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water quality evaluation based on improved fuzzy matter-element method

Journal of Environmental Sciences 2012年第7期24卷 1210-1216页

作者： Dongjun Liu Zhihong Zou School of Economics and Management Beihang UniversityBeijing 100191China

For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.

关键词： water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership Key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership

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water quality and habitat drive phytoplankton taxonomic and functional group patterns in the Yangtze River

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Ecological Processes 2024年第1期13卷 144-158页

作者： Wenqi Gao Fangyuan Xiong Ying Lu Wei Xin Haihua Wang Gangpeng Feng Chiping Kong Lei Fang Xiaoping Gao Yushun Chen State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences Jiangxi Institute for Fisheries Sciences Poyang Lake Fisheries Research Centre of Jiangxi Province East China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Jiujiang Institute of Agricultural Sciences

Background Although phytoplankton are important primary producers in food webs, they are relatively less studied in large rivers compared to other types of systems. To fill this research gap, we studied phytoplankton taxonomic and functional composition and their relationships with water quality, habitat, climate, and land use across 30 river sections in the middle and lower reaches of the Yangtze River during 2017–*** Major observed phytoplankton groups were cyanobacteria, bacillariophyta, and chlorophyta. Phytoplankton total abundance, total biomass, and species richness significantly decreased in the dry season compared to the wet season, with the species and functional composition differing significantly between seasons. Phytoplankton species differences between seasons were mainly contributed by Oscillatoria sp., Pseudanabaena sp., and Melosira granulata. The dfferences in phytoplankton functional groups between seasons were mainly contributed by P（including Closterium sp., Melosira sp.）, Lo（including Merismopedia sp., Peridinium sp., Ceratium sp., and Gymnodinium sp.）, and J（including Pediastrum sp., Tetraedron sp., Crucigenia sp., Scenedesmus sp., and Coelastrum sp.）. The variance partitioning showed that water quality（NO3-N, total suspended solids, turbidity） and habitat（water flow, river bank and river channel conditions） were critical factors in shaping phytoplankton patterns, followed by climate and land *** Results indicated that there was significant seasonal variation of phytoplankton in the Yangtze River, with water quality and habitat primarily driving phytoplankton patterns. Our study contributes to the understanding of natural and anthropogenic factors that drive seasonal successional processes of phytoplankton in the Yangtze River. These findings have important implications for environmental management as well as towards the ecological restoration of large rivers.

关键词： Yangtze River Phytoplankton Functional group water quality Physical habitat

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water quality characteristics along the course of the Huangpu River (China)

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Journal of Environmental Sciences 2007年第10期19卷 1193-1198页

作者： YANG Hong-jun SHEN Zhe-min ZHANG Jin-ping WANG Wen-hua School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Xuhui District Environmental Protection Bureau Shanghai 200030 China Shanghai Environmental Monitoring Center Shanghai 200030 China

Huangpu River is about 114.5 km from upriver Dianfeng to downriver Wusong, near the estuary of the Yangtze River. It plays a key role in supplying water for production, life, shipment and irrigation. With the industrial development, the pollution of the Huangpu River has become serious recently. The biological oxygen demand （BOD）, total nitrogen （TN）, total phosphorus （TP）, oil, phenol and suspended solids （SS） were lower in the upstream sites than in the downstream sites, indicating pollutants being input along its course. water quality was the worst in the Yangpu site, near the center of Shanghai City. Dissolved oxygen （DO） content was less than 2 mg/L in the site of Yangpu in July. Among relations between thirteen characteristics, relations between BOD, DO, TN, TP, NH4^＋ -N, NO3^- -N and the count of total bacteria or Escherichia coli were significant and interdependent. Inner relationships between these main characteristics in the Huangpu River were studied. High nutrient concentration led to growth of microorganisms, including E. coli. Degradation of organic matters and respiration of bacteria made oxygen concentration decreased in the water body, and DO was a key factor for nitrification-denitrification process of nitrogen. In the Yangpu site, DO was decreased to less than 3.0 mg/L with BOD higher than 7.5 mg/L in May and July. Low DO concentration will decrease nitrification rate. Nitrification need at higher DO value than other organic substrate oxidation. Consequently, river water contains low NO3^- -N values with high amounts of TN and NH4^＋ -N there. This will block the self-purification of surface water, by decreasing the rate of nitrification-denitrification transformation process in the water body.

