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Groundwater level monitoring-importance global groundwater monitoring network

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Journal of Groundwater Science and Engineering 2015年第4期3卷 295-305页

作者： Ramasamy Jayakumar Asia and Pacific Regional Bureau for Education UNESCO

The paper illustrates the concept, methodology, essential components and importance of groundwater level monitoring in terms of various aquifers such as multiple aquifer, karst aquifer and other aquifers. The groundwater resources in Mekong countries including Cambodia, Laos PDR, Myanmar, Thailand and Vietnam have also been reviewed. Finally, the author briefly presents Global Groundwater monitoring network.

关键词： Groundwater monitoring Groundwater resources Mekong countries monitoring network

The Impact of the Numbers of monitoring Stations on the National and Regional Air Quality Assessment in China During 2013-18

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Advances in Atmospheric Sciences 2022年第10期39卷 1709-1720页

作者： Hongyan LUO Xiao TANG Huangjian WU Lei KONG Qian WU Kai CAO Yating SONG Xuechun LUO Yao WANG Jiang ZHU Zifa WANG LAPC&ICCES Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

China national air quality monitoring network has become the core data source for air quality assessment and management in China.However,during network construction,the significant change in numbers of monitoring sites with time is easily ignored,which brings uncertainty to air quality assessments.This study aims to analyze the impact of change in numbers of stations on national and regional air quality assessments in China during 2013-18.The results indicate that the change in numbers of stations has different impacts on fine particulate matter(PM_(2.5))and ozone concentration assessments.The increasing number of sites makes the estimated national and regional PM_(2.5) concentration slightly lower by 0.6−2.2μg m^(−3) and 1.4−6.0μg m^(−3) respectively from 2013 to 2018.The main reason is that over time,the monitoring network expands from the urban centers to the suburban areas with low population densities and pollutant emissions.For ozone,the increasing number of stations affects the long-term trends of the estimated concentration,especially the national trends,which changed from a slight upward trend to a downward trend in 2014−15.Besides,the impact of the increasing number of sites on ozone assessment exhibits a seasonal difference at the 0.05 significance level in that the added sites make the estimated concentration higher in winter and lower in summer.These results suggest that the change in numbers of monitoring sites is an important uncertainty factor in national and regional air quality assessments,that needs to be considered in long-term concentration assessment,trend analysis,and trend driving force analysis.

关键词： monitoring network newly added sites PM_(2.5) ozone

Spatiotemporal trends of PM_(2.5) and its major chemical components at urban sites in Canada

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Journal of Environmental Sciences 2021年第5期33卷 1-11页

作者： Huanbo Wang Leiming Zhang Irene Cheng Xiaohong Yao Ewa Dabek-Zlotorzynska School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Air Quality Research Division Science and Technology BranchEnvironment and Climate Change CanadaTorontoCanada Lab of Marine Environmental Science and Ecology Ministry of EducationOcean University of ChinaQingdao 266100China Air Quality Research Division Science and Technology BranchEnvironment and Climate Change CanadaOttawaCanada

To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM_(2.5) data have been collected across Canada through the National Air Pollution Surveillance network in the past decade. 24-hr time integrated PM_(2.5) collected at seven urban and two rural sites during 2010-2016 were analyzed to characterize geographical and seasonal patterns and associated potential causes. Site-specific seven-year mean gravimetric PM_(2.5) mass concentrations ranged from 5.7 to 9.6 μg/m^(3). Seven-year mean concentrations of SO_(4)^(2-), NO_(3)^(-), NH_(4)^(+), organic carbon(OC), and elemental carbon(EC) were in the range of 0.68 to 1.6, 0.21 to 1.5, 0.27 to 0.71, 1.1 to 1.9, and 0.37 to 0.71 μg/m^(3), accounting for 10.8%-18.1%, 3.7%-16.7%, 4.7%-7.4%, 18.4%-21.0%, and 6.4%-10.6%, respectively, of gravimetric PM_(2.5) mass. PM_(2.5) and its five major chemical components showed higher concentrations in southeastern Canada and lower values in Atlantic Canada, with the seven-year mean ratios between the two regions being on the order of 1.7 for PM_(2.5) and 1.8-7.1 for its chemical components. When comparing the concentrations between urban and rural sites within the same region, those of SO_(4)^(2-) and NH_(4)^(+) were comparable, while those of NO_(3)^(-), OC, and EC were around 20%, 40%-50%, and 70%-80%, respectively, higher at urban than rural sites, indicating the regional scale impacts of SO_(4)^(2-) and NH_(4)^(+) and effects of local sources on OC and EC. Monthly variations generally showed summertime peaks for SO_(4)^(2-) and wintertime peaks for NO_(3)^(-), but those of NH_(4)^(+), OC, and EC exhibited different seasonality at different locations.

关键词： Fine particulate matter Aerosol chemical composition monitoring network

ORPOM model for optimum distribution of tree ring sampling based on the climate observation network

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Research in Cold and Arid Regions 2010年第6期2卷 547-554页

作者： Long Ma TingXi Liu YanYun Luo HongLan Ji ShiQiang Li JunXiao Shi Water Conservancy and Civil Engineering College of Inner Mongolia Agricultural University Hohhot Inner Mongolia O10018 China

Tree ring dating plays an important role in obtaining past climate information. The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential. The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation network (ORPOM model) is presented in this article. In this setup, the tree rings in a typical region are used for surface representation, by applying excellent correlation with the climate information as the main principle. Taking the Horqin Sandy Land in the cold and arid region of China as an example, the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model, which is considered a reasonably practical scheme.3

关键词： climate monitoring network tree ring sampling site optimum model Horqin Sandy Land

对我国青少年体质健康监测服务体系的调查研究

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