Assessment of Point and Nonpoint Sources Pollution in Songhua River Basin,Northeast China by Using Revised Water Quality Model

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.

Analysis of Pollution Sources and Countermeasures against Water Pollution in a Small River Basin of Chaohu Lake——A Case Study of the Shiwulihe River

The Shiwulihe River, the inflow river of Chaohu Lake in Hefei City, was taken as an example. Based on the current status of water quali- ty and analysis of pollution sources in the Shiwulihe River, countermeasures and suggestions of controlling water pollution were proposed to provide effective ways for the control of water pollution and restoration of aquatic ecosystem in the Shiwulihe River and other similar rivers flowing into lakes.

Analysis on the Status of Agricultural Non-point Source Pollution in Xinan River Basin

Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and poultry breeding and rural domestic pollution on non-point source TN and TP.At last,some technical countermeasures of controlling non-point source pollution were put forward according to the characteristics of agricultural non-point source pollution in Xinan River basin.

A distributed non-point source pollution model: calibration and validation in the Yellow River Basin

The applicability of a non-point source pollution model—SWAT(soil and water assessment tools) in a large river basin with high sediment runoff modulus(770 t/km2 in the Yellow River) was examined. The basic database, which includes DEM, soil and landuse map, weather data, and land management data, was established for the study area using GIS. A two-stage “Brute Force' optimization method was used to calibrate the parameters with the observed monthly flow and sediment data from 1992 to 1997. In the process of calibration automated digital filter technique was used to separate direct runoff and base flow. The direct runoff was firstly calibrated, and the base flow, then the total runoff was matched. The sediment yield was calibrated to match well. Keeping input parameters set during the calibration process unchanged, the model was validated with 1998—1999's observed monthly flow and sediment. The evaluation coefficients for simulated and observed flow and sediment showed that SWAT was successfully applied in the study area: relative error was within 20%, coefficient of determination and Nash-Suttcliffe simulation efficiency were all equal to or above 0.70 during calibration and validation period.

Research on the Influence of Land Use Changing on Non-point Source Pollution in Heihe River Basin

Based on the exploring of SWAT model suitability in Hei River Basin, this paper analyze quantitatively and compare non-point source pollution loads occurred under different land use scene. At last, the following conclusion can be attained： （1） Land use change exerts tremendous influence on non-point source pollution. Since forest land can save water and reduce soil loss, which decreases greatly the source of non-point source pollution; （2） Strengthening land management and promoting reasonable land use, especially the over 15 degree slope farmland, will be the effective measure to control non-point source pollution and protect the quality of water in the Hei River basin; （3） The best land use situation in Hei River basin should be like the following modes： complying with national water source protection policy, gradual evacuation of river basin population, returning all the sloping farmland which is above 15 degree to forest land, allowing the existence of few farming land below 15 slope degree on the premise that the drinking water quality standard is reached, no unused land, good vegetation covering situation. At then, total nitrogen load is 13.25 kg, total phosphate load is 3.29 kg, which means it will not contaminate

Research and Application of Pollution Control in the Middle Reach of Ashe River by Multi-Objective Optimization

Based on one-dimensional water quality model and nonlinear programming, the point source pollution reduction model with multi-objective optimization has been established. To achieve cost effective and best water quality, for us to optimize the process, we set pollutant concentration and total amount control as constraints and put forward the optimal pollution reduction control strategy by simulating and optimizing water quality monitoring data from the target section. Integrated with scenario analysis, COD and ammonia nitrogen pollution optimization wasstudiedin objective function area from Mountain Maan of Acheng to Fuerjia Bridge along Ashe River. The results showed that COD and NH3-N contribution has been greatly reduced to AsheRiverby 49.6% and 32.7% respectively. Therefore, multi-objective optimization by nonlinear programming for water pollution control can make source sewage optimization fairly and reasonably, and the optimal strategies of pollution emission are presented.

Develop an Air Emission Inventory for Potential Point Sources in Northern Key Economic Zone and Simulate Its Impacts on Air Quality in Hanoi City,Vietnam