关键词： water quality ecological assessment Huangpu River nitrification

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water quality, habitat, and fish assemblage relationships in middle-order agriculture and forest streams of the Mississippi Alluvial Plain

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Ecological Processes 2024年第1期13卷 217-236页

作者： Matthew L.Skoog Michael A.Eggleton Yushun Chen Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Minnesota Department of Natural Resources State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

Background Agriculture has greatly influenced water quality, habitats, and fish assemblages in streams of the Mississippi Alluvial Plain(MAP) ecoregion. However, MAP streams have historically been understudied compared to streams in other agricultural regions of the USA. In this study, water quality, habitat, and fish assemblage composition were assessed seasonally(spring, summer, and fall) in eight representative MAP streams located across three U.S. states. The study design included four streams containing highly agricultural watersheds(herein termed “agriculture” streams) and four streams containing mostly forested watersheds(herein termed “forest” streams), which were intended to represent reference conditions for MAP *** In general, forest streams contained significantly better instream and riparian habitats than agriculture streams(P = 0.010–0.040) whereas agriculture streams contained significantly greater levels of primary nutrients(P water nutrient concentrations, and benthic chlorophyll-a production. Structurally, fish assemblages in both stream types contained many regionally common species, though some species appeared to exhibit affinities for a particular stream type. Functionally, fish assemblages in agriculture streams contained more tolerant species, more omnivores, and fewer insectivores compared to forest stream assemblages, which were nearly all insectivores. Overall, one-third of the fish specimens collected in forest streams classified as intolerant *** Our results suggested that stream water quality, habitat, and fish assemblages differed between agriculture and forest streams in the MAP, with fish assemblages e

关键词： Agriculture Stream Land use water quality Habitat Fish Multivariate statistics Mississippi Alluvial Plain

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water quality MODELING AND POLLUTION CONTROL FOR THE EASTERN ROUTE OF SOUTH TO NORTH water TRANSFER PROJECT IN CHINA

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Journal of Hydrodynamics 2006年第3期18卷 253-261页

作者： WANG Chao WANG Yan-ying WANG Pei-fang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes College of Environmental Science and Engineering Hohai University Nanjing 210098 China

South to North water Transfer Project in China is the largest project over centuries to solve the water shortage problem in vast areas of northern China. It comprises of three routes： the eastern, central and western route and this study mainly focused on the eastern route. As water quality is the key factor for the eastern route, this paper examined the main factors influencing water quality of the main route south of the Yellow River, by investigating the point source, non-point source （diffusive source） and internal source pollutions along the main eastern route and in its drainage basins, and assessing the Current water quality in the waterways. According to the complicated and combined systems of rivers and lakes in this route, one-dimensional water quantity and quality model for rivers and two-dimensional model for lakes were developed to simulate the hydrodynamic and pollutant transport processes. The numerical method and model algorithm were described. The values of model parameters were estimated by using field-monitoring data along the main route and the inverse modeling technique. Established models were employed to predict the degradations of CODMn and NH4^＋-N in the main stream, under the conditions of current pollution loads and different hydrologic conditions. Schemes were present for controlling total quantities of pollutants from point source and non-point source along the main route to secure water quality for the eastern route.

关键词： South to North water Transfer Eastern RouteProject water quality pollution loads pollution control

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water quality, nutrient budget, and pollutant loads in Chinese mitten crab (Eriocheir sinensis) farms around East Taihu Lake

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Chinese Journal of Oceanology and Limnology 2012年第1期30卷 29-36页

作者：蔡春芳谷孝鸿黄鹤忠戴修赢叶元土施陈江 School of Basic Medicine and Biological Science Soochow University Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

To understand the factors causing frequent outbreaks of harmful algae blooms in the Taihu Lake, China, we studied water quality and nutrient budget in Chinese mitten crab (Eriocheir sinensis) farm ponds in the eastern part of the lake from November 2007 to December 2009. We estimated the nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) loads. Materials input and output ponds, water exchange, and applied management practices of 838.5-hm2 crab ponds were surveyed using questionnaires. water quality of 12 ponds, which were located no more than 2 km from East Taihu Lake, were monitored. The results show that water quality in the crab ponds was better than reference data. Feeds, including corn seed, commercial feed, trash fish, and gastropod, were the major sources of N and P input in the crab ponds, contributing 88.7% and 94.9%, respectively. In total, 60.5% of N and 37.3% of P were sequestered by macrophytes, and only 15.7% and 8.5% of them were discharged as effluent. The net loads of N and P in effluent were 16.43 kg/hm2/cycle and 2.16 kg/hm2/cycle, respectively, while the COD load was -17.88 kg/hm2/cycle. This indicated that crab farming caused minor negative impact on the trophic status of the lake area, which was attenuated by macrophytes. However, wastewater purification is still necessary in crab faming.

