 and the latest standards issuing cold wave early warning signal,statistical analysis on the temporal and spatial distribution of cold wave was carried out,and the causes were discussed preliminarily.[Result] From 1970 to 2009,the frequencies of blue and yellow cold wave in Qinhuangdao region were 2 334 and 105 times respectively,and cold wave occurred most frequently in Qinglong County and least frequently in Lulong County,which was related to the effects of underlying surface,latitude and *** wave might happen from September to next May,and the earliest occurrence date was September 9,while the latest end date was May *** addition,the frequency of cold wave was the highest in January and lowest in *** 1970 to 2009,blue cold wave occurred most frequently in 1972 and 1979 and least frequently in 1984,while the frequency of yellow cold wave was the highest in 1979 and lowest in 9 *** decadal variation,cold wave appeared most frequently in the 1970s and least frequently in the *** the increase of temperature,the frequency of cold wave showed decrease trend,and the beginning date tended to postpone,while its end date advanced,and it showed that the changes of cold wave was mainly caused by climate warming.[Conclusion] The study could provide theoretical guidance for the meteorological disaster prevention and reduction and local agricultural service.

关键词： Cold wave spatial-temporal characteristics Genetic analysis Qinhuangdao China

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Daily SPEI Reveals Long-term Change in Drought characteristics in Southwest China

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Chinese Geographical Science 2018年第4期28卷 680-693页

作者： JIA Yanqing ZHANG Bo MA Bin College of Geography and Environmental Science Northwest Normal University Department of Geography Xinzhou Normal University

Drought is the most widespread and insidious natural hazard, presenting serious challenges to ecosystems and human society. The daily Standardized Precipitation Evapotranspiration Index(SPEI) has been developed to identify the regional spatiotemporal characteristics of drought conditions from 1960 to 2016, revealing the variability in drought characteristics across Southwest China. Daily data from142 meteorological stations across the region were used to calculate the daily SPEI at the annual and seasonal time scale. The Mann-Kendall test and the trend statistics were then applied to quantify the significance of drought trends, with the following results. 1) The regionally averaged intensity and duration of all-drought and severe drought showed increasing trends, while the intensity and duration of extreme drought exhibited decreasing trends. 2) Mixed(increasing/decreasing) trends were detected, in terms of intensity and duration, in the three types of drought events. In general, no evidence of significant trends(P < 0.05) was detected in the drought intensity and duration over the last 55 years at the annual timescale. Seasonally, spring was characterized by a severe drought trend for all drought and severe drought conditions, while extreme drought events in spring and summer were very severe. All drought intensities and durations showed an increasing trend across most regions, except in the northwestern parts of Sichuan Province. However, the areal extent of regions suffering increasing trends in severe and extreme drought became relatively smaller. 3) We identified the following drought hotspots: Guangxi Zhuang Autonomous Region from the 1960 s to the 1990 s, respectively. Guangxi Zhuang Autonomous Region and Guizhou Province in the 1970 s and 1980 s, and Yunnan Province in the 2000 s. Finally, this paper can benefit operational drought characterization with a day-to-day drought monitoring index, enabling a more risk-based drought management strategy in the conte

关键词： drought spatial-temporal characteristics variability daily Standardized Precipitation Evapotranspiration Index (SPEI) Southwest China

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Spatio-temporal characteristics and influencing factors of urban floating population in China from 2011 to 2015

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Chinese Journal of Population,Resources and Environment 2019年第4期17卷 359-373页

作者： Lucang Wang Caixia Xue College of Geography and Environmental Sciences Northwest Normal UniversityLanzhouChina

Although China’s urban floating population is mainly concentrated in developed cities,from the central and western cities to the eastern developed cities,but the characteristics of the floating population in different cities are significantly *** paper systematically investigates the spatiotemporal characteristics and influencing factors of the floating population in different levels of *** results show that the regional imbalance to further strengthen,accumulation and dispersion trend has become increasingly obvious,liquidity is positively correlated and city level scale,and urban agglomeration and the core city is still polarization center of floating *** range is closely related to urban hierarchy:the higher the intra-urban grade,the more tend to inter-provincial flow;the lower the city grade,the more tend to intra-urban ***-term(1-2 years)and long-term(more than 7 years)flow-time *** short-term liquidity increases with the city grade,and the long-term liquidity decreases with the city *** are still the main body of the floating *** age,lower education level,low-skilled,high gender ratio employees are the most basic demographic characteristics of the floating population,although there are differences between different *** main reason for affecting the floating population is seeking jobs and doing business.

关键词： Urban floating population spatial-temporal characteristics demographic characteristics dynamic monitoring data China

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雍正朝慈善组织的时空特征及运作实况初探

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明清史 2015年第10期 148-156页

作者：王大学

雍正之前清代慈善组织最多的省份是江苏和浙江，雍正朝结束时善堂数量最多的是山东、河南，雍正朝慈善组织增长速度最快的是山东、河南、山西和福建。山西、福建大规模建设善堂多在雍正二年且后来被皇帝叫停，雍正十一年之后河南、山东... 详细信息

雍正之前清代慈善组织最多的省份是江苏和浙江，雍正朝结束时善堂数量最多的是山东、河南，雍正朝慈善组织增长速度最快的是山东、河南、山西和福建。山西、福建大规模建设善堂多在雍正二年且后来被皇帝叫停，雍正十一年之后河南、山东慈善组织建设在官方强力影响下因救荒需要而直达顶峰，这是雍正朝慈善史主要时空特征。山东慈善组织空间分布相对平均，河南善堂空间差异明显。河南设置善堂的州县仅占三分之二，部分慈善组织具有综合性善堂性质，部分普济类善堂安置流民，部分善堂运作理念具有明显儒家道德诉求。这些特征不仅说明雍正朝普济堂建设的理念和功能实态，还为全面了解此后普济堂发展轨迹以及部分善举思想来源提供新起点。

关键词：慈善组织时空特征运作实况雍正朝 charity spatial-temporal characteristics actually conditions of operate the emperor Yongzheng

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