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1.
This paper describes an online water quality monitoring and management system that was developed by combining a chemical oxygen demand sensor with an artificial neural network technology and a virtual instrument technique. The system was used to model the hydrological environment of the Liming River basin in Daqing City, China, in an effort to maintain the water quality in this basin at a level compatible with the status of Daqing City as a scenic resort. Operation of the system during the past 2 years has shown that an optimal allocation of water (including water released from an environmental reservoir to mitigate pollution events) could be achieved for the basin using the information gathered by the system; using mathematic models established for this system, the quantity of water released from the reservoir is adequate to improve the overall water environment. The results demonstrate that the system provides an effective approach to water quality control for environmental protection.  相似文献   

2.
Effect of reservoir flushing on downstream river water quality   总被引:1,自引:0,他引:1  
The effect of short-term reservoir flushing on downstream water quality in the Geum River, Korea was studied using field experiments and computer simulations. The reservoir release was increased from 30 to 200 m(3)/s within 6 h for the purpose of this experiment. The flushing discharge decreased the concentrations of soluble nitrogen and phosphorus species considerably, but the experimental results revealed a negative impact on organic forms of nutrients and biochemical oxygen demand (BOD). A dynamic river water quality model was applied to simulate the river hydraulics and water quality variations during the event. The model showed very good performance in predicting the travel time of flushing flow and the variations of dissolved forms of nitrogen and phosphorus constituents. However, it revealed a limited capability in simulating organic forms of nutrients and BOD because it does not consider the re-suspension mechanism of these constituents from sediment during the wave front passage.  相似文献   

3.
Good water quality of the Rio San Juan is critical for economic development of northeastern Mexico. However, water quality of the river has rapidly degraded during the last few decades. Societal concerns include indications of contamination problems and increased water diversions for agriculture, residential, and industrial water supplies. Eight sampling sites were selected along the river where water samples were collected monthly for 10 mo (October 1995-July 1996). The concentration of heavy metals and chemical constituents and measurements of bacteriological and physical parameters were determined on water samples. In addition, river discharge was recorded. Constituent concentrations in 18.7% of all samples exceeded at least one water quality standard. In particular, concentrations of fecal and total coliform bacteria, sulfate, detergent, dissolved solids, Al, Ba, Cr, Fe, and Cd, exceeded several water quality standards. Pollution showed spatial and temporal variations and trends. These variations were statistically explained by spatial and temporal changes of constituent inputs and discharge. Samples collected from the site upstream of El Cuchillo reservoir had large constituent concentrations when discharge was small; this reservoir supplies domestic and industrial water to the city of Monterrey.  相似文献   

4.
Ecological perspective on water quality goals   总被引:32,自引:0,他引:32  
The central assumption of nonpoint source pollution control efforts in agricultural watersheds is that traditional erosion control programs are sufficient to insure high quality water resources. We outline the inadequacies of that assumption, especially as they relate to the goal of attaining ecological integrity. The declining biotic integrity of our water resources over the past two decades is not exclusively due to water quality (physical/chemical) degradation. Improvement in many aspects of the quality of our water resources must be approached with a much broader perspective than improvement of physical/chemical conditions. Other deficiencies in nonpoint pollution control programs are discussed and a new approach to the problem is outlined.  相似文献   

5.
河流水污染和水资源短缺是楚雄市面临的两大水环境问题。本文将楚雄市社会经济发展、水污染控制和水资源开发利用纳入一个系统,在掌握水环境问题现状和变化趋势及其成因的基础上,探讨河流水质目标和排污控制目标,从宏观协调对策和水污染控制措施两个层次上进行水环境对策的设计和多目标优选,并得到最佳水污染控制实施计划。  相似文献   

6.
A susceptibility indexing method was developed based on vulnerability and quality indices. The contamination susceptibility index (SI) at a given location was calculated by taking the product of the vulnerability index (VI) and the quality index (QI): SI = VI × QI. This method incorporates both hydrogeological and hydrochemical data for a comprehensive index mapping. The DRASTIC index methodology was used for the hydrogeological data evaluations. The quality index calculation procedure based on a water quality classification scheme was introduced to evaluate hydrochemical data. The suggested susceptibility indexing method was applied to the Küçük Menderes river basin located in western Turkey. The susceptibility index map shows both hydrogeological and hydrochemical data related to the contamination problem including areas that should be taken into consideration during water management planning. The index map indicates that the most susceptible groundwater is located along the river channel between Kiraz and Tire towns, in the Selçuk area and along the Fertek stream channel to the north of Torbal? town. The results indicate that the incorporation of both hydrogeological and hydrochemical datasets enables more realistic evaluations than those of an individual dataset to estimate the groundwater contamination susceptibility of an aquifer. The numerical procedure applied could be extended further by including other parameters such as retardation, potential contaminant sources, etc. that affect the water quality in a given basin.  相似文献   

