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Summer Atmospheric Water Cycle under the Transition Influence of the Westerly and Summer Monsoon over the Yarlung Zangbo River Basin in the Southern Tibetan Plateau
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作者 Qianhui MA Chunyan ZHANG +1 位作者 Donghai WANG Zihao PANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期830-846,共17页
This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The ... This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The evolutions of moisture properties under the influence of the westerly and summer southerly monsoon are examined using 5-yr multi-source measurements and ERA5 reanalysis data.Note that moisture consumption in this study is associated with clouds,precipitation,and diabatic heating.Compared to the midstream and downstream regions,the upstream region has less moisture,clouds,and precipitation,where the moisture is brought by the westerly.In early August,the vertical wet advection over this region becomes enhanced and generates more high clouds and precipitation.The midstream region has moisture carried by the westerly in June and by the southerly monsoon from July to August.The higher vertical wet advection maximum here forms more high clouds,with a precipitation peak in early July.The downstream region is mainly affected by the southerly-driven wet advection.The rich moisture and strong vertical wet advection here produce the most clouds and precipitation among the three regions,with a precipitation peak in late June.The height of the maximum moisture condensation is different between the midstream region(325 hPa)and the other two regions(375 hPa),due to the higher upward motion maximum in the midstream region.The diabatic heating structures show that stratiform clouds dominate the upstream region,stratiform clouds and deep convection co-exist in the midstream region,and deep convection systems characterize the downstream region. 展开更多
关键词 Yarlung Zangbo River Basin atmospheric water cycle constrained variational analysis moisture source and consumption
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Stable Isotopic Signatures of NO3 in Waste Water Effluent and Los Angeles River
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作者 Isaac Hall Mohammad Hassan Rezaie Boroon 《Journal of Water Resource and Protection》 CAS 2024年第1期102-122,共21页
A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary... A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health. 展开更多
关键词 Metropolitan City Los Angeles Treatment Plants Sewage Treatment Nitrate source Isotope Signatures water Quality
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Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River
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作者 ZHANG Han BURNETT CWilliam +5 位作者 ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao 《Journal of Ocean University of China》 CAS CSCD 2024年第1期99-108,共10页
Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and ... Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(<32µm)was mainly from the erosion of soil along the lower reaches of the Yellow River,while coarse SPM(>32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea. 展开更多
关键词 the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator
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Disinfection Byproducts and Their Precursors in Drinking Water Sources:Origins,Influencing Factors,and Environmental Insights
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作者 Rong Xiao Yang Deng +1 位作者 Zuxin Xu Wenhai Chu 《Engineering》 SCIE EI CAS CSCD 2024年第5期36-50,共15页
Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as ... Tracing the contamination origins in water sources and identifying the impacts of natural and human processes are essential for ecological safety and public health.However,current analysis approaches are not ideal,as they tend to be laborious,time-consuming,or technically difficult.Disinfection byproducts(DBPs)are a family of well-known secondary pollutants formed by the reactions of chemical disinfectants with DBP precursors during water disinfection treatment.Since DBP precursors have various origins(e.g.,natural,domestic,industrial,and agricultural sources),and since the formation of DBPs from different precursors in the presence of specific disinfectants is distinctive,we argue that DBPs and DBP precursors can serve as alternative indicators to assess the contamination in water sources and identify pollution origins.After providing a retrospective of the origins of DBPs and DBP precursors,as well as the specific formation patterns of DBPs from different precursors,this article presents an overview of the impacts of various natural and anthropogenic factors on DBPs and DBP precursors in drinking water sources.In practice,the DBPs(i.e.,their concentration and speciation)originally present in source water and the DBP precursors determined using DBP formation potential tests—in which water samples are dosed with a stoichiometric excess of specific disinfectants in order to maximize DBP formation under certain reaction conditions—can be considered as alternative metrics.When jointly used with other water quality parameters(e.g.,dissolved organic carbon,dissolved organic nitrogen,fluorescence,and molecular weight distribution)and specific contaminants of emerging concern(e.g.,certain pharmaceuticals and personal care products),DBPs and DBP precursors in drinking water sources can provide a more comprehensive picture of water pollution for better managing water resources and ensuring human health. 展开更多
