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1.
通过调查和收集阜阳市颍河流域2007-2011年的社会、经济、人口、环境资料和数据,运用PSR模型分析颍河流域阜阳段内的主要污染源,采用环境综合评价指数法确定农业面源污染为研究区域主要污染源,工业污染和城市生活污染源次之;通过对压力、状态、响应和环境综合评价指数进行了分析。结果表明:2007-2011年研究区域内重点实施工业污染源治理和污染减排示范工程对颍河流域阜阳段内水环境改善有一定的成效。  相似文献   

2.
Communities throughout the United States are developing and implementing watershed management plans to address nonpoint sources of pollution and meet Total Maximum Daily Load (TMDL) requirements. Once a TMDL is established, a watershed management plan is developed and implemented to reduce contaminant sources and attain TMDL goals. Developing an effective TMDL and remediation plan should take into account fluctuation of pollution loadings and the timing of first-flush events. The objective of this study is to investigate the effect of hydrological conditions on microbial pollutant levels at a TMDL site during spring and summer storm events. A total of 64 water samples were collected from Sloan Creek in mid-Michigan in the spring/summer of 2015. All samples were analyzed to quantify concentrations of E. coli, bovine-associated Bacteroides (BoBac) gene markers, and human-associated Bacteroides (HuBac) gene markers. Discharge was the driving force of microbial contaminant loading in the studied water body. E. coli concentrations had significant strong correlation with precipitation and discharge, and BoBac concentrations were positively related to discharge. E. coli, BoBac and HuBac patterns suggested first-flush phenomena occurred during summer storms. E. coli permit exceedance rates increased from 31% before first-flush, to 100% during and after first-flush in the summer. The resulting information may help develop a plan for restoring impaired waters and establish the maximum amount of pollutants that the body of water can receive during different hydrological conditions.  相似文献   

3.
Animal feeding operations are being targeted as sources of point and nonpoint pollutants. In response to the need to improve water quality, governments and agencies are enacting new regulations proscribing activities to reduce pollutants entering waters. Pursuant to the Clean Water Act, the United States federal government regulates concentrated animal feeding operations (CAFOs) as point sources of pollution. In 2001, the U.S. Environmental Protection Agency advanced more stringent regulations for CAFOs despite the fact that approximately80% of the CAFOs have not secured permits as required by federal law. An analysis of enforcement mechanisms and opportunities for greater enforcement suggests that reductions in pollution could come from more effective enforcement. Rather than adopting more regulations for animal feeding operations, governments might direct their resources towards detecting and enforcing existing provisions.  相似文献   

4.
The extreme southern portion of Green Bay is a shallow (1 to 5 m depth), eutrophic water body which receives considerable nutrients from the Fox River and metropolitan Green Bay, Wisconsin. Research to evaluate the effect of sediments on nitrogen (N) in the bay entailed periodic sampling of waters and sediments at six sites over 20 months and laboratory investigations of the rates of nitrification, denitrification, mineralization, immobilization, and N2 fixation. The monitoring data indicated that the N concentrations, approximately 0.6 and 0.8 mg/L of inorganic and organic N, respectively, in the bay waters are considerably higher than the threshold limits that may cause algal bloom and aquatic weed problems. Consideration of the available sediment N pool with respect to recognizable N inputs indicated that only 1.2 percent of the yearly N loading from the Fox River is present in the active sediment layer. Nitrification and subsequent denitrification at the sediment-water interface as a result of intermittent wind stirring could be a major sink for N, but presently it has a minor impact due to the high loading rate of N in this ecosystem. The study indicates that even if approximately 50 percent of the present point source loading of N were eliminated by pollution abatement, the N input from nonpoint sources (combined with existing concentrations of phosphorus in the bay waters) would be sufficient to maintain eutrophic conditions.  相似文献   

