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spatial and temporal variations of water quality in Cao-E River of eastern China

Journal of Environmental Sciences 2006年第4期18卷 680-688页

作者： CHEN Ding-jiang LU Jun YUAN Shao-feng JIN Shu-quan SHEN Ye-na Ministry of Education Key Lab of Environment Remediation and Ecological Health. Zhejiang University Hangzhou 310029 China Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 China

Evaluation and analysis of water quality variations were performed with integrated consideration of water quality parameters, hydrological-meteorologic and anthropogenic factors in Cao-E River, Zhejiang Province of China. Cao-E River system has been polluted and the water quality of some reaches are inferior to Grade V according to National Surface Water Quality Standard of China （GB2002）. However, mainly polluted indices of each tributary and mainstream are different. Total nitrogen （TN） and total phosphorus （TP） in the water are the main polluted indices for mainstream that varies from 1.52 to 45.85 mg/L and 0.02 to 4.02 mg/L, respectively. TN is the main polluted indices for Sub-watershed Ⅰ, Ⅱ, Ⅳ and Ⅴ（0.76 to 18.27 mg/L）. BOD5 （0.36 to 289.5 mg/L）, CODMn （0.47 to 78.86 mg/L）, TN （0.74 to 31.09 mg/L） and TP （0 to 3.75 mg/L） are the main polluted indices for Sub-watershed Ⅲ. There are tow pollution types along the river including nonpoint source pollution and point source pollution types. Remarkably temporal variations with a few spatial variations occur in nonpoint pollution type reaches （including mainstream, Sub-watershed Ⅰ and Ⅱ） that mainly drained by arable field and/or dispersive rural dwelling district, and the maximum pollutant concentration appears in flooding seasons. It implied that the runoff increases the pollutant concentration of the water in the nonpoint pollution type reaches. On the other hand, remarkably spatial variations occur in the point pollution type reaches （include Sub-watershed Ⅲ, Ⅳ and Ⅴ） and the maximum pollutant concentration appears in urban reaches. The runoff always decreases the pollutant concentration of the river water in the seriously polluted reaches that drained by industrial point sewage. But for the point pollution reaches resulted from centralized town domestic sewage pipeline and from frequent shipping and digging sands, rainfall always increased the concentration of pollutant （TN） in the river water too. Pollution cont

关键词： spatial and temporal variations water quality point pollution nonpoint pollution Cao-E River

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spatial and temporal variations of Synechococcus and picoeukaryotes in the Taiwan Strait,China

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Chinese Journal of Oceanology and Limnology 2009年第1期27卷 22-30页

作者：黄邦钦林学举洪华生 State Key Laboratory of Marine Environmental Science and Environmental Science Research Center Xiamen University

The size-fractionated phytoplankton biomass, and the spatial and temporal variations in abundance of Synechococcus (SYN) and picoeukaryotes (PEUK) were measured in the Taiwan Strait during three cruises (August 1997, February-March 1998, and August 1998). The results show that picophytoplankton and nanophytoplankton dominate the phytoplankton biomass, in average of 38% and 40%, respectively. SYN and PEUK varied over time in abundance and carbon biomass, greater in summer than in winter, in range of (7.70–209.2)×106 and (0.75–15.4)×106 cells/cm2 in the abundance, and 1.93–52.3 and 1.57–32.4 μgC/cm2 in the carbon biomass, for SYN and PEUK, respectively. The horizontal distributions of both groups were diurnal but heterogeneous in abundance, depending on the groups and layer of depths. Temperature is the key controlling factor for picophytoplankton distribution (especially in winter) in the Strait.

关键词： Synechococcus picoeukaryotes picophytoplankton spatial and temporal variations theTaiwan Strait

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spatial and temporal variations of Atmospheric Angular Momentum and Its Relation to the Earth Length of Day

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Journal of Meteorological Research 2014年第1期28卷 150-161页

作者：杨萍石文静肖子牛董仕任菊章 China Meteorological Administration Training Center Institute of Meteorological Science and Technology Yunnan Meteorological Bureau

The characteristics of atmospheric-angular-momentum （AAM） and length-of-day （LOD） on different timescales are investigated in this paper, on the basis of the NECP/NCAR reanalysis data and an LOD dataset for 1962-2010. The variation and overall trend of the AAM anomaly （AAMA） at different latitudes are presented, and the relationship between AAMA and LOD is discussed. The AAMAs in different latitude regions exhibit different patterns of variation, and the AAMA in the tropics makes a dominant contribution to the global AAMA. In the tropics, the AAMA propagates poleward to the extratropical regions. It is confirmed that a downward propagation of the AAMA occurs in the lower stratosphere. Correlation analysis shows that the relationship between AAMA and LOD varies significantly on different timescales. Specifically, the tropical AAMA is positively correlated with LOD on short timescales, but they are not obviously correlated on long timescales. This indicates that the interaction between AAM and the earth＇s angular momentum follows the conservative restriction on short timescales, but the influence of the earth angular momentum on that of the atmosphere depends on the interaction process on long timescales.