关键词： Chinese mitten crab (Eriocheir sinensis) water quality mass budget pollutant load Taihu Lake

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water quality assessment of benthic diatom communities for water quality in the subalpine karstic lakes of Jiuzhaigou,a world heritage site in China

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Journal of Mountain Science 2016年第9期13卷 1632-1644页

作者： OUYANG Li-li PAN Yang-dong HUANG Cheng-min TANG Ya DU Jie XIAO Wei-yang Department of Environmental Science and Engineering Sichuan UniversityChengdu 610065China Department of Environmental Science and Management Portland State UniversityPortlandOR 97207USA Jiuzhaigou Administrative Bureau Jiuzhaigou County 623400China Chengdu Academy of Environmental Sciences Chengdu 610072China.

Jiuzhaigou, characterized by its magnificent waterscapes and subalpine karstic features, is both a World Heritage Site and a World Biosphere Reserve in southwestern China. In recent years, this unique ecosystem has shown signs of stress due to increasing tourism activities within the reserve. The various routine methods, which monitor physical and chemical properties, do not fully reflect water quality in the subalpine and alpine lakes, while the indicators using aquatic organisms to evaluate the water quality or status of the subalpine lakes are poorly reported. Thus, in this study, benthic diatoms from multiple habitats in Jiuzhaigou were sampled and assessed for water quality monitoring. Canonical Correspondence Analysis （CCA） showed that the canonical coefficients for elevation, water temperature and total nitrogen on the first Canonical Corresnondence Analysis axis were -0.84. 0.78 and -0.53, respectively, environmental variables associated with the distribution patterns of benthic diatoms. The dominance of diatom taxa indicative of nutrient enrichment indicates a clear trend toward eutrophication in the Pearl Shoal and Colorful Lake, two of the sites mostly visited by tourists. It was observed that the effect of the type of substratum on diatom community composition is not significant in subalpine lakes. The most dominant species in Jiuzhaigou lakes are the genera Achnanthes, Fragilaria, CymbeUa, Cocconeis, Diatoma and Denticula. In combination with dominant and sensitive species in the benthic diatom communities, CCA and CA methods can be used to evaluate the impact of human activities on subalpine karstic lakes. The dominance of diatom taxa is indicative of nutrient enrichment and the results of CCA and CA indicate a clear trend toward eutrophication in the Pearl Shoal and Colorful Lake, two of the sites mostly visited by tourists.

关键词： Subalpine karstic lakes water quality Benthic diatoms Community composition Canonicalcorrespondence analysis

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water quality, agriculture and food safety in China:Current situation, trends, interdependencies, and management

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Journal of Integrative Agriculture 2015年第11期14卷 2365-2379页

作者： ZHANG Xiao-nan GUO Qiu-ping SHEN Xiao-xue YU Sheng-wen QIU Guo-yu Shenzhen Engineering Laboratory for water Desalinization with Renewable Energy School of Environment and EnergyPeking University Chinese Academy for Environmental Planning

water quality in China is becoming a severe challenge for agriculture and food safety, and it might also impact health of population via agriculture and food. Thus, it is causing widespread concern. Based on extensive literatures review and data mining, current situation of water pollution in China and its effects on food safety were analyzed. The 2nd National water Resource Survey in China show that the surface water all over the country was under slight pollution and about 60% of groundwater is polluted. Drinking water quality is basically guaranteed in urban area but it is worrisome in rural areas. In addition, China is the largest consumer of fertilizer and pesticide in the world and the amounts of application still show increasing trends. Fertilizers and pesticides are the most important sources of pollution, which affect human health as persistent organic pollutants and environmental endocrine disruptors. Eutrophication of surface water and nitrate pollution of groundwater are serious threats to drinking water safety. Sewage irrigation is becoming a pollution source to China＇s water and land because of lacking of effective regulations. Although, with the advance in technology and management level, control of nitrogen and phosphorus emissions and reducing water pollution is still a major challenge for China.