关键词 Disinfection byproducts Disinfection byproduct precursors Drinking water sources Contamination indicator Natural factors Human factors
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Riparian habitat quality as an indicator of land use/land cover effects on riverine water quality
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作者 Shijie Gu Siyue Li 《Geography and Sustainability》 CSCD 2024年第1期135-143,共9页
Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality ... Riparian land use/land cover(LULC)plays a crucial role in maintaining riverine water quality by altering the transport of pollutants and nutrients.Nevertheless,establishing a direct relationship between water quality and LULC is challenging due to the multi-indicator nature of both factors.Water quality encompasses a multitude of physical,chemical,and biological parameters,while LULC represents a diverse array of land use types.Riparian habitat quality(RHQ)serves as an indicator of LULC.Yet,it remains to be seen whether RHQ can act as a proxy of LULC for assessing the impact of LULC on riverine water quality.This study examines the interplay between RHQ,LULC and water quality,and develops a comprehensive indicator to predict water quality.We measured several water quality parameters,including pH(potential of hydrogen),TN(total nitrogen),TP(total phosphorus),T_(water)(water temperature),DO(dissolved oxygen),and EC(electrical conductivity)of the Yue and Jinshui Rivers draining to the Han River during 2016,2017 and 2018.The water quality index(WQI)was further calculated.RHQ is assessed by the InVEST(Integrated Valuation of Ecosystem Services and Tradeoffs)model.Our study found noticeable seasonal differences in water quality,with a higher WQI observed in the dry season.The RHQ was strongly correlated with LULC compositions.RHQ positively correlated with WQI,and DO concentration and vegetation land were negatively correlated with T_(water),TN,TP,EC,cropland,and construction land.These correlations were stronger in the rainy season.Human-dominated land,such as construction land and cropland,significantly contributed to water quality degradation,whereas vegetation promoted water quality.Regression models showed that the RHQ explained variations in WQI better than LULC types.Our study concludes that RHQ is a new and comprehensive indicator for predicting the dynamics of riverine water quality. 展开更多
关键词 water quality index Land use/land cover Riparian habitat quality Drinking water source areas
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Evaluation of Air-Kerma and Absorbed Dose to Water for External Radiotherapy Beam Using Ionization Chamber
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作者 Collins Omondi Margaret Chege Samson Omondi 《Open Journal of Radiology》 2024年第3期113-124,共12页
Radiotherapy is the most widely applied oncologic treatment modality utilizing ionizing radiation. A high degree of accuracy, reliability and reproducibility is required for a successful treatment outcome. Measurement... Radiotherapy is the most widely applied oncologic treatment modality utilizing ionizing radiation. A high degree of accuracy, reliability and reproducibility is required for a successful treatment outcome. Measurement using ionization chamber is a prerequisite for absorbed dose determination for external beam radiotherapy. Calibration coefficient is expressed in terms of air kerma and absorbed dose to water traceable to Secondary Standards Dosimetry Laboratory. The objective of this work was to evaluate the level of accuracy of ionization chamber used for clinical radiotherapy beam determination. Measurement and accuracy determination were carried out according to IAEA TRS 398 protocol. Clinical farmers type ionization chamber measurement and National Reference standard from Secondary Standards Dosimetry Laboratory were both exposed to cobalt-60 beam and measurement results compared under the same environmental conditions. The accuracy level between National Reference Standard and clinical radiotherapy standard was found to be −1.92% and −2.02% for air kerma and absorbed dose to water respectively. To minimize the effect of error and maximize therapeutic dose during treatment in order to achieve required clinical outcome, calibration factor was determined for air kerma (Nk) as 49.7 mGy/nC and absorbed dose to water ND, as 52.9 mGy/nC. The study established that radiotherapy beam measurement chain is prone to errors. Hence there is a need to independently verify the accuracy of radiation dose to ensure precision of dose delivery. The errors must be accounted for during clinical planning by factoring in calibration factor to minimize the systematic errors during treatment, and thereby providing enough room to achieve ±5% dose delivery to tumor target as recommended by ICRU. 展开更多
关键词 Absorbed Dose to water Air Kerma Co-60 source Calibration SSDL Radiotherapy Beam METROLOGY Accuracy and Accuracy
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Source apportionment of river water pollution in a typical agricultural city of Anhui Province, eastern China using multivariate statistical techniques with APCS– MLR 被引量:2
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作者 Kai Chen Qi-meng Liu +2 位作者 Wei-hua Peng Yu Liu Zi-tao Wang 《Water Science and Engineering》 EI CAS CSCD 2023年第2期165-174,共10页