7.
水资源开发利用与城市水环境建设问题对策初探   总被引:4,自引:0,他引:4  
本文以科学发展观回顾以往水资源利用与城市水环境建设的实践,并以成都市水环境为例,发现包括上游河流水资源过度开发使下游河流生态受破坏;城市内水环境建设过多地填埋与覆盖原有水系河道造成城区缺水与污染隐患;城市上游优质水资源浪费;城市污水处理厂布局不合理,过多的集中在下游排放使纳污河生态环境严重破坏等问题,提出了一些研究项目与对策建议.  相似文献   

8.
以闽江下游福州城区段为研究区间,分析了闽江下游福州段的水环境质量现状,采用二维水动力-水质耦合模型研究了枯水期城市排污口布局和排污强度规划对水环境质量的影响。研究结果表明,感潮河段排污存在明显的污染物上溯现象,在东南区水厂至马尾水厂备用水源地之间形成高浓度污染团,洋里和连坂排污口对东南区水厂水源地水质影响最为显著,高潮时刻的高锰酸盐指数增量将达1.0mg/L,氨氮增量将达约0.15mg/L,叠加本底值后水质已接近Ⅲ类标准限值。建议逐步将取水口向城市上游淮安段转移,更换取消东南区水厂的取水口。  相似文献   

9.
ABSTRACT: The Caloosahatchee River has two major sources of freshwater one from its watershed and the other via an artificial connection to Lake Okeechobee. The contribution of each source to the freshwater discharge reaching the downstream estuary varies and either may dominate. Routine monitoring data were analyzed to determine the effects of total river discharge and source of discharge (river basin, lake) on water quality in the downstream estuary. Parameters examined were: color, total suspended solids, light attenuation, chlorophyll a, and total and dissolved inorganic nitrogen and phosphorus. In general, the concentrations of color, and total and dissolved inorganic nitrogen increased, and total suspended solids decreased, as total discharge increased. When the river basin was the major source, the concentrations of nutrients (excepting ammonia) and color in the estuary were relatively higher than when the lake was the major source. Light attenuation was greater when the river basin dominated freshwater discharge to the estuary. The analysis indicates that water quality in the downstream estuary changes as a function of both total discharge and source of discharge. Relative to discharge from the river basin, releases from Lake Okeechobee do not detectably increase concentrations of nutrients, color, or TSS in the estuary.  相似文献   

10.
通过对2006—2010年昌黎县地表水监测数据进行分析得出:昌黎县水环境质量总体趋于好转,河流出境断面水质化学需氧量呈下降趋势,环境质量好于入境断面,但仍为劣V类。污染产生的主要原因是:昌黎县淀粉、造纸等企业所产生废水的有机物含量较高,部分企业污水处理设施陈旧,废水不能稳定达标排放,且有偷排、偷放、漏排等现象。针对上述问题,从加强项目审批、污染减排、环境综合整治,强化环境执法,加大资金投入等方面提出了对策与建议。  相似文献   

11.
This paper seeks to identify some promising policy options which could be part of a strategic and holistic effort to address India's future water challenges. Significant increases in agricultural water productivity would be a major factor in reducing the need for developing new water sources. Crop diversification, appropriately targeted to account for the present agricultural systems and available water resources, will increase productivity. Furthermore, much more emphasis needs to be placed on effective management of the groundwater resources through renewed efforts to enhance artificial recharge and conservation. Also, efforts should be revived to improve the existing surface irrigation systems. In particular, systems could be reconfigured to provide a more reliable water supply and allow effective community level management, where appropriate. Finally, while some of the increasing demands from domestic and industrial users will be met by the development of groundwater and reallocation of water from the agricultural sector, this will not be sufficient. Given that such conditions are emerging in states with high economic growth and relatively water scarce basins, this will require the further development of water resources. In some cases, these conditions along with the demand for reliable water for high value crops, will be part of the justification for inter‐basin transfers.  相似文献   