关键词： atmospheric angular momentum spatial and temporal variations propagation characteristics length of day

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spatial and temporal variations in pH and total alkalinity at the beginning of the rainy season in the Changjiang Estuary, China

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Acta Oceanologica Sinica 2005年第5期 72-81页

作者： GAO Xuelu1, 2, 3, SONG Jinming1*, LI Xuegang1, YUAN Huamao1, LI Ning1, 31. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China2. South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China3. Graduate School of Chinese Academy of Sciences, Beijing 100039, China

The results of field observation carried out in May 2003 were used to examine pH and total alkalinity behaviors in the Changjiang Estuary. It was showed that pH and total alkalinity took on clear spatial variations in values with the minima in the low salinity region. Like salinity, transect distributions of pH and total alkalinity (TA) in a downriver direction had a sharp gradient each. These gradients appeared in such a sequence that the TA gradient was earlier than salinity and pH gradients, and the salinity gradient was earlier than the pH gradient. These distribution characteristics seemed to be strongly influenced by the mixing process of freshwater and seawater, for both pH and total alkalinity had significant linear relationships with salinity and temperature. For pH, phytoplankton activities also had a significant impact upon its spatial distribution. During a period of 48 h, pH and total alkalinity changed within wide ranges for every layer of the two anchor stations, namely, Stas 13 and 20, which were located at the mixed water mass and seawater mass, respectively. For both Stas 13 and 20, pH and TA fluctuation of every layer could be very wide during a 4 h period. As a whole, the data of the two anchor stations showed that neither variations in salinity and temperature nor phytoplankton activities were the main factors strongly influencing the total alkalinity temporal variability on a small time scale. The data of Sta. 20 implied that both salinity variation and phytoplankton activities had a significant influence on pH temporal variability, but the same conclusion could not be drawn from the data of Sta. 13.

关键词： Changjiang Estuary pH total alkalinity spatial and temporal variations

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spatial and temporal variations of Daily Ranges of the Geomagnetic Vertical Component in the Chinese Mainland

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Earthquake Research in China 2013年第1期27卷 91-100页

作者： Li Junhui Li Qi Wang Xingzhou He Kang Tao Yuechao Chen Jun Earthquake Administration of Anhui Province National Geophysical Observatory at Mengcheng Institutes of Geophysics CEA

In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ranges. The results are summarized as follows: (1) temporally, we use regressive analysis and FFT analysis to analyze the data. The results show that the Z component daily ranges of all stations have an obvious cyclical variation, the computed Fourier spectra of all data sets have clearly resolved the required periodicities in the data, in the form of distinct peaks at days 365, 183, 22, and 73, and the power spectra of day 365 is the highest in all periods. (2) In terms of spatial variation, the daily ranges show nonlinear variation with latitude in China. The results show the existence of a point of inflexion (maximal value point) nearby at about 25°N, the daily ranges of Z rise from 15°~25°N and have a good linear decrease variation along with 25°~50°N. (3) Compared with the spatial and temporal variations of Z daily ranges with the Sq current inversion, we found that the spatial and temporal characteristics of Z ranges are decided mainly by the spatio-temporal evolution of the Sq current system. (4) If the latitudes of the maximum amplitudes of variation of the vertical component in the geomagnetic quiet days are roughly taken as the latitudes corresponding to the foci of Sq overhead current system, we can see that these latitudes of foci become higher in summer, are lowest in winter and highest during Equinoxes, displaying conspicuous monthly and daily variations. For two successive geomagnetic quiet days, the latitudes of foci may vary ten degrees.