The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential po... The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential pollution sources. In this study, 99 water samples were collected from a river in a typical agricultural city of Anhui Province in eastern China, and these samples were analyzed in terms of pH, electrical conductivity, and the concentrations of F-, Cl-, SO42-, Na+, K+, Mg2+, Ca2+, As, Cr, Cu, Zn, and Pb. Cluster analysis, co-occurrence network analysis, and principal component analysis/factor analysis were conducted to qualitatively identify the potential sources of river water pollution in the study area. An absolute principal component score-multiple linear regression receptor model was used to quantitatively evaluate the contribution of each source to water quality parameters. The results showed that all observed water quality indices met the quality criteria specified in the Chinese drinking water standards, except for pH, ρ(F-), ρ(SO42-), and ρ(As). The heat map showed that the frequent recharge of pollutants from the tributaries during the wet season was the main reason for the deterioration of water quality. Five sources of river water pollution were identified, and their contribution ratios in a descending order were as follows: the geogenic process (24%) > agricultural activities (21%) > poultry farming sources (17%) > domestic pollution (9%) > transportation pollution (5%). Therefore, controlling pollution from agricultural activities, strengthening the regulation of livestock farming, and improving the sewage network are the recommended strategies for improving the quality of surface water resources in this area. 展开更多
关键词 Surface water water quality source apportionment APCS-MLR model Huaihe river basin
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Dataset of Comparative Observations for Land Surface Processes over the Semi-Arid Alpine Grassland against Alpine Lakes in the Source Region of the Yellow River 被引量:2
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作者 Xianhong MENG Shihua LYU +13 位作者 Zhaoguo LI Yinhuan AO Lijuan WEN Lunyu SHANG Shaoying WANG Mingshan DENG Shaobo ZHANG Lin ZHAO Hao CHEN Di MA Suosuo LI Lele SHU Yingying AN Hanlin NIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期1142-1157,共16页
Thousands of lakes on the Tibetan Plateau(TP) play a critical role in the regional water cycle, weather, and climate. In recent years, the areas of TP lakes underwent drastic changes and have become a research hotspot... Thousands of lakes on the Tibetan Plateau(TP) play a critical role in the regional water cycle, weather, and climate. In recent years, the areas of TP lakes underwent drastic changes and have become a research hotspot. However, the characteristics of the lake-atmosphere interaction over the high-altitude lakes are still unclear, which inhibits model development and the accurate simulation of lake climate effects. The source region of the Yellow River(SRYR) has the largest outflow lake and freshwater lake on the TP and is one of the most densely distributed lakes on the TP. Since 2011,three observation sites have been set up in the Ngoring Lake basin in the SRYR to monitor the lake-atmosphere interaction and the differences among water-heat exchanges over the land and lake surfaces. This study presents an eight-year(2012–19), half-hourly, observation-based dataset related to lake–atmosphere interactions composed of three sites. The three sites represent the lake surface, the lakeside, and the land. The observations contain the basic meteorological elements,surface radiation, eddy covariance system, soil temperature, and moisture(for land). Information related to the sites and instruments, the continuity and completeness of data, and the differences among the observational results at different sites are described in this study. These data have been used in the previous study to reveal a few energy and water exchange characteristics of TP lakes and to validate and improve the lake and land surface model. The dataset is available at National Cryosphere Desert Data Center and Science Data Bank. 展开更多
关键词 field observation dataset lake-atmosphere interaction energy and water exchanges the source region of the Yellow River Tibetan Plateau
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Mechanism of nitrogen loss driven by soil and water erosion in water source areas
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作者 Rongjia Wang Jianfeng Zhang +1 位作者 Chunju Cai Shufeng Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1985-1995,共11页
Nitrogen(N)present in drinking water as dissolved nitrates can directly affect people’s health,making it important to control N pollution in water source areas.N pollution caused by agricultural fertilizers can be co... Nitrogen(N)present in drinking water as dissolved nitrates can directly affect people’s health,making it important to control N pollution in water source areas.N pollution caused by agricultural fertilizers can be controlled by reducing the amount of fertilizer applied,but pollution caused by soil and water erosion in hilly areas can only be controlled by conservation forests.The catchment area around Fushi Reservoir was selected as a test site and mechanisms of N loss from a vertical spatial perspective through field observations were determined.The main N losses occurred from June to September,accounting for 85.9-95.9%of the annual loss,with the losses in June and July accounting for 46.0%of the total,and in August and September for 41.9%.The N leakage from the water source area was effectively reduced by 38.2%through the optimization of the stand structure of the conservation forests.Establishing well-structured forests for water conservation is crucial to ensure the security of drinking water.This preliminary research lays the foundation for revealing then loss mechanisms in water source areas and improving the control of non-point source pollution in these areas. 展开更多
