Effect and Control of Pollution in Catchment Area of Lake Sapanca, Turkey

/ Land-based point and diffuse pollution sources in the catchment area of Lake Sapanca, Turkey, were investigated. The present and future distribution of pollution loads were evaluated in terms of nitrogen, phosphorus, biochemical oxygen demand, and pesticides. A methodology for the estimation of pollution loads was presented; most of which were based on "unit loads." Presently domestic and industrial point sources dominate over diffuse sources including fertilizers and pesticides from agricultural use, nutrient loads from forests and meadows, urban runoff, and leachates from unregulated dumps of solid wastes. For the future, the aim of the control action is to maintain the sustainability of the water quality of the lake, at least at the second class of European Community standards. Within this framework; urgent/short-term and medium/long-term control actions will be exercised. In the urgent/short-term stage, simpler and natural ways of treatment will be employed. In the medium/long-term stage an integrated collection and treatment system will be put on operation. After completion of a proposed collection system and treatment plants to handle point sources, the control of diffuse sources will be more significant. Control of diffuse sources for the abatement of further deterioration of water quality then becomes the key issue to be emphasized in the Lake Sapanca catchment area. Diffuse sources control will be achieved by dividing the catchment area into three major protection zones. Use of pesticides and fertilizers on agricultural land and all other activities within these protection zones will be accomplished according to control plans, which will be supervised by an institution established to be responsible of all the activities within the basin.KEY WORDS: Diffuse sources; Land-based pollution; Nutrients; Pesticides; Point sources; Protection zones     

Application of a Multi-Objective Optimization Method to Provide Least Cost Alternatives for NPS Pollution Control

Nonpoint source (NPS) pollutants such as phosphorus, nitrogen, sediment, and pesticides are the foremost sources of water contamination in many of the water bodies in the Midwestern agricultural watersheds. This problem is expected to increase in the future with the increasing demand to provide corn as grain or stover for biofuel production. Best management practices (BMPs) have been proven to effectively reduce the NPS pollutant loads from agricultural areas. However, in a watershed with multiple farms and multiple BMPs feasible for implementation, it becomes a daunting task to choose a right combination of BMPs that provide maximum pollution reduction for least implementation costs. Multi-objective algorithms capable of searching from a large number of solutions are required to meet the given watershed management objectives. Genetic algorithms have been the most popular optimization algorithms for the BMP selection and placement. However, previous BMP optimization models did not study pesticide which is very commonly used in corn areas. Also, with corn stover being projected as a viable alternative for biofuel production there might be unintended consequences of the reduced residue in the corn fields on water quality. Therefore, there is a need to study the impact of different levels of residue management in combination with other BMPs at a watershed scale. In this research the following BMPs were selected for placement in the watershed: (a) residue management, (b) filter strips, (c) parallel terraces, (d) contour farming, and (e) tillage. We present a novel method of combing different NPS pollutants into a single objective function, which, along with the net costs, were used as the two objective functions during optimization. In this study we used BMP tool, a database that contains the pollution reduction and cost information of different BMPs under consideration which provides pollutant loads during optimization. The BMP optimization was performed using a NSGA-II based search method. The model was tested for the selection and placement of BMPs in Wildcat Creek Watershed, a corn dominated watershed located in northcentral Indiana, to reduce nitrogen, phosphorus, sediment, and pesticide losses from the watershed. The Pareto optimal fronts (plotted as spider plots) generated between the optimized objective functions can be used to make management decisions to achieve desired water quality goals with minimum BMP implementation and maintenance cost for the watershed. Also these solutions were geographically mapped to show the locations where various BMPs should be implemented. The solutions with larger pollution reduction consisted of buffer filter strips that lead to larger pollution reduction with greater costs compared to other alternatives.     