关键词： Chinese mainland Geomagnetic Daily ranges of Z component spatial and temporal variations

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Spatiotemporal variations of ambient air pollutants and meteorological influences over typical urban agglomerations in China during the COVID-19 lockdown

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Journal of Environmental Sciences 2021年第8期33卷 26-38页

作者： Linping Fan Shuang Fu Xin Wang Qingyan Fu Haohao Jia Hao Xu Guimei Qin Xue Hu Jinping Cheng School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China China National Environmental Monitoring Center Beijing 100012China Shanghai Environmental Monitor Center Shanghai 200235China

To investigate the air quality change during the COVID-19 pandemic,we analyzed spatiotemporal variations of six criteria pollutants in nine typical urban agglomerations in China using ground-based data and examined meteorological influences through correlation analysis and backward trajectory analysis under different *** of PM2.5,PM10,NO2,SO2 and CO in urban agglomerations respectively decreased by 18%–45%(30%–62%),17%–53%(22%–39%),47%-64%(14%–41%),9%–34%(0%–53%)and 16%-52%(23%–56%)during Lockdown(Post-lockdown)period relative to Pre-lockdown ***2.5 pollution events occurred during Lockdown in Beijing-Tianjin-Hebe(BTH)and Middle and South Liaoning(MSL),and daily O3 concentration rose to gradeⅡstandard in Post-lockdown *** from the nationwide slump of NO2 during Lockdown period,a rebound(~40%)in Post-lockdown period was observed in Cheng-Yu(CY),Yangtze River Middle-Reach(YRMR),Yangtze River Delta(YRD)and Pearl River Delta(PRD).With slightly higher wind speed compared with 2019,the reduction of PM2.5(51%–62%)in Post-lockdown period is more than2019(15%–46%)in HC(Harbin-Changchun),MSL,BTH,CP(Central Plain)and SP(ShandongPeninsula),suggesting lockdown measures are effective to PM2.5 *** O3 concentrations generally increased during the lockdown,its increment rate declined compared with 2019 under similar sunlight duration and ***,unlike HC,MSL and BTH,which suffered from additional(>30%)air masses from surrounding areas after the lockdown,the polluted air masses reaching YRD and PRD mostly originated from the long-distance transport,highlighting the importance of joint regional governance.

关键词： COVID-19 Air pollutants spatial and temporal variations Urban agglomeration Meteorological condition China

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Spatiotemporal variations of aridity index over the Belt and Road region under the 1.5℃ and 2.0℃ warming scenarios

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Journal of Geographical Sciences 2020年第1期30卷 37-52页

作者： ZHOU Jian JIANG Tong WANG Yanjun Su Buda TAO Hui QIN Jiancheng ZHAI Jianqing Collaboration Innovation Center on Forecast and Evaluation of Meteorological Disasters/Institute for Disaster Risk Management/School of Geographical Science Nanjing University of Information Science&TechnologyNanjing 210044China National Climate Center China Meteorological AdministrationBeijing 100081China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyCASUrumqi 830011China University of Chinese Academy of Sciences Beijing 101408China

Aridity index reflects the exchanges of energy and water between the land surface and the atmosphere,and its variation can be used to forecast drought and flood patterns,which makes it of great significance for agricultural *** ratio of potential evapotranspiration and precipitation is applied to analyse the spatial and temporal distributions of the aridity index in the Belt and Road region under the 1.5℃and 2.0℃global warming scenarios on the basis of outputs from four downscaled global climate *** results show that:(1)Under the 1.5℃warming scenario,the area-averaged aridity index will be similar to that in 1986-2005(around 1.58),but the changes vary *** aridity index will increase by more than 5%in Central-Eastern Europe,north of West Asia,the monsoon region of East Asia and northwest of Southeast Asia,while it is projected to decrease obviously in the southeast of West *** the seasonal scale,spring and winter will be more arid in South Asia,and the monsoon region of East Asia will be slightly drier in summer compared with the reference ***,West Asia will be wetter in all seasons,except winter.(2)Relative to 1986-2005,both areal averaged annual potential evapotranspiration and precipitation are projected to increase,and the spatial variation of aridity index will become more obvious as well at the 2.0℃warming *** the aridity index over the entire region will be maintained at approximately 1.57 as that in 1.5℃,the index in Central-Eastern Europe,north of West Asia and Central Asia will grow rapidly at a rate of more than 20%,while that in West Siberia,northwest of China,the southern part of South Asia and West Asia will show a declining *** the seasonal scale,the increase of the aridity index in Central-Eastern Europe,Central Asia,West Asia,South Asia and the northern part of Siberia in winter will be obvious,and the monsoon region in East Asia will be drier in both summer and autumn.(3)Under the scena

关键词： 1.5℃and 2.0℃global warming scenarios aridity index spatial and temporal variations the Belt and Road region

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Spatio-temporal variations in ecological spaces and their ecological carrying status in China's mega-urban agglomerations

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Journal of Geographical Sciences 2022年第9期32卷 1683-1704页

作者： WANG Shihao HUANG Lin XU Xinliang LI Jiahui State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China

