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Chemical and Isotopic Characters of the Water and Suspended Particulate Materials in the Yellow River and Their Geological and environmental implications

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 285-351页

作者： DING Tiping GAO Jianfei TIAN Shihong WANG Huaibai LI Ming WANG Chengyu LUO Xurong HANG Dan MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China MLR Key Laboratory of Isotope Geology CAGSBeijing 100037China Hydrological Bureau YRCCZhengzhou 450004China

The chemical and isotopic characteristics of the water and suspended particulate materials （SPM） in the Yellow River were investigated on the samples collected from 29 hydrological monitoring stations in the mainstem and several major tributaries during 2004 to 2007. The JD and δ^18O values of the Yellow River water vary in large ranges from -32%0 to -91‰ and from -3.1‰ to -12.5‰, respectively. The characters of H and O isotope variations indicate that the major sources of the Yellow River water are meteoric water and snow melting water, and water cycle in the Yellow River basin is affected strongly by evaporation process and human activity. The average SPM content （9.635 g/L） of the Yellow River is the highest among the world large rivers. Compared with the Yangtze River, the Yellow River SPM has much lower clay content and significantly higher contents of clastic silicates and carbonates. In comparison to the upper crust rocks, the Yellow River SPM contains less SiO2, CaO, K2O and Na2O, but more TFe203, Co, Ni, Cu, Zn, Pb and Cd. The abnormal high Cd contents found in some sample may be related to local industrial activity. The REE contents and distribution pattern of the Yellow River SPM are very close to the average value of the global shale. The average δ^30Sisp in the Yellow River （-0.11‰） is slightly higher than the average value （-0.22‰） of the Yangtze River SPM. The major factors controlling the δ^30Si SPM of the Yellow River are the soil supply, the isotopic composition of the soil and the climate conditions. The TDS in the Yellow River are the highest among those of world large rivers. Fair correlations are observed among Cl, Na^＋, K^＋, and Mg^2＋ contents of the Yellow River water, indicating the effect of evaporation. The Ca^2＋ and Sr^2＋ concentrations show good correlation to the SO42 concentration rather than HCO3-concentration, reflecting its origin from evaporates. The NO3-contents are affected by farmland fertilization. The Cu, Zn and Cd contents in

关键词： Yellow River stable isotopes water chemistry suspended particulate materials (SPM) hydrology environmental implication

Morphological Characteristics and environmental implications of Phytoliths in Topsoils from Different Vegetation Zones on Northern Slope of Changbai Mountains,China

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Chinese Geographical Science 2010年第6期20卷 506-512页

作者： QIAO Zhihe JIE Dongmei LIU Hongmei GE Yong ZHANG Hongyan College of Urban and environmental Science Northeast Normal UniversityChangchun 130024China Daqing Normal University Daqing 163001China

The Changbai Mountains,located in the temperate monsoon climate zone of East Asia,is an ideal loca-tion for the research on timberline response to global *** this study,the topsoils were collected from different vertical vegetation zones on the northern slope of the Changbai Mountains,Northeast China in August 2009,and phytoliths in the soil samples were extracted by using wet oxidation method and identified with Motic 2.0 microscope in *** results show that phytoliths are abundant in the topsoils of the study *** herbal phytoliths are primarily composed of elongated,tooth-shaped,point-shaped and hat-shaped phytoliths,as well as a small amount of fan-shaped and square-shaped *** elongated,tooth-shaped,point-shaped and hat-shaped phytoliths are representative of cold climate,while fan-shaped and square-shaped ones are representative of warm and humid *** the conifer broadleaved mixed forest zone,coniferous forest zone and broadleaf forest zone,there are close correlations between vegetation and woody phytoliths in the topsoils,indicating that the woody plants of a region can be reconstructed from the woody phytolith assemblages in the ***,the topsoil phytolith assemblages can also be used to reconstruct the understory herbs *** phytolith assemblages in the topsoils of the forest community and herbal community differ significantly,which can help indicate the historical location of the timberline.