四川大学江安校区景观水体水质特征分析

本文以四川大学江安校区景观水体为研究对象,通过近一年,共6次的水质监测采样,研究氨氮、总磷、溶解氧、高锰酸盐指数等水质指标的时空分布特征及变化规律并进行单因子评价。分析了水体富营养化和湖中鱼类的死亡原因并讨论了餐厅排污的影响。研究结果表明:总磷、氨氮和溶解氧是主要污染指标,可导致"水华"、死鱼等问题。最后,提出了相应的治理对策与措施建议。     

Precise and Economical Dredging Model of Sediments and Its Field Application: Case Study of a River Heavily Polluted by Organic Matter,Nitrogen, and Phosphorus

Environmental dredging is an efficient means to counteract the eutrophication of water bodies caused by endogenous release of nitrogen and/or phosphorus from polluted sediments. The huge operational cost and subsequent disposal cost of the dredged polluted sediments, as well as the adverse effect on the benthic environment caused by excessive dredging, make the currently adopted dredging methods unfavorable. Precise dredging, i.e., determining the dredging depth based on the pollution level, not only significantly decreases the costs but also leaves a uniform favorable environment for benthos. However, there is still no feasible process to make this promising method executable. Taking a river heavily polluted by organic compounds as an example, we proposed an executable precise dredging process, including sediment survey, model establishment, data interpolation, and calculation of dredging amount. Compared with the traditional dredging method, the precise one would save 16 to 45 % of cost according to different pollutant removal demands. This precise dredging method was adopted by the National Water Project of China to treat the endogenous pollution of Nanfei River in 2010. This research provides a universal scientific and engineering basis for sediment dredging projects.     

TARGETING NONPOINT SOURCE POLLUTION CONTROL: PHOSPHORUS IN THE MINNESOTA RIVER BASIN1

ABSTRACT: The state of Minnesota seeks to reduce phosphorus loading to the Minnesota River by 40 percent from current levels. Looking at one major watershed in the river basin, we examined the cost effectiveness of targeting versus not targeting specific practices or regions within a watershed for controlling nonpoint phosphorus pollution from agriculture. Integrating biophysical simulation results from current and alternative farming systems with production cost and return estimates enabled us to analyze this policy. Our results indicated it is more cost effective to reduce nonpoint pollution by targeting particular regions or practices in a watershed compared to not targeting. Specifically, producers farming on cropland susceptible to erosion in close proximity to water will appreciably reduce phosphorus nonpoint pollution loading potential by switching from conventional tillage to conservation tillage and by reducing phosphorus fertilization levels to those recommended by the state extension service. Efforts to target those producers in the Minnesota River Basin could reduce potential transaction costs and compensation from “takings” by approximately $50 million (74 percent) over not targeting.     

Riparian buffer strips as a multifunctional management tool in agricultural landscapes: introduction

Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented "edge of field" mitigation measure assumed to provide an effective physical barrier against nitrogen (N), phosphorus (P), and sediment transfer. To ease the legislative process, these buffers are often narrow mandatory strips along streams and rivers, across different riparian soil water conditions, between bordering land uses of differing pollution burdens, and without prescribed buffer management. It would be easy to criticize such regulation for not providing the opportunity for riparian ecosystems to maximize their provision for a wider range of ecosystem goods and services. The scientific basis for judging the best course of action in designing and placing buffers to enhance their multifunctionality has slowly increased over the last five years. This collection of papers aims to add to this body of knowledge by giving examples of studies related to riparian buffer management and assessment throughout Europe. This introductory paper summarizes discussion sessions and 13 selected papers from a workshop held in Ballater, UK, highlighting research on riparian buffers brought together under the EU COST Action 869 knowledge exchange program. The themes addressed are (i) evidence of catchment- to national-scale effectiveness, (ii) ecological functioning linking terrestrial and aquatic habitats, (iii) modeling tools for assessment of effectiveness and costs, and (iv) process understanding enabling management and manipulation to enhance pollutant retention in buffers. The combined understanding led us to consider four principle key questions to challenge buffer strip research and policy.     