12.
The objective of this work is to analyze and interpret the components or hydrogeological, physical, and chemical variables of the San Diego aquifer to describe it and explain its influence on the sustainable use of groundwater for the providing of this locality. The San Diego municipality covers most of the area of the aquifer and is an area of high urban development that currently needs the contribution of groundwater due to the deficit presented by the main supply from the Central Regional System. Said aquifer is a set of geological strata located within the limits of the San Diego River basin, in the state of Carabobo, which are capable of storing groundwater and transmitting it. Data on lithology, porosity, and pumping level were investigated, which allows calculating an estimate of the volume of water available in the aquifer. Regarding the quality of the water, the data on hardness, chlorides, sulfates, nitrates, conductivity, calcium, magnesium, and pH, show that the water towards the center and north of the aquifer is of good quality, being able to classify it as type 1A, while toward the southern end—this is of lower quality, where the mineral parameters are higher, which is related to the probable intrusion of brackish water from Lake Valencia. It is concluded by establishing that the volume of groundwater, its availability, extraction feasibility, and its quality, make it suitable for urban supply and that said extraction is sustainable. But a better-integrated type of management must be designed, considering the contribution of the Regional System of the Center and the adequacy of the distribution networks.  相似文献   

13.
Annual precipitation and river water volumes and chemistry were measured from 1995 to 1998 in a mesoscale agricultural area of southeast Brazil. Precipitation was mildly acidic and solute concentrations were higher in the west than in the east of the basin. Combustion products from biomass burning, automobile exhaust, and industry typically accumulate in the atmosphere from March until October and are responsible for seasonal differences observed in precipitation chemistry. In river waters, the volume-weighted mean (VWM) concentrations of major solutes at 10 sites across the basin were generally lower at upriver than at downriver sampling sites for most solutes. Mass balances for major solutes indicate that, as a regional entity, the Piracicaba River basin was a net sink of H+, PO4(3-), and NH4+, and a net source of other solutes. The main stem of the Piracicaba River had a general increase in solute concentrations from upriver to downriver sampling sites. In contrast, NO3- and NH4+ concentrations increased in the mid-reach sampling sites and decreased due to immobilization or utilization in the mid-reach reservoir, and there was denitrification immediately downriver of this reservoir. Compared with tributaries of the Chesapeake Bay estuary, the Piracicaba River is affected more by point-source inputs of raw sewage and industrial wastes than nonpoint agricultural runoff high in N and P. Inputs of N and C are responsible for a degradation of water quality at downriver sampling sites of the Piracicaba River drainage, and water quality could be considerably improved by augmenting sewage treatment.  相似文献   

14.
尼洋河流域水资源十分丰富,水能蕴藏量巨大,生态环境良好。随着西藏经济的发展,必将出现大规模开发利用水资源的趋势,探讨流域水资源和环境的现状及可持续发展具有十分重要的现实意义。本文对尼洋河流域基础资料的收集与整理,分析尼洋河流域的特点与现存的问题,根据收集的水质监测资料,分析了流域污染源概况和构成,以未进行水环境功能区划为前提,选择模糊综合评价法对尼洋河流域水环境质量进行现状评价,并对超标断面进行了原因分析,通过对2012年尼洋河流域14个监测断面监测成果的评价,得出尼洋河流域水质现状良好的结论,为以后的水功能区划分、水质目标的确定以及水环境功能区划分提供依据。  相似文献   

15.
ABSTRACT: Tidally influenced reaches of several coastal rivers in eastern North Carolina are suffering from very serious water quality problems — massive surface blooms of noxious blue-green algae, major fish kills from anoxic water, epidemics of red sore disease among fish, fresh water intrusion into estuarine waters, and declining commercial and sports fisheries. An intensive investigation of point source and nonpoint source inputs of nutrients was conducted in one of the eutrophic rivers, the Chowan River. Nonpoint source loading dominated the estimated annual flu of nutrients from the river basin. Automated water quality samplers were utilized to record nutrient levels in stormflow and baseflow from several small agricultural watershed in the basin. Levels of nitrate nitrogen and total phosphorus were from five to 40 times greater in these agricultural watersheds than levels in mostly forested watersheds. Existing water quality data in these eutrophic river basins implicate agricultural activities – particularly animal operations and cropland in watersheds with extensive drainage improvements – as the major contributing factor to the water quality problems.  相似文献   