关键词 water source areas Nitrogen loss Non-point source pollution water quality Surface runoff
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Source analysis of dissolved heavy metals in the Shaying River Basin,China
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作者 Ya-wei Zhang Yun-tao Liu +6 位作者 Zi-wen Wang Yu Cao Xiao-ran Tu Di Cao Shuai Yuan Xiao-man Cheng Lian-sheng Zhang 《Journal of Groundwater Science and Engineering》 2023年第4期408-421,共14页
Over the years,the Shaying River Basin has experienced frequent instances of river pollution.The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying... Over the years,the Shaying River Basin has experienced frequent instances of river pollution.The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying River has transformed it a major tributary with relatively serious pollution challenge within the upper reaches of Huaihe River Basin.To study the sources of manganese(Mn),chromium(Cr),nickel(Ni),arsenic(As),cadmium(Cd)and lead(Pb)in Shaying River water,123 sets of surface water samples were collected from 41 sampling points across the entire basin during three distinct phases from 2019 to 2020,encompassing normal water period,dry season and wet season.The primary origins of heavy metals in river water were determined by analyzing the heavy metal contents in urban sewage wastewater,industrial sewage wastewater,groundwater,mine water,and the heavy metal contributions from agricultural non-point source pollution.The analytical findings reveal that Mn primarily originates from shallow groundwater used for agricultural irrigation,While Cr mainly is primarily sourced from urban sewage treatment plant effluents,coal washing wastewater,tannery wastewater,and industrial discharge related to metal processing and manufacturing.Ni is mainly contributed by urban sewage treatment plant effluents and industrial wastewater streams associated with machinery manufacturing and metal processing.Cd primarily linked to industrial wastewater,particularly from machinery manufacturing and metal processing facilities,while Pb is predominantly associated with urban sewage treatment plant effluents and wastewater generated in Pb processing and recycling wastewater.These research provides a crucial foundation for addressing the prevention and control of dissolved heavy metals at their sources in the Shaying River. 展开更多
关键词 Industrial waste Urban sewage Mine water Agricultural non-point source pollution
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Identification of Mine Water Inrush Source Based on PCA-BP Neural Network
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作者 Mingcheng Ning Haifeng Lu 《International Journal of Geosciences》 2023年第8期710-718,共9页
It is of great significance to analyze the chemical indexes of mine water and develop a rapid identification system of water source, which can quickly and accurately distinguish the causes of water inrush and identify... It is of great significance to analyze the chemical indexes of mine water and develop a rapid identification system of water source, which can quickly and accurately distinguish the causes of water inrush and identify the source of water inrush, so as to reduce casualties and economic losses and prevent and control water inrush disasters. Taking Ca<sup>2+</sup>, Mg<sup>2+</sup>, Na<sup>+</sup> + K<sup>+</sup>, , , Cl<sup>-</sup>, pH value and TDS as discriminant indexes, the principal component analysis method was used to reduce the dimension of data, and the identification model of mine water inrush source based on PCA-BP neural network was established. 96 sets of data of different aquifers in Panxie mining area were selected for prediction analysis, and 20 sets of randomly selected data were tested, with an accuracy rate of 95%. The model can effectively reduce data redundancy, has a high recognition rate, and can accurately and quickly identify the water source of mine water inrush. 展开更多
关键词 Mine water Inrush Analysis of Hydrochemical Characteristics Principal Component Analysis (PCA) Back Propagation Neural Networks water source Identification
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Estimation of water balance in the source region of the Yellow River based on GRACE satellite data 被引量:8
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作者 Min XU BaiSheng YE +2 位作者 QiuDong ZHAO ShiQing ZHANG Jiang WANG 《Journal of Arid Land》 SCIE CSCD 2013年第3期384-395,共12页
Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents... Water storage has important significance for understanding water cycles of global and local domains and for monitoring climate and environmental changes. As a key variable in hydrology, water storage change represents the sum of precipitation, evaporation, surface runoff, soil water and groundwater exchanges. Water storage change data during the period of 2003-2008 for the source region of the Yellow River were collected from Gravity Recovery and Climate Experiment (GRACE) satellite data. The monthly actual evaporation was estimated according to the water balance equation. The simulated actual evaporation was significantly consistent and correlative with not only the observed pan (20 cm) data, but also the simulated results of the version 2 of Simple Biosphere model. The average annual evaporation of the Tangnaihai Basin was 506.4 mm, where evaporation in spring, summer, autumn and winter was 130.9 mm, 275.2 mm, 74.3 mm and 26.1 mm, and accounted for 25.8%, 54.3%, 14.7% and 5.2% of the average annual evaporation, respectively, The precipitation increased slightly and the actual evaporation showed an obvious decrease. The water storage change of the source region of the Yellow River displayed an increase of 0.51 mm per month from 2003 to 2008, which indicated that the storage capacity has significantly increased, probably caused by the degradation of permafrost and the increase of the thickness of active layers. The decline of actual evaporation and the increase of water storage capacity resulted in the increase of river runoff. 展开更多
关键词 actual evaporation GRACE satellite data water storage change water balance equation source region of the Yellow River
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Genotoxicity evaluation and a primary risk assessment of organic pollutants in the drinking water sources of Nanjing, China 被引量:6
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作者 LI Yi-qiang WU Yu-lin +1 位作者 CHEN Yuan-gao KONG Zhi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期983-988,共6页
An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In t... An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In this study, the comet assay was conducted to investigate the genotoxicity to human body caused by organic concentrates in the drinking water sources of Nanjing City from Yangtze River of China, and health and ecology risk due to expose to these organic pollutants were evaluated with the multimedia environmental assessment system (MEAS). For all the water samples, they were collected from four different locations in the drinking water sourcr samples, es of Nanjing City. The results of the comet assay showed that all the organic concentrates from the water samples could induce different levels DNA damages on human peripheral blood lymphocytes, and a statistically significant difference (p〈0.01) was observed compared with the solvent control, which demonstrated the genotoxicity was in existence. According to the ambient severity (AS) of individual compound, we had sorted out the main organic pollutants in the drinking water source of the four waterworks, and the results showed that there was some potential hazard to human body for all the source water, namely the total ambient severity (TAS) of health for each water source was more than 1. However, the TAS of ecology for each water source was less than 1, which indicated that it was safe to ecology. The results of this investigation demonstrate the application of the comet assay and the MEAS in aquatic environmental monitoring studies, and the comet assay found to be fast, sensitive, and suitable for genotoxicity monitoring programs of drinking water source. 展开更多
关键词 GENOTOXICITY comet assay risk assessment organic pollutants drinking water sources Nanjing City
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Assessment of Point and Nonpoint Sources Pollution in Songhua River Basin,Northeast China by Using Revised Water Quality Model 被引量:14
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作者 YANG Yuhong YAN Baixing SHEN Wanbin 《Chinese Geographical Science》 SCIE CSCD 2010年第1期30-36,共7页
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify th... Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source.In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps(S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin.Chemical oxygen demand(COD) and ammonia nitrogen(NH 3-N) loads were estimated.Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively.NH 3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively.Point source pollution was stronger than nonpoint source pollution in the study area at present.The water quality of upstream was better than that of downstream of the rivers and cities.It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin.The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating. 展开更多
关键词 ammonia nitrogen chemical oxygen demand nonpoint source pollution point source pollution revised water quality model Songhua River Basin
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Connotation and principles of ecological compensation in water source reserve areas based on the theory of externality 被引量:4
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作者 Aimin Wang Yanxiang Ge Xiangyan Geng 《Chinese Journal of Population,Resources and Environment》 2016年第3期189-196,共8页