5.
The water quality of seafronts and beaches of Mumbai is under pressure and deteriorating due to discharge of partially treated sewage and wastewater through point and nonpoint sources. The objective of the study was to assess the water quality and to correlate physico-chemical and bacteriological parameters for establishing relationship, association and dependence on each other. The water quality parameters were selected as per SW II standards specified by Central Pollution Control Board, India and nutrient parameters as strong indicators of sewage pollution. Box and whisker plots were generated for evaluating spatio temporal variation of water quality which suggest influence of organic pollution mostly at Mahim and Dadar in the form of outliers and extremes. Pearson's correlations were estimated between parameters and found significant correlation with each other indicating influence of sewage on water quality. The water quality of beaches and seafronts were found unsafe for recreational purposes. The study suggested that designated water quality can be achieved by restricting nonpoint source through improvement in wastewater collection systems, appropriate level of treatment and proper disposal.  相似文献   

6.
Pollutant load reductions are often required to restore aquatic ecosystems experiencing eutrophication. Loads can be estimated using watershed models or data from monitoring stations, however data availability can limit the timeliness or comprehensiveness of the load estimates. We developed an approach to address this challenge that used watershed model results to estimate the proportion of annual nonpoint source nitrogen (N), phosphorus (P) and sediment (Sed) loads derived from unmonitored catchments. This proportion was multiplied by the nonpoint portion of United States Geological Survey (USGS) estimated annual river loads to account for annual variation in hydrologic conditions. Total loads were calculated as the sum of measured river loads, reported point sources from unmonitored areas and the estimated nonpoint source loads from unmonitored catchments. We applied this approach to the Chesapeake Bay because of its socio‐economic and ecological importance. Median watershed loads for N, P and Sed were 140, 6.4 and 3030 Mg year?1, respectively (1990–2004). Nonpoint source loads from the monitored areas constituted the greatest source of N, P and Sed (55, 47 and 74% respectively) to the Bay. The high N, P and Sed yield rates (7.3, 0.38 and 99 kg ha?1 year?1, respectively) from nonpoint loads originating from unmonitored areas near the Bay resulted in 25, 32 and 26% (N, P and Sed, respectively) of the Bay's total loads (excluding direct atmospheric deposition, shoreline erosion and oceanic inputs). Disproportionately high loads of P and Seds were associated with years that experienced elevated discharge whereas N loads were directly related to discharge. Error estimates indicated that our methods were most reliable for N (±6%) but reasonable for P (±22%) and provide an effective technique for the timely estimation of pollutant loads from watersheds with unmonitored catchments. Management strategies that decrease N deposition and reduce runoff to control P and Sed transport will effectively reduce pollutant loads. Published in 2010 by John Wiley & Sons, Ltd.  相似文献   

7.
Main pollution sources in multipurpose dam watersheds in Korea are highland fields, stream banks, livestock farms, roads, and construction sites. Specifically, highland fields are the major nonpoint pollution sources. Excessive organic chemicals such as fertilizer and pesticide can be exuded from the land, and the area is likely to be eroded by heavy rain. Fallow, conservative cultivation, and covering can be alternatives for soil protection and reinforcement. In addition to these, construction of detour waterways and improvement of irrigation method can minimize the impact of runoff. In the case of slope in 15% degree or more, prohibiting cultivation and restoring the surface is preferred to improving cultivation method in order to control nonpoint pollution sources efficiently.  相似文献   