人工湿地控制非点源污染的应用

随着点源污染的有效管理和控制，非点源污染已成为水环境污染的主要原因。人工湿地作为一种控制水环境非点源污染的有效工具，已被世界上很多国家所认可。本文首先简述了非点源污染的危害，其次对人工湿地的概念和类型进行了介绍，论述了人工湿地对非点源污染中氮、磷、重金属和农药等主要污染物的去除机理，最后对人工湿地处理系统的附属设施、水力因素、表土层以及植物收割等应用问题进行了探讨。     

The influence of metal source uncertainty on cost-effective allocation of mine water pollution abatement in catchments

In mine water pollution abatement, it is commonly assumed that known mine waste sites are the major pollution sources, thus neglecting the possibility of significant contribution from other old and diffuse sources within a catchment. We investigate the influence of different types of pollution source uncertainty on cost-effective allocation of abatement measures for mine water pollution. A catchment-scale cost-minimization model is developed and applied to the catchment of the river Dalälven, Sweden, in order to exemplify important effects of such source uncertainty. Results indicate that, if the pollution distribution between point and diffuse sources is partly unknown, downstream abatement measures, such as constructed wetlands, at given compliance boundaries are often cost-effective. If downstream abatement measures are not practically feasible, the pollution source distribution between point and diffuse mine water sources is critical for cost-effective solutions to abatement measure allocation in catchments. In contrast, cost-effective solutions are relatively insensitive to uncertainty in total pollutant discharge from mine water sources.     

基于十圩港考核断面达标的入江支流污染来源研究

泰州靖江市新十圩港大桥省考断面近年来水质出现超标现象,为了控制该断面水质达标,不让超标水汇入长江.基于水文、水质和污染源资料,建立了靖江市十圩港河流一维水环境数学模型.利用控制断面达标法、污染影响分担率计算法得到十圩港河道的水环境容量与各镇分担率.与现状污染物入河量对比,从而确定了研究区域内各类污染物的削减量;根据各入...     

Water Quality Trading with Lumpy Investments,Credit Stacking,and Ancillary Benefits

This paper studies the economics of a water quality trading market in a predominantly agricultural watershed, and explores the effects of credit stacking in such a market when buyers and sellers of pollution credits can only reduce pollution with large, discrete investments that yield discontinuous supply and demand. The research simulates hypothetical water quality trading markets in the corn‐belt area of Illinois, where wastewater treatment plants (WWTPs) can pay farmers to reduce nutrients by installing wetlands and farmers may or may not be allowed to earn payments for multiple services from one wetland. We find that wetlands are a more cost‐effective way to mitigate nitrogen pollution than abatement by WWTPs. Stacking credits may improve social welfare while providing more ecosystem services if there is enough demand for the primary credit in the market (nitrogen) to cover most of the cost of installing the wetland but the supply of nitrogen credits is not exhausted. However, in the presence of lumpy pollution reduction activities, the effects of allowing stacked credit sales are idiosyncratic and not necessarily positive; stacked payments may or may not satisfy additionality. The results imply that credit trading for nitrogen is likely to make society better off, but the effects of allowing farmers to receive multiple payments from a single wetland depend on details of the situation.     

GENERALIZED WATERSHED LOADING FUNCTIONS FOR STREAM FLOW NUTRIENTS1

ABSTRACT: Loading functions are proposed as a general model for estimating monthly nitrogen and phosphorus fluxes in stream flow. The functions have a simple mathematical structure, describe a wide range of rural and urban nonpoint sources, and couple surface runoff and ground water discharge. Rural runoff loads are computed from daily runoff and erosion and monthly sediment yield calculations. Urban runoff loads are based on daily nutrient accumulation rates and exponential wash off functions. Ground water discharge is determined by lumped parameter unsaturated and saturated zone soil moisture balances. Default values for model chemical parameters were estimated from literature values. Validation studies over a three-year period for an 850 km² watershed showed that the loading functions explained at least 90 percent of the observed monthly variation in dissolved and total nitrogen and phosphorus fluxes in stream flow. Errors in model predictions of mean monthly fluxes were: dissolved phosphorus - 4 percent; total phosphorus - 2 percent; dissolved nitrogen - 18 percent; and total nitrogen - 28 percent. These results were obtained without model calibration.     