Understanding the connotation and principles of ecological compensation in water source reserve areas is the basis and guarantee for establishing and improving the ecological compensation mechanism of water source res... Understanding the connotation and principles of ecological compensation in water source reserve areas is the basis and guarantee for establishing and improving the ecological compensation mechanism of water source reserve areas.First,this paper reviews the three stages of ecological compensation research progress.Based on the review,using the theory of externality,the ecological environment system of water source reserve areas is then analyzed.This paper argues that the connotation of ecological compensation in water source reserve areas is a kind of institutional arrangement,which is designed to internalize externalities.Finally,based on the understanding of the connotation of ecological compensation in water source reserve areas,five principles for establishing and improving the ecological compensation mechanism are proposed,including the principle of fairness and justice,the principle of equivalence of equality and responsibility,the principle of flexibility and effectiveness,the principle of "earmark funds,and implementation by law," and the principle of government compensation supplemented with market compensation. 展开更多
关键词 water source reserve areas ecological compensation EXTERNALITY CONNOTATION PRINCIPLE
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An attribute recognition model based on entropy weight for evaluating the quality of groundwater sources 被引量:21
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作者 CHEN Suo-zhong WANG Xiao-jing ZHAO Xiu-jun 《Journal of China University of Mining and Technology》 EI 2008年第1期72-75,共4页
In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by ... In our study, entropy weight coefficients, based on Shannon entropy, were determined for an attribute recognition model to model the quality of groundwater sources. The model follows the theory previously proposed by Chen Q S. In the model, firstly, the author establishes the attribute space matrix and determines the weight based on Shannon entropy theory; secondly, calculates attribute measure; thirdly, evaluates that with confidence criterion and score criterion; finally, an application example is given. The results show that the water quality of the groundwater sources for the city comes up to the grade II or III standard. There is no pollution that obviously exceeds the standard and the water can meet people’s needs .The results from an evaluation of this model are in basic agreement with the observed situation and with a set pair analysis (SPA) model. 展开更多
关键词 water quality evaluation groundwater sources entropy weigh attribute recognition model
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New perspective of Miocene marine hydrocarbon source rocks in deep-water area in Qiongdongnan Basin of northern South China Sea 被引量:3
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作者 LI Wenhao ZHANG Zhihuan +1 位作者 LI Youchuan FU Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第5期107-114,共8页
Drilling wells reveal that the organic matter abundance of Miocene marine source rocks in shallow water area of the Qiongdongnan Basin is relatively low with poor hydrocarbon generation poten- tial. However, in some d... Drilling wells reveal that the organic matter abundance of Miocene marine source rocks in shallow water area of the Qiongdongnan Basin is relatively low with poor hydrocarbon generation poten- tial. However, in some drilling wells of deep water area close to the central depression belt, Miocene marine source rocks with better organic matter abundance and hydrocarbon generation have been found, which have achieved better source rock standard based on the analysis of geochemical charac- teristics. Although there are no exploratory wells in deep water area of the research region, through the comparative analysis of geochemical data of several typical exploratory wells respectively from shallow water area in the basin, central depression belt margin in deep-water area of the basin and Site 1148 of deep sea drilling in the South China Sea Basin, it reveals that the tendency of the quality of source rocks becomes positive gradually from delta to bathyal environment, which then becomes negative as in deep oceanic environment. Owing to the lack of terrestrial organic matter input, the important controlling factors of Miocene marine source rocks in the Qiongdongnan Basin are ocean productivity and preservation conditions of organic matter. The element geochemistry data indicate that the tendency of the paleoproductivity and the preservation conditions of organic matter become positive as water depth increase from shallow area to bathyal area close to central depression belt. So it is speculated that there must exist high quality source rocks in the central depression area where the preservation conditions of organic matter are much better. Besides, in theory, in oxygen-poor zone of oceanic environment at the water depth 400–1 000 m, the preservation conditions of organic matter are well thus forming high-quality marine source rocks. The result- ing speculation, it is reasonable to consider that there are high hydrocarbon generation potential source rocks in bathyal environment of the Qiongdongnan Basin, especially at the water depth 400– 1 000 m. 展开更多
关键词 hydrocarbon-generation potential marine source rocks ocean productivity preserva- tion condition deep water area deep sea drilling
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Genotoxicity evaluation of drinking water sources in human peripheral blood lymphocytes using the comet assay 被引量:2
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作者 WU Yulin CHEN Haigang +4 位作者 LI Zhaoli SUN Liwei QU Mengmeng LI Mei KONG Zhiming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期487-491,共5页