8.
Jin-feng Xue  Jun Xia 《国际水》2013,38(3):428-438
Abstract

In light of the current ability to treat point source pollution, nonpoint source (NPS) pollution has become the primary cause of water pollution. In order to manage and control NPS pollution, we must conduct research on NPS pollution. An effective means for such an endeavor is to construct a mathematical model. However, in the present continuous time and distributed parameter NPS models, such as SWAT, parameter requirements are so numerous that their application is very difficult. In order to make such a model convenient for application, research was first conducted before constructing a new continuous time and distributed parameter NPS pollution model based on hydrodynamics. In this paper, as one of its sub-models, the runoff sub-model is introduced. This sub-model is composed of the SCS model and the water routing model that was constructed by the authors of this paper. This water routing model is based on Saint-Venant equations. Through Laplace transform and inverse Laplace transform mathematical modeling, the outflow hydrograph that is an S-curve was obtained. Then, the authors built the relation between S-curve and water- collecting area coefficient, from which the water routing model is derived. In order to calibrate and validate the new model, the authors applied it in the Guishuihe watershed with satisfactory results. The results show that it has value in application, especially in the area where data are scarce.  相似文献   

9.
基于江苏省2007年、2009—2011年4次污染源普查资料,选取COD和NH3-N为研究因子,统计江苏省太湖流域2007年、2009—2011年污染物排放变化规律;根据已核定的区域纳污能力以及总量控制值,对研究区域入河量及排放量进行削减分析(以2010年为现状年)。结果表明:12007年、2009—2011年江苏省太湖流域污染物排放总量逐年下降,其中城镇点源所占比例呈逐年下降趋势,面源比例呈增长趋势;2"十二五"期间,江苏省太湖流域COD和NH3-N的入河量削减率分别为20%和65%;3"十二五"期间,江苏省太湖流域COD和NH3-N的点源排放削减率分别为27%和35%。  相似文献   

10.
Malin Falkenmark 《国际水》2013,38(2):136-146
Abstract

Humans and many of their activities depend on clean water but pollute it during use. Water—a unique solvent—when moving through the landscape on its way to the river mouth, meets pollutants almost “everywhere” along its pathways. As a result, water pollution has been building up over time in rivers, lakes, aquifers and coastal waters. The pollution situation is particularly serious in industrializing, developing countries, where polluting, medium-scale industry constitutes the socio-economic backbone of whole cities and regions, which seriously complicates implementation of strict and costly pollutant abatement regulations. Evidence is now increasing of water pollution threatening the economic development of megacities, small islands, and shared transnational river basins. A set of global scenarios suggest that the world may be facing severe health effects from persistent pollutants some four decades from now. Difficulties in reversing the escalating water pollution have been severely underestimated both in terms of the possibility to finance, the social acceptance of abatement efforts, the time delays involved in achieving intended result, and the administrative fragmentation thresholds. The article explains the dilemma and the shifts in thinking needed to reverse the dangerous development and concludes that the water community has to take much stronger part in the debate to counteract the current resource illiteracy and to help diverting humanity from the population and economic collapses projected to happen.  相似文献   

11.
Water quality in China shows an overall trend of deterioration in recent years. Nonpoint source pollution from agricultural and rural regions is the leading source of water pollution. The agricultural nonpoint source pollutants are mainly from fertilization of cropland, excessive livestock and poultry breeding and undefined disposal of daily living wastes in rural areas. Agricultural nonpoint sources contribute the main source of pollution to most watersheds in China, but they are ignored in management strategy and policy. Due to the lack of full understanding of water pollution control and management and the lack of perfect water quality standard systems and practical legislative regulations, agricultural nonpoint source pollution will become one of the biggest challenges to the sustainable development of rural areas and to society as a whole. The system for agricultural nonpoint source pollution control in China should include an appropriate legislation and policy framework, financing mechanisms, monitoring system, and technical guidelines and standards. The management of agricultural nonpoint source pollution requires multidisciplinary approaches that will involve a range of government departments, institutions and the public.  相似文献   

12.
排污口群污染物控制排放量与削减量的计算   总被引:4,自引:0,他引:4  
庞熙 《人民珠江》2006,(3):45-47
0引言水资源保护规划中,对水功能区纳污能力的计算,一般是按单一河道简化处理。对功能区内的多个入河排污口,则将它们概化成一个集中的排污口,并设该排污口位于河段中点处,即该集中点源的实际自净长度为河段的一半长,因此给出功能区的最大允许纳污量计算公式为:m=[CS-C0exp(-kL  相似文献   