The Northern Key Economic region of Vietnam is a dynamic economic center that is an important economic locomotive of the North and the whole of Vietnam.In this area,large industrial parks are concentrated,attracting many large FDI projects.Key industries:cement production,cars-motorcycles,electronics,...Economic development entails environmental problems.The industrial sector has been identified as the number one driving force driving the growth of Hanoi city and neighboring provinces.Therefore,industrial development is one of the main causes of environmental pollution.In addition,the growth rate of industry in neighboring provinces significantly affects the air quality in Hanoi city.Some factories in Vinh Phuc,Hung Yen,Bac Ninh and Hai Duong provinces have large sources of gas emissions,potentially affecting air quality around Hanoi city.Monitoring results show that air pollution in Hanoi city is mainly caused by dust pollution,especially PM2.5 superfine dust.This is a very harmful dust to health;it is necessary to determine the cause and control solution.Therefore,the objectives of this study are:(1)inventory of potential emissions sources for industrial activities in the northern key economic region around Hanoi;(2)Simulate air spread by AERMOD model to get an overall picture of the industrial impact of surrounding provinces in Hanoi city;(3)Propose solutions to manage air quality for the city in the coming time.Simulation results for pollutants with the highest concentration of NOx for 1 hour,24 hours and the average of the year is 7.94;1.02;0.222(μg/m3);of CO for 1 hour and 8 hours are 27.616;8.89(μg/m3);of SO2 for 1 hour,24 hours and the average of the year is 4.005;0.288;0.038(μg/m3);of PM2.5 for 1 hour,24 hours and the average of the year is 0.32;0.023;0.003(μg/m3);of PM10 in 1 hour,24 hours and year average are 1.03;0.074;0.098(μg/m3).

Analysis on Strategic Future of Application of Agricultural Ecological Source in Control on Agricultural Nonpoint Source Pollution in Xi River Area in Guangxi

Non-point source pollution has become a hot issue on aquatic ecological environment at home and abroad. The research analyzed the challenges confronted by Xi River and proposed to construct agricultural ecological source in middle and upper reaches of the Xi River from the perspectives of scientific layout, legal construction, routine monitoring, technology integration, and coordination system in order to promote sustainable development of eco-environment in Xi River.

Method for calculating non-point source pollution distribution in plain rivers

The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source pollution from cells is estimated using the export coefficients of different land use types. The non-point source pollution from a land cell should all go into the closest fiver reach, so it is distributed according to the terrain of the plain river network area and the positions of land cells and river network reaches. A relationship between a single land cell and its pollution-receiving reach can be determined using this system. In view of the above, a spatial distribution model of the rainfall runoff and non-point source pollution in reaches of a plain river network area was established. This model can provide technological support for further research on the dynamic effects of non-point source pollution on water quality.

Water Quality Assessment of the River Nile System:An Overview

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, E.coli, 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.

Application of Index Analysis to Evaluate the Water Quality of the Tuul River in Mongolia

A study of water pollution determinands of the Tuul River was carried out in surrounding area of Ulaanbaatar, the capital of Mongolia at 14 monitoring sites, using an extensive dataset between 1998 and 2008. An index method, developed by Ministry of Nature and Environment of Mongolia, applied for assessment and total, seven hydro-chemicals used in the index calculation. The research indicates that the Tuul River is not polluted until the Ulaanbaatar city and the contamination level spike appears when the river entering the city. The upper reaches of the river and tributaries have relatively good quality waters. Several pollution sources exist in the study area. Among them, the Central Wastewater Treatment Plant (CWTP) is a strongest point source in the downstream section of the river, recently. Pollutions at sites 7-10 are strongly dependant effluent treatment levels from the plant, and it contains a high amount of chemicals that can cause of major decrement of the water quality. This would definitely kill aquatic fauna in the stretch of the river affected. It certainly happened in 2007. The general trend of water quality gradually has been decreased in the study period. Clearly, there is a need to improve the water quality in the Tuul River in surrounding area of the Ulaanbaatar. In order to change this situation, operation enhancement of treatment plants, a water quality modeling and artificial increment of dissolved oxygen concentrations become crucial to improve the water quality significantly. Perhaps a new wastewater treatment plant is needed for Ulaanbaatar city.

Application of SWAT Model to Non-point Source Pollution in Xincai River Basin

[Objective]The study aimed to simulate the production and transportation process of surface runoff,sediment and non-point source pollution in Xincai River basin based on SWAT model.[Method]On the basis of analyzing the principles of SWAT model,the correlative parameters of runoff,sediment and water quality were calibrated,then the spatial and temporal distribution of runoff,sediment and non-point source pollutants in Xincai River basin were studied by using SWAT model.[Result]The results of calibration and validation showed that SWAT model was reasonable and available,and it can be used to simulate the non-point source pollution of Xincai River basin.The simulation results revealed that the load of sediment and various pollutants was the highest in the rainy year,followed by the normal year,while it was the minimum in the dry year,indicating that the production of sediment and non-point source pollutants was closely related to annual runoff.[Conclusion]The research could provide scientific references for the prevention of non-point source pollution in a basin.