The potential harm of organic pollutants in drinking water to human health is widely focused on in the wodd; more and more pollutants with genotoxic substances are released into the aquatic environment. Water source s... The potential harm of organic pollutants in drinking water to human health is widely focused on in the wodd; more and more pollutants with genotoxic substances are released into the aquatic environment. Water source samples were collected from 7 different localities of Nanjing City. The potential genotoxicity of organic extracts from drinking water sources were investigated by means of the comet assay in human peripheral lymphocytes. The results showed that all the organic extracts from all the water source samples could induce DNA damages of human peripheral blood lymphocytes at different levels. A significant difference (P 〈 0.01) was observed when compared with the solvent control, The DNA damage increased with the increase of the dosage of the original water source. Significant differences of DNA damage were observed in different drinking water sources, as shown by the multiple comparisons analysis at the dosage of 100x; the degree of DNA damage treated by Hushu waterworks (at town level) was the most serious, the arbitrary units (AU) was 141.62±6.96, however, that of Shangyuanmen waterworks (at city level) was only 109.64±2.97. The analysis also revealed that the genotoxicity of town's water sources was higher than that of the city. The results demonstrated that the comet assay can be successfully applied to the genotoxicity monitoring programs of drinking water sources. 展开更多
关键词 comet assay drinking water sources GENOTOXICITY human peripheral blood lymphocyte
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Exploitation of groundwater resources and protection of wetland in the Yuqia Basin 被引量:3
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作者 ZHANG Chun-chao LI Xiang-quan +4 位作者 GAO Ming HOU Xin-wei LIU Ling-xia WANG Zhen-xing MA Jian-fei 《Journal of Groundwater Science and Engineering》 2017年第3期222-234,共13页
In Yuqia Basin, the climate is arid and the ecologic environment is fragile, and shortage of water resources has seriously restricted the sustainable development of local economy. In order to meet the needs of industr... In Yuqia Basin, the climate is arid and the ecologic environment is fragile, and shortage of water resources has seriously restricted the sustainable development of local economy. In order to meet the needs of industrial and domestic water in the Yuqia Basin, numerical simulation was used to evaluate the groundwater resources and potential for exploitation. The results showed that the mathematical model and calculation parameters used were mainly in accordance with practical situation. The calculated value of the underground water level is consistent with measured value during the period of identification and validation. The total recharge of groundwater resources was 22.02×10~4 m^3/d, and the total drainage was 21.95×10~4 m^3/d at present. The Yuqia River leakage is the main supply source of groundwater. There is no significant effect on area of wetland when water source place exploited by 2.5×10~4 m^3/d at alluvial-diluvial fan of Yuqia River. After long-term exploitation, the spring flow reduces from 1.42×10~4 m^3/d to 1.01×10~4 m^3/d and wetland area reduces by 32.7% of original area. The calculation of water balance shows that it is safe to the Yuqia Basin, Da Qiadam Lake, the Mahai Basin at downstream of Yuqia River and wetland under the condition of water source place exploited by 2.5×10~4 m^3/d. 展开更多
关键词 Yuqia Basin Groundwater resources Numerical simulation water source WETLAND
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Establishment of water source discrimination model in coal mine by using hydrogeochemistry and statistical analysis: a case study from Renlou Coal Mine in northern Anhui Province, China 被引量:5
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作者 SUN Lin-hua GUI He-rong 《Journal of Coal Science & Engineering(China)》 2012年第4期385-389,共5页
The demand for energy consumption promotes to find more coal in deep underground up to 1 000 m and brings more serious situation of water disaster. As one of the major methods for water disaster control, hydrogeochemi... The demand for energy consumption promotes to find more coal in deep underground up to 1 000 m and brings more serious situation of water disaster. As one of the major methods for water disaster control, hydrogeochemistry attracts a series of studies related to water source discrimination. In this paper, a simple method for constructing the water source discrimination model based on major ions and multivariate statistical analysis was reported using the following procedures: (1) collection of data and interpretation, (2) analysis of controlling factors based on the chemical composition of groundwater, (3) "pure" sample chosen, and (4) discrimination model establishment. After the processes, two functions and a diagram were established for three aquifers (the Quaternary, Coal bearing, and Taiyuan Fm.) from the Renlou Coal Mine in northern Anhui Province, China. The method can be applied in almost all coal mines and can be used for evaluating the contribution ratios if the water is collected from a mixing source. 展开更多
关键词 HYDROGEOCHEMISTRY water source discrimination multivariate statistical GROUNDwater
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