13.
Abstract

Excessive demand for water due to a growing population, agricultural, and industrial development, along with climate change and depletion of nonrenewable resources have intensified the need for integrated water resources management and water pollution control. This paper presents different aspects of a master plan for water pollution control and the results of a case study for developing a master plan for water resources pollution control in Isfahan Province in Iran. Different components of the water resources system and pollution sources in the study area were identified and the effects of each of the pollution sources on surface and groundwater resources contamination were investigated. Two Multiple Criterion Decision Making (MCDM) techniques, namely Simple Additive Weighting (SAW) method and Analytical Hierarchy Structure (AHP) were used in order to determine the share of agricultural, industrial, and domestic sectors in polluting the water resources. In the application of MCDM techniques, engineering judgments and the information gathered from brain storming sessions with engineering experts and the agencies' officials have also been incorporated in order to overcome the data deficiency in this region for this type of analysis. Based on this study, several specific major categories of water pollution reduction projects were defined and in each category, several projects were identified. The total cost of implementation of the projects was also estimated and the projects were prioritized based on their potential impact on water pollution control.  相似文献   

14.
Abstract

It is generally accepted that conflicting demands over international rivers will intensify. There is an active debate on whether this will lead to “water wars” or to unprecedented cooperation. Framing the debate in this manner, however, tends to cast the concept of cooperation as all-or-nothing, implying that “cooperation” is an extreme, in direct opposition to “war.” This conceptual construct obscures the many practical levels of cooperation that states can undertake to their mutual advantage. It is important to recognize that it is entirely rational that states will always have a “national agenda” for a river that they share with other states, and that they will cooperate if it serves that national agenda. In practice, there can be a continuum of levels of cooperation, from simple information sharing, to joint ownership and management of infrastructure investments. Furthermore, it may not necessarily be the case that “more” cooperation reaps “more” benefits in all river basins. There are many different types of benefits that can be secured through the cooperative management of international waters, with each individual basin offering different potential cooperative benefits with different associated costs. For each international basin, the optimal mode of cooperation will depend on a mix of factors including hydrologic characteristics, the economics of cooperative investments, numbers and the relationships of riparians, and the costs of parties coming together.  相似文献   

15.
农村饮用水水源地安全保障与水污染防治   总被引:1,自引:0,他引:1  
沙鲁生 《中国水利》2009,(11):26-28
在分析农村水环境现状和主要污染来源的基础上,提出了农村饮用水水源地安全保障要做好水源地布局、划定保护区、确定水源地的限制排污总量、水源地污染综合治理、加强保护区管理等措施.在农村水污染防治方面要通过对点源、面源污染的防治,减少入河污染量,实现“源头-途径-末端”的全过程污染控制.  相似文献   

16.
Government‐operated water quality monitoring programmes and their long‐term datasets are crucial to documenting improvements in water resource condition in response to changes in pollutant regulation. We present trends in the biological assessment of water quality (benthic macroinvertebrates) and water chemistry, to determine how these indicators of water quality have responded to shifts in pollutants and regulation in streams and rivers of NY between 1972 and 2012. Change in the results of NYS's multimetric index of biological integrity, the Biological Assessment Profile (BAP) score, was compared between four, 10‐year periods at 30 large river and 138 wadeable stream sites. Water Chemistry trends were analysed through calculation of Weighted Regression on Time, Discharge, and Season from 11 long‐term, large river locations from across NYS. Overall, results suggest small, incremental improvements in biological indicators and a shift from point source dominated pollution to nonpoint sources. From 1972 to 2012, 33% of large river sites sampled improved and 13% declined in biological assessment of water quality, 58% of wadeable stream sites sampled showed no change. Macroinvertebrate community models suggest that impact sources are now dominated by nonpoint nutrient sources. Trends in water chemistry concentrations suggest that ammonia, chloride, total Kjeldahl nitrogen, and total phosphorus had the strongest correlations with time. Total phosphorus and total Kjeldahl nitrogen decreased at base flow and increased during high flows, whereas ammonia decreased across a range of discharges, indicating the shift to nonpoint sources of nutrients and supporting the trends observed in biological indicators.  相似文献   