关键词： agriculture drinking water eutrophication fertilizer food safety groundwater heavy metals microcystin nitrate pesticide pollution water quality

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water quality Assessment of the River Nile System:An Overview

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Biomedical and Environmental Sciences 2004年第1期17卷 87-100页

作者： RIFAAT A.WAHAAB MOHAMED I.BADAWY National Research Center DokkiCairoEgyptNational Research CenterDokkiCairoEgypt

Objectives The main objective of the present article is to assess and evaluate the characteristics of the Nile water system , and identify the major sources of pollution and its environmental and health consequences. The article is also aimed to highlight the importance of water management via re-use and recycle of treated effluents for industrial purpose and for cultivation of desert land. Method An intensive effort was made by the authors to collect, assess and compile the available data about the River Nile. Physico-chemical analyses were conducted to check the validity of the collected data. For the determination of micro-pollutants, Gas Chromatography (GC) and High Performance Liquid Chromatography (HPLC) were used. Heavy metals were also determined to investigate the level of industrial pollution in the river system. Results The available data revealed that the river receives a large quantity of industrial, agriculture and domestic wastewater. It is worth mentioning that the river is still able to recover in virtually all the locations, with very little exception. This is due to the high dilution ratio. The collected data confirmed the presence of high concentrations of chromium and manganese in all sediment samples. The residues of organo-chlorine insecticides were detected in virtually all locations. However, the levels of such residues are usually below the limit set by the WHO for use as drinking water. The most polluted lakes are Lake Maryut and Lake Manzala. Groundwater pollution is closely related to adjacent (polluted) surface waters. High concentrations of nutrients, ***, sulfur, heavy metals, etc. have been observed in the shallow groundwater, largely surpassing WHO standards for drinking water use. Conclusion A regular and continuous monitoring scheme shall be developed for the River Nile system. The environmental law shall be enforced to prohibit the discharge of wastewater (agricultural, domestic or industrial) to River Nile system.

关键词： water quality River Nile Lakes Pollution sources Assessment

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water quality impacts of small-scale hydromodification in an urban stream in Connecticut, USA

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Ecological Processes 2018年第1期7卷 106-115页

作者： Bin Zhu Daniel S.Smith Anthony P.Benaquista Dylan M.Rossi Betsy M.Kadapuram Man Lok Yu Andrew S.Partlow Nathan R.Burtch Department of Biology University of Hartford200 Bloomfield AvenueWest HartfordCT 06117USA College of Marine and Environmental Sciences James Cook University1 James Cook DriveTownsvilleQLD 4811Australia Department of Geography and Environmental Planning Towson University8000 York RoadTowsonMD 21252USA

Introduction:Construction activities in and along urban streams increase the sediment input into surface waters,causing an overall decline in water quality and aquatic *** this case study,we investigate the water quality impacts of local hydromodification in an urban stream(discharge 0.4 m^(3)/s).At the site of interest,workers removed a stream crossing consisting of an embankment with culverts and replaced it with a small bridge(single span of 25 m)in an effort to improve flow ***:water samples were taken at four sites along the North Branch Park River in Connecticut,Northeastern United *** and dissolved oxygen(DO)were measured in situ,and nitrate and total phosphorus(TP)were measured in the *** macroinvertebrate samples were also collected and analyzed for taxon richness and Shannon-Weaver species *** were compared between upstream and downstream sites and before,during,and after *** used one-way ANOVA combined with the post hoc Turkey test to derive statistical ***:During construction,turbidity increased temporarily by 60.9%[from 2.48 Nephelometric Turbidity Units(NTU)over ambient to 4.00 NTU].Once construction was completed,DO increased locally from 11.0 to 13.0 mg/*** macroinvertebrate taxon richness and species diversity declined by 61.6 and 32.6%respectively,with no recovery observed in the year following *** quality was only affected within 50 m *** and TP concentrations were ***:Small-scale hydromodification temporarily increased the turbidity as a result of increased sediment input,approaching the maximum level for clean water(5 NTU).Benthic macroinvertebrate communities declined in the immediate downstream vicinity of construction but are expected to recover soon given that turbidity recovered to pre-construction levels,and DO *** outcomes emphasize that environmental assessment is important not

关键词： Urban streams Pollution Hydrologic services water quality Benthic macroinvertebrates North Branch Park River

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