The rapid expansion of China’s urban agglomerations in recent decades has resulted in over-occupied ecological spaces and increased ecological pressure that are restricting healthy regional *** paper examines the structure and characteristics of distribution of“production-living-ecological”spaces in five mega-urban agglomerations in China:Beijing-Tianjin-Hebei(BTH),the Yangtze River Delta(YRD),Guangdong-Hong Kong-Macao Greater Bay Area(GBA),Chengdu-Chongqing(CY),and the middle reaches of the Yangtze River(MYR).We analyze spatial and temporal variations in the ecological spaces and factors influencing them from 1990 to 2020,and examine the comprehensive ecological carrying capacity and status of ecological spaces in the past 30 years based on the available water resources,regulation of water and air quality,and leisure and *** results show the following:(1)Urban agglomerations in different stages of formation and development represent varying area ratios of“ecological-production-living”*** modes of expansion and evolution of the living spaces are dominated by multi-center combinations as well as the spatial structure of ecological spaces,including barrier,compact,discrete,and fully enveloping spaces.(2)From 1990 to 2020,the area occupied by living spaces in urban agglomerations continued to increase significantly while that of spaces for ecological production *** in the GBA,ecological spaces have exhibited a trend of increase in area,especially in the past 10 *** area ratios and spatio-temporal variations in the“production-living-ecological”spaces indicate that the main functions of production and ecological spaces in mega-urban agglomerations have shifted from supply to regulation and culture,and reflect the transition from rapid urbanization to sustainable urbanization in China.(3)The comprehensive ecological carrying capacities of 78.6%,73.1%,54.5%,56.3%,and 25.8%of cities in BTH,YRD,GBA,CY and MYR are severely ove

关键词： mega-urban agglomerations “production-living-ecological”spaces ecological spaces ecological carrying capacity spatial and temporal variations

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Fine Particulate Pollution Characteristics in Jinan City

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 61-64页

作者： Zhang Guiqin Wang Zhaojun Liu Yutang Wilhelm Hoeflinger School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan Shandong 250101China Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China Jinan Environmental Protection Science Institute Jinan Shandong 250014China Vienna University of Technology Vienna 166A-1060Austria

The characteristics of fine particulate pollution(PM10 and PM2.5) were measured at urban and suburban sites in Jinan during the 2008-2009 heating and non-heating *** results showed that PM10 and PM2.5 pollution was quite serious,and PM mass concentration was higher during the heating season than the non-heating *** was the highest in the chemical factory and lowest in the development *** mass concentrations of PM10 and PM2.5 were linearly related,and the mass concentration ratio of PM2.5/PM10 was up to 0.59 in urban *** pollution in Jinan was related to local meteorological factors:PM2.5 mass concentration and humidity were positively correlated,and PM2.5 mass concentration was negatively correlated with both click on the temperature and wind speed,although wind speed varied more.

关键词： Fine Particles(PM2.5 and PM10) Pollution Characteristics spatial and temporal variations Meteorological factors.

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spatial distribution and temporal trends in potential evapotranspiration over Hengduan Mountains region from 1960 to 2009

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Journal of Geographical Sciences 2012年第1期22卷 71-85页

作者： ZHU Guofeng HE Yuanqing PU Tao WANG Xufeng JIA Wenxiong LI Zongxing XIN Huijuan State Key Laboratory of Cryosphere Sciences Yulong Snow Mountain Glaciers and Environmental Obser-vation Station Cold and Arid Regions Environmental and Engineering Research Institute CAS Graduate University of Chinese Academy of Sciences Research School of Arid Environment and Climate Change Lanzhou University College of Geography and Environment Science Northwest Normal University

Based on the meteorological data of 20 stations in the Hengduan Mountains region during 1961–2009, the annual and seasonal variation of potential evapotranspiration was analyzed in combination with the Penman-Monteith model. With the method of Spline interpolation under ArcGIS, the spatial distribution of potential evapotranspiration was presented to research the regional difference, and the correlation analysis was used to discuss the dominant factor affecting the potential evapotranspiration. The results indicated that the an-nual potential evapotranspiration showed a decreasing tendency since the 1960s, especially from the 1980s to 1990s, while it showed an increasing tendency since 2000. Regional potential evapotranspiration showed a rate of –0.17 mm a？1. Potential evapotranspiration in north, middle and south of the Hengduan Mountains exhibited decreasing trends over the studied period, and its regional trend was on the decline from southwest to northeast.

关键词： potential evapotranspiration Spline interpolation Penman-Monteith model spatial and temporal variations Hengduan Mountains

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