17.
Abstract

This paper reviews the processes by which groundwater and surface water flows are polluted by nitrates on the Island of Jersey in the English Channel. It is shown that the primary cause of such pollution is the use of nitrate fertilizers by the Island's farmers. The activities of the major government institutions involved in reducing nitrate pollution are described and the costs of such management are assessed. The instruments deployed are regulatory, infrastructural, and educational; in contrast, economic instruments have not been deployed. The article then moves on to consider the benefits of pollution reduction in respect of enhanced environmental quality and improved human health. In conclusion, it is suggested that the standard for the nitrate content of drinking water, based on European Community legislation of 1980, was set at a level for which no human health benefits have been demonstrated but at substantial costs to the citizens of Jersey. This “cost without benefit” hypothesis is applicable to many other countries with respect to nitrate pollution management.  相似文献   

18.
基于对浊漳河水系三典型支流2008年逐月进行水质监测分析,通过时空变异两个角度对这3条支流的水质进行了对比研究.结果表明:①以农业非点源污染为主的河谷平川河流水质最好;以农业非点源污染为主的高山峡谷河流,由于受到农业活动的影响,水质相对较差;受工业废水和城市生活污水污染的支流河流水质最差,有机物和氮磷指标严重超标.②3条支流中4个化学指标(NH4+-N、TN、TP、CODMn)在不同水域、不同季节具有明显差异.以农业非点源污染为主的河流氮营养盐浓度在丰水期较高,在枯水期较低,TP浓度和CODMn浓度在各个雨期之间变化不大,且相对稳定;以点源污染严重的河流氮营养盐浓度在枯水期最高,在丰水期最低,个别断面TP和CODMn污染表现突出.  相似文献   

19.
Water quality impairment of Great Lakes beaches is caused by fecal pollution from point and nonpoint sources. Erosion due to wind or wave action, invasive vegetation and chronically wet, flooded or standing water are conditions that can magnify water quality problems at beaches. We investigated the hydrological and geophysical characteristics of the Bradford Beach on Lake Michigan (Milwaukee, WI) and the linkage between standing water and persistent contamination by fecal indicator bacteria (FIB). Our study showed that there is a positive correlation between high concentrations of Escherichia coli (E. coli) in sand and high moisture content caused by standing water. The main factor associated with the formation of standing water was rainfall. There were also notable differences in standing water and/or wet sand conditions in the northern and southern parts of the beach. These differences could be accounted for by differences in ground water elevations and beach erosion and accretion patterns. Other important physical features of the beach were the presence of rain gardens and mean grain diameter (d50). Rain gardens above the beach face that capture runoff contributed to transient increases in the water table, facilitating standing water formation. Standing water, stormwater runoff infiltrating through the sand and into groundwater as well as wave run up that delivered contaminated surface water to the back beach area were of health concern following heavy rainfall events. The outcomes of this study will likely be useful to beach managers investigating mechanisms/sources of fecal indicator bacteria loading and potential mitigative approaches.  相似文献   

20.
Abstract

This article constructs a cost calculator to estimate the economic competitiveness of solar-powered desalination in Saudi Arabia. Solar desalination is defined as a plant that obtains solar energy from a closed system. This is done to focus the investigation on desalination technologies, rather than the efficacy of replacing conventional energy sources with renewables in an integrated electricity grid. The results suggest that current options for solar-powered desalination are not cost-competitive compared to incumbent technologies in Saudi Arabia. The article offers insight into where costs must decrease before solar technologies are economically competitive in the country.  相似文献   

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