关键词： topsoil phytolith timberline environmental implication vertical vegetation zones Changbai Mountains

Chemical and Isotopic Characteristics of the Water and Suspended Particulate Materials in the Yangtze River and Their Geological and environmental implications

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 276-360页

作者： DING Tiping GAO Jianfei TIAN Shihong SHI Guoyu CHEN Feng WANG Chengyu LUO Xurong HAN Dan MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources CAGS Open Research Laboratory of Isotope Geology Hydrological Bureau CWRC

The chemical and isotopic characteristics of the water and suspended particulate materials（SPM） in the Yangtze River were investigated on the samples collected from 25 hydrological monitoring stations in the mainsteam and 13 hydrological monitoring stations in the major tributaries during 2003 to 2007. The water samples show a large variation in both δD（ 30‰ to 112‰） and δ18O（ 3.8‰ to 15.4‰） values. Both δD and δ18O values show a decrease from the river head to the Jinsha Jiang section and then increase downstream to the river mouth. It is found that the oxygen and hydrogen isotopic compositions of the Yangtze water are controlled by meteoric precipitation, evaporation, ice（and snow） melting and dam building. The Yangtze SPM concentrations show a large variation and are well corresponded to the spatial and temporal changes of flow speed, runoff and SPM supply, which are affected by the slope of the river bed, local precipitation rate, weathering intensity, erosion condition and anthropogenic activity. The Yangtze SPM consists of clay minerals, clastic silicate and carbonate minerals, heavy minerals, iron hydroxide and organic compounds. From the upper to lower reaches, the clay and clastic silicate components in SPM increase gradually, but the carbonate components decrease gradually, which may reflect changes of climate and weathering intensity in the drainage area. Compared to those of the upper crust rocks, the Yangtze SPM has lower contents of SiO2, CaO, K2 O and Na2 O and higher contents of TFe2 O3 and trace metals of Co, Ni, Cu, Zn, Pb and Cd. The ΣREE in the Yangtze SPM is also slightly higher than that of the upper crust. From the upper to lower reaches, the CaO and MgO contents in SPM decrease gradually, but the SiO2 content increases gradually, corresponding to the increase of clay minerals and decrease of the carbonates. The δ30SiSPM values（ 1.1‰ to 0.3‰） of the Yangtze SPM are similar to those of the average shale, but lower than those of the granite rock

关键词： Yangtze River stable isotopes water chemistry Suspended Particulate Materials(SPM) hydrology environmental implication

Environment implications of China's WTO Accession

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Chinese Journal of Population,Resources and Environment 2006年第1期4卷 3-14页

作者： Li Shantong He Jianwu Department Research Centre The State CouncilBeijing 100010China

China's WTO accession will have important environmental implications. This article aims at providing environmental analysis of the impact of China's accession to the WTO, based on its final offer for WTO accession and a 53-sector, recursive dynamic computable general equilibrium (CGE) model of China. We try to provide some empirical evidences for policy makers to evaluate the effects of China's WTO accession from environmental prospective.

关键词： WTO CGE model environmental implication

Multifaceted Insight into Sensitivity Analysis and environmental Impact on Human Health of Soil Contamination Risk Assessment

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Environment & Health 2023年第3期1卷 214-227页

作者： Hao Zhang Ping Du Bei Yuan Yunhui Zhang Juan Chen Hupeng Liu Aiyang Li Yuquan Wei Yanna Xiong Bin Zhao Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Chinese Research Academy of environmental Sciences Beijing 100012China Beijing Key Laboratory of Biodiversity and Organic Farming College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Institute of Eco-environmental and Soil Sciences Guangdong Academy of SciencesGuangzhou 510650China Department of environmental Sciences Norwegian University of Life SciencesÅs N-1432Norway School of Environment Tsinghua UniversityBeijing 100084China

Sensitivity analysis is a valuable method for evaluating the impact of model parameters on health risk characterization,thereby supporting the prediction of critical uncertainty ***,limitations arise in terms of cross-disciplinary discussions and in-depth analyses of previous *** overcome these limitations,a systematic and multifaceted approach was introduced for analyzing the parameter sensitivities in soil contamination risk *** approach specifically targeted the 12 main parameters associated with 65 soil contaminants for health risk assessment,employing detailed authoritative statistics for risk *** analysis revealed that identified heavy metals and organics were influenced by key parameters,such as PM_(10),body weight of adults(BW_(a)),daily air inhalation rate of adults(DAIR_(a)),air exchange rate(ER),and typical soil ***_(10) showed a positive 100%correlation with inorganics and metals,but BW_(a) and DAIR_(a) exhibited different impacts on different chemicals,with an increase in potential risk observed with higher BW_(a) and lower DAIR_(a).Furthermore,incorporating soil parameters in the analysis showed that compact soil could improve the protection against vapor organic compounds for human *** refined study presents a comprehensive strategy for sensitivity analysis in health risk assessment of soil contamination,thereby offering substantial support for the protection and preservation of human health.A logical framework also was provided for addressing the limitations of sensitivity analysis and facilitating an understanding of the complex relationships between model parameters and the health risk of soil contamination.

关键词： Soil contamination health risk assessment sensitivity analysis exposure parameter environmental implication

Current and Future Research Trends of environmental Nanomaterials

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Current and Future Research Trends of Environmental Nanomate...