16.
The Water Framework Directive is a major regulatory reform of water resources management within the European Union. Integrated catchment management plans must be prepared for all river basins, in order to achieve 'good ecological status' in all EU waters. Ecological status is a broader measure of water quality than the chemical and biological measures that were previously dominant. The Directive calls for a consideration of the economic costs and benefits of improvements to ecological status. In this paper, we use the choice experiment method to estimate the value of improvements in three components of ecological status. Given the high resource cost of valuation studies, benefits transfer methods will be needed in implementing the Directive. We thus also test the ability of choice experiments for benefits transfer across two very similar rivers in the UK.  相似文献   

17.
The term “body of groundwater” represents a new administrative tool established by the water framework directive (WFD) in order to manage European groundwaters. Its practical application raises some difficulties due to unclear definitions and the large heterogeneity of European aquifers. In this work, a methodology is proposed to carry out the delineation of bodies of groundwater according to the requirements of the WFD. This methodology faces up to some of the major difficulties that can arise during the delineation, such as the identification of bodies of groundwater in multilayered aquifers, boundaries between superposed groundwater bodies, and delimitation in low permeability materials or in dismembered aquifers. In order to show its practical application, the proposed methodology is applied in a pilot Mediterranean river basin located in southern Spain. Results show that previous knowledge of the hydrogeological conditions is necessary to enable a correct delineation of groundwater bodies. Finally, alternative procedures are proposed for low permeability and small aquifers in order to reduce the number of groundwater bodies identified and simplify their overall management.  相似文献   

18.
Environmental decision support systems (EDSSs) are an emerging tool used to integrate the evaluation of highly complex and interrelated physicochemical, biological, hydrological, social, and economic aspects of environmental problems. An EDSS approach is developed to address hot-spot concerns for a water quality trading program intended to implement the total maximum daily load (TMDL) for phosphorus in the Non-Tidal Passaic River Basin of New Jersey. Twenty-two wastewater treatment plants (WWTPs) spread throughout the watershed are considered the major sources of phosphorus loading to the river system. Periodic surface water diversions to a major reservoir from the confluence of two key tributaries alter the natural hydrology of the watershed and must be considered in the development of a trading framework that ensures protection of water quality. An EDSS is applied that enables the selection of a water quality trading framework that protects the watershed from phosphorus-induced hot spots. The EDSS employs Simon’s (1960) three stages of the decision-making process: intelligence, design, and choice. The identification of two potential hot spots and three diversion scenarios enables the delineation of three management areas for buying and selling of phosphorus credits among WWTPs. The result shows that the most conservative option entails consideration of two possible diversion scenarios, and trading between management areas is restricted accordingly. The method described here is believed to be the first application of an EDSS to a water quality trading program that explicitly accounts for surface water diversions.  相似文献   

19.
为摸清广安市城市集中式饮用水水源地一、二级保护区周边土壤环境状况,采用单项污染指数评价法和内梅罗综合污染指数法,对广安市河流型、水库型两种典型饮用水水源地保护区土壤污染状况进行评估,并简要分析周边环境敏感点。结果表明:水库型水源地29个、河流型水源地44个土壤检测样品均未检出镉,铜、锌、铅、镍、总铬、汞、砷均检出,变异系数分别在16.6%~62.1%和15.3%~56.6%之间,说明水源地周边土壤环境受到外界的干扰显著;水库型、河流型水源地土壤中铜、锌、铅、镍、总铬、汞、砷污染指数均小于1,表明两处水源地均未受到已检重金属污染;水库型、河流型水源地内梅罗综合污染指数范围分别为0.16~0.68、0.14~0.44,全部点位内梅罗综合污指数评价等级均为Ⅰ级,表明这两处的饮用水水源地周边土壤是清洁安全的。  相似文献   

20.
祝新明  袁婧  王翡  李莉  吕升 《四川环境》2022,(1):169-174
以2015 ~2019年长山河4个水质监测站的监测数据为基础,采用综合水质标识指数法对其历年水质进行评价,利用季节性kendall检验法对各监测断面的高锰酸盐指数,氨氮,总磷等3个监测指标变化趋势进行分析.结果 表明:长山河各断面的综合水质均达到或优于水功能区目标要求,水质污染总体呈下降趋势,其中长山河大桥和长山闸一号...  相似文献   

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