EFFECTS OF SLUDGE AND CHEMICAL FERTILIZER APPLICATION ON RUNOFF WATER QUALITY1

ABSTRACT: Simulated rainfall was used on experimental field plots to compare the effect of chemical fertilizer and sludge application on sediment, nitrogen, and phosphorus in runoff from no-till and conventional tillage systems. Chemical fertilizer application under the no-till system resulted in the least amount of total N and P in surface runoff. However, sludge application under the no-till system resulted in the least amount of NO₃-N and sediment in surface runoff. The worst water quality scenarios were observed when either sludge or chemical fertilizer were surface-applied under a conventional tillage system. Nitrogen losses from the conventional tillage system were minimized when sludge was incorporated into the soil. However, phosphorus and sediment yield from such a system were significantly higher when compared to phosphorus and sediment yield from the no-till system. The results from this study indicate that the use of sludge on agricultural land under a no-till system can be a viable alternative to chemical fertilizer for nitrogen and phosphorus control in runoff. A more cautious approach is recommended when the sludge is incorporated into the soil in a conventional tillage system because of potential for high sediment and phosphorus yield in surface runoff.     

篦齿眼子菜对废水中氮和磷的去除行为研究

一些常见的沉水草本植物对水质具有较强的净化作用,能够有效控制氮和磷的浓度.本试验通过模拟氮、磷污染的水质条件,采用篦齿眼子菜对氮、磷营养盐的吸附和去除效果进行研究.结果 表明:设定模拟废水中的初始总氮(TN)浓度在1～50 mg/L范围内,培养30天后的植株对总氮的去除率最高可达85.4％,随着初始培养环境中总氮浓度的...     

Agricultural Land Use and Best Management Practices to Control Nonpoint Water Pollution

In recent years, improvements in point-source depuration technologies have highlighted the problems regarding agricultural nonpoint (diffuse) sources, and this issue has become highly relevant from the environmental point of view. The considerable extension of the areas responsible for this kind of pollution, together with the scarcity of funds available to local managers, make minimizing the impacts of nonpoint sources on a whole basin a virtually impossible task. This article presents the results of a study intended to pinpoint those agricultural areas, within a basin, that contribute most to water pollution, so that operations aimed at preventing and/or reducing this kind of pollution can be focused on them. With this aim, an innovative approach is presented that integrates a field-scale management model, a simple regression model, and a geographic information system (GIS). The Lake Vico basin, where recent studies highlighted a considerable increase in the trophic state, mainly caused by phosphorus (P) compounds deriving principally from the intensive cultivation of hazelnut trees in the lake basin, was chosen as the study site. Using the management model Groundwater Loading Effects of Agricultural Management Systems (GLEAMS), the consequences, in terms of sediment yield and phosphorus export, of hazelnut tree cultivation were estimated on different areas of the basin with and without the application of a best management practice (BMP) that consists of growing meadow under the trees. The GLEAMS results were successively extended to basin scale thanks to the application of a purposely designed regression model and of a GIS. The main conclusions can be summarized as follows: The effectiveness of the above-mentioned BMP is always greater for erosion reduction than for particulate P reduction, whatever the slope value considered; moreover, the effectiveness with reference to both particulate P and sediment yield production decreases as the slope increases. The proposed approach, being completely distributed, represents a considerable step ahead compared to the semidistributed or lumped approaches, which are traditionally employed in research into tools to support the decision-making process for land-use planning aimed at water pollution control.     

ESTIMATING THE BENEFITS OF PHOSPHORUS POLLUTION REDUCTIONS: AN APPLICATION IN THE MINNESOTA RIVER1

ABSTRACT: In order to make economically efficient decisions about water quality improvements, data on both the costs and benefits of these improvements is needed. However, there has been little research on the benefits of reducing phosphorus pollution which implies that policy decisions are not able to make the comparison of costs and benefits that is essential for economic efficiency. This research attempts to ameliorate this situation by providing an estimate of the benefits of a 40 percent reduction in phosphorus pollution in the Minnesota River. A 1997 mail survey gathered information on Minnesota residents'use of a recreational site on the Minnesota River, the Minnesota Valley National Wildlife Refuge, and their willingness to pay for phosphorus reductions in the Minnesota River. The random effects probit model used in this research to investigate household willingness to pay for phosphorus pollution reductions in the Minnesota River incorporates recent innovations in nonmarket valuation methodology by using both revealed and stated preference data. This model estimated annual household willingness to pay for phosphorus reductions in the Minnesota River at $140. These results may be used in combination with cost estimates to determine the economic efficiency of phosphorus clean up.     