THE FLUX OF LAND-BASED SOURCE POLLUTANTS FROM TUMEN RIVER SYSTEM ENTERING THE SEA OF JAPAN

The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and economic development in the Tumen River basin. Pollutant type and primary pollution factor of the Tumen River in Northeast China is described by weighted coefficient method in this paper. The results indicate that the river is organic pollution type and primary pollution factor is COD. Fresh water fraction proves that the estuary is not affected by tide cycle. COD annual flux entering the Sea of Japan calculated by zero dimension model in 1993 was 90.50 ×10 3 tons. It is estimated with emission coefficient method that the COD will be 176.4 ×10 3 and 458.6 ×10 3 tons for the years of 2000 and 2010 respectively.

长江下游干流沉积物重金属特征及生态风险评价

【研究目的】长江下游干流沿岸分布众多取水口,为保障用水安全和生态环境健康,亟需了解近岸沉积物中重金属相关现状。【研究方法】调查过程中自上而下分左右岸共采集沉积物样品85组,利用描述统计分析重金属含量特征,综合相关性分析和主成分分析探讨重金属来源,采用地累积指数法、污染负荷法分析重金属污染程度,并评估其潜在生态风险。【研究结果】平均含量由高至低为Zn>Cr>Cu>Ni>Pb>As>Cd;上游至下游,Cu、Zn、Cr、Ni呈小幅波动增加趋势,As、Pb呈小幅波动下降趋势,Cd呈较大波动下降趋势;Cd的污染程度最重,主要来源于农业生产等人类活动,1~4级污染分别占比1.18%、1.18%、18.82%和34.12%,Cr和Ni为无污染,主要是工业生产源和地球化学自然源;中等污染程度(1≤PLI_(point)<2)的样点占比34.18%,潜在生态风险指数(RI)为19.48~388.62,轻微潜在生态风险、中等潜在生态风险、强潜在生态风险和极强潜在生态风险占比分别为38.82%、42.35%、17.65%和1.18%。【结论】长江下游干流沉积物中重金属含量较低,流域整体处于轻微—中等风险的无污染状态(PLI_(area)<1),右岸重金属平均含量、污染程度和潜在生态风险均普遍高于左岸。

贵州裸露型岩溶地下河系统污染防治技术——以遵义坪桥地下河系统污染防治工程为例

裸露型岩溶区岩溶强发育、水文地质条件复杂,受污染的地下河系统通道隐蔽性强、污染防治难度大。本文以坪桥地下河系统污染防治工程为例,在近污染源的主径流通道实施“地下水防渗帷幕+污水抽排”工程措施实现近源截排。施工面临岩溶破碎地层易掉块卡埋钻、钻效低及岩溶强发育段浆液扩散距离远等难题。通过配备适宜的钻进工艺,采取纯压式灌浆、水泥砂浆灌填溶洞、低压限量及速凝浆液灌注等灌浆控制措施,保证了工程进度质量,实现了源头治理污染地下水的目的。“近源截排”对类似水文地质条件下地下水污染防治提供可借鉴的地学治理模式。

基于冗余分析的成都市府河缓冲带土地利用对水质的影响

土地利用是影响河流水环境质量的重要因素之一。然而,大型城市河流缓冲区的土地利用类型及组成对河流水质的影响方式仍不清晰。选取成都市中心城区的府河及其支流作为研究对象,设置17个水质监测断面,于2018年1月—2019年12月对COD_(Mn)、NH_(4)^(+)-N和TP 3个水质指标开展连续监测。同时,还获得了相同时段内的降水数据和基于高分卫星(GF-1)影像解译的土地利用数据。在此基础上,利用空间分析以及冗余分析方法,探讨河岸缓冲区内土地利用结构、组成对府河及支流水质的影响。研究结果表明:选取河段从上游到下游的COD_(Mn)、NH_(4)^(+)-N和TP浓度均呈增加趋势,这3类污染物在上游第一个监测断面浓度依次为1.73、0.26、0.06 mg/L,到下游最后一个监测断面浓度为2.59、0.97、0.15 mg/L。相对于干流,府河支流污染物浓度无明显空间分布特征。从时间上看,6—9月水体中各污染物浓度相对较高。基于冗余分析的结果发现,在河段2 000 m缓冲区范围内的土地利用类型对水质的影响最明显,校正后的解释度达57%,表明河段内污染物质主要源于此区域。该范围内,建设用地与其他生产用地可能是COD_(Mn)与NH_(4)^(+)-N的主要源区,农业用地是TP的主要来源,生态用地对于COD_(Mn)与NH_(4)^(+)-N具有一定的吸收分解作用。但是,研究区生态用地以园林绿化用地为主,需要施用磷肥,可能成为水体TP的重要贡献源。因此,合理规划河流2 000 m缓冲范围内的建设用地与生态用地比例,控制园林绿化用地的施肥用量,是保障成都市城市河流水环境安全的重要途径。