嘉陵江南充段水质监测分析与综合评价

本文依据南充市2011年~2013年嘉陵江流域水环境监测统计资料,采用单因子评价法和综合污染指数法分析与综合评价嘉陵江南充段水质污染特征和现状。结果表明,研究河段内的清泉寺、小渡口和李渡断面总氮含量超标属于地表水Ⅳ类水体,超标倍数年均值分别0.21、0.35、0.37,其他监测项目符合Ⅲ类水质标准,均属于轻度污染。彩虹桥断面总氮、总磷、氨氮、CODMn和BOD5含量超过Ⅲ类标准,均在Ⅳ~Ⅴ类范围,属于中度污染。综合分析嘉陵江南充段,水质主要污染指标为总氮,综合污染指数为0.38,水质综合评价结果属轻度污染。该评价结果能为嘉陵江流域的水环境保护和科学治理提供依据。     

Eutrophication of Lake Waters in China: Cost, Causes, and Control

Lake water eutrophication has become one of the most important factors impeding sustainable economic development in China. Knowledge of the current status of lake water eutrophicatoin and determination of its mechanism are prerequisites to devising a sound solution to the problem. Based on reviewing the literature, this paper elaborates on the evolutional process and current state of shallow inland lake water eutrophication in China. The mechanism of lake water eutrophication is explored from nutrient sources. In light of the identified mechanism strategies are proposed to control and tackle lake water eutrophication. This review reveals that water eutrophication in most lakes was initiated in the 1980s when the national economy underwent rapid development. At present, the problem of water eutrophication is still serious, with frequent occurrence of damaging algal blooms, which have disrupted the normal supply of drinking water in shore cities. Each destructive bloom caused a direct economic loss valued at billions of yuan. Nonpoint pollution sources, namely, waste discharge from agricultural fields and nutrients released from floor deposits, are identified as the two major sources of nitrogen and phosphorus. Therefore, all control and rehabilitation measures of lake water eutrophication should target these nutrient sources. Biological measures are recommended to rehabilitate eutrophied lake waters and restore the lake ecosystem in order to bring the problem under control.     

沱江富顺段水质分析及污染状况研究

为了解沱江富顺段水质情况,采用相应的国家标准方法对沱江水体的氮、磷、化学需氧量、生化需氧量等指标进行监测。3个监测断面TN、TP的平均浓度分别为3．31mg／L、0．247mg／L,其中TN含量超标3倍以上,TP含量超过标准的1．2倍,建议相关部门应在河流平水期和枯水期严格控制氮、磷的排放,可通过调高工业废水、污水处理厂氮、磷排放标准,缓解沱江氮、磷污染程度。     

MFAM模型在河流水质污染模拟及预测中的应用

文中以时间序列分析为基础，介绍了均值生成函数这一崭新概念，并且经成份因子提取分析推导建立了模拟序列的数字模型（简记为MFAM），经对黄河下游花园口断面的1988-1989年实测水质污染指标溶解氧（DO），氨氧，化学耗氧量（COD），五日生化需氧量（BOD5）等序列模拟，结果表明MFAM模型能较好地模拟河流水质污染指标的变化趋势，拟合平均误差只有5.2-6.4%，MFAM模型应用于预测1990-1991年水质污染指标变化，结果表明预测精度达85%以上，文中最后得出结论：MFAM模型应用于河流污染模拟和预测，是完全可行且十分方便。     

拉萨河流域高寒湿地水质影响因子分析

西藏高寒湿地在生态平衡、生态建设和经济社会发展中发挥着重要作用。本文以西藏拉萨河流域内各个典型高寒湿地为研究对象,通过系统聚类法和综合污染指数法,对流域内各项水质指标进行综合分析和评价。结果表明：各个湿地的总N、Cu元素含量都超出了Ⅰ类水质标准;总P、Zn没有超标;Mn元素含量除了塘嘎郭湿地超标3倍外,其他均小于国家标准;Fe元素含量除了塘嘎郭湿地超标7倍外,其他均小于标准。总N、总P、pH值、Cu、Fe等因子对拉萨河流域内各个高寒湿地水质污染贡献最大。拉萨河水体有机污染较重,其余各个湿地有水体富营养化的趋势,同时流域内湿地独特的自然因素造成该流域内重金属污染偏高。对策建议包括应加大对城市污水的治理,加强流域内及周边矿藏资源的开发管理等。