基于ReNuMa模型的武烈河氮磷负荷模拟及来源解析

武烈河是承德市工农业及居民生活用水的重要水源,开展流域污染物负荷模拟及来源解析对流域水污染控制和管理具有重要意义。采用ReNuMa模型对武烈河磷矿上游断面子流域2015—2020年的水文径流过程和全流域2018—2020年的总氮(TN)、总磷(TP)污染负荷量进行模拟,解析氮磷负荷的来源及贡献率。结果表明:(1)2018—2020年,年均TN负荷量为655.98 t,各污染来源贡献率由大到小依次为地下水(30.68%)>点源(25.63%)>腐生系统(25.16%)>沉积物源(12.85%)>地表径流(5.68%);2018—2020年,年均TP负荷量为8.12 t,各污染来源贡献率由大到小依次为沉积物源(49.58%)>点源(16.54%)>地下水(15.01%)>腐生系统(13.20%)>地表径流(5.67%)。(2)年内氮磷污染负荷入河量以非点源为主,分别占总负荷的74.37%和83.46%,点源与非点源的贡献占比受汛期和非汛期影响显著,非汛期以点源形式输入的负荷占比远超汛期(6—9月)的。本研究结果能够为流域水质改善和污染管控方案的制定提供借鉴。

基于SWAT模型的武强溪流域非点源污染关键源区界定与控制策略

随着点源污染的控制与处理技术日趋完善,非点源污染成为重要的水污染源。武强溪作为流入千岛湖的第二大支流,量化武强溪流域非点源污染负荷,解析非点源污染时空分布特征,提出适合削减武强溪流域污染物的最佳管理措施(best management practices,BMPs)对千岛湖水污染高效治理至关重要。该研究基于土壤水分评估工具(Soil and water assessment tool,SWAT)分析了武强溪流域径流量、总氮输出负荷量的时空分布特征,探究了不同管理措施及组合的削减效果,提出了武强溪流域非点源污染针对性的治理措施。结果表明:1)SWAT模型对于武强溪流域径流量和总氮输出负荷量的模拟具有较好的适用性,径流量校准期和验证期的决定系数(coefficient of determination,R^(2))分别为0.86、0.97,纳什系数(nash-sutcliffe coefficient,NSE)分别为0.83、0.96,百分比偏差(percent bias,PBIAS)分别为15.8%、-6.3%,总氮校准期和验证期的决定系数分别为0.87、0.74,纳什系数分别为0.63、0.66,百分比偏差分别为31.6%、21.2%;2)该流域径流量和总氮负荷主要集中在3—7月,分别占全年输出量的71.67%和75.76%。综合考虑氮的来源和流失途径,将耕地和林地面积占比大、坡度陡的子流域设置为总氮的关键污染源区。考虑调整化肥施用量/配方、改变耕作方式和设置植被缓冲带等削减非点源污染的手段,进行总氮输出负荷削减效率的情景模拟,表明10 m植被缓冲带是减少总氮输出负荷的最佳单一控制策略,总氮削减率可达到69.90%;实施综合管理措施对总氮的污染削减效果更佳,10 m植被缓冲带与施肥量减少20%可使总氮削减率达到74.79%。研究结果可为千岛湖水质管理与控制提供理论基础。

河套灌区地表水污染溯源分析

针对河套灌区地表水污染来源不清、贡献不明的问题,本文基于9个监测断面月度水质数据,分析灌区地表水环境特征,引用正定矩阵因子分析模型解析污染来源及其空间差异性.结果表明:(1)有机污染指标(COD_(Mn)、COD、BOD_(5))和总氮是河套灌区的主要超标因子,总氮指标低于GB 3838-2002《地表水环境质量标准》Ⅲ类标准的样品数量占比超过67%,整体来说支排干水质差于总排干.其中,七排干入总排干口污染最重,COD_(Mn)与总磷浓度分别超GB 3838-2002Ⅲ类水质标准限值的109%和160%;其次是五排干入总排干口和三排干入总排干口.(2)散养畜禽粪污和秸秆还田以及生产生活污水输入分别是河套灌区地表水有机污染和氮的主要来源,贡献率分别达56.22%和47.82%.(3)河套灌区地表水污染来源具有明显的空间异质性,种植业磷肥输入是影响二排干、三排干和总排干上游水质的主要因素,生产和生活污水输入是影响五排干、七排干和总排干下游水质的主要因素.本文依托监测断面常规监测指标结合数学模型方法,实现了对河套灌区沟渠系统地表水污染的定量溯源,并分析了各监控断面的主要污染风险.