共查询到20条相似文献,搜索用时 62 毫秒
1.
随着台湾经济的发展,水域更进一步受到污染。据1987年对台湾45条主要河流调查,清洁河流20条占44.4%,轻度污染6条占13.3%,中度污染12条占26.7%,严重污染7条占15.6%。从河流污染长度来看,总长2820.8公里,清洁河段1998.7公里占70.9%,轻度污染180.9公里占6.4%,中度污染319.7公里占11.3%,严重污染321.1公里占11.4%。为保护水资源,台湾当局已将水质保护目标分为3阶段进行。第一阶段到1991年,企业排水达到现有排放标准,总污染负荷削减24%。第二阶段到1997年,使河流得到合理使用,各流域达到功能区水质标准。第三阶段到2007年,河流纳污量不超过其自 相似文献
2.
3.
4.
5.
6.
一、我国水污染的特点由于历史欠帐过多和众多的主客观原因,纵观全国,水污染仍呈发展趋势。传统的污染物(COD、BOD)未能控制住,富营养化和有毒化学物质的污染都相继增加;点源污染未有效控制住,非点源污染在一些地区又突出起来。由于80%以上的污水未经有效处理就直接排入水域,已造成我国1/3以上的河段受到污染,90%以上的城市水域严重污染,近50%的重点城镇水源不符合饮用水标准。水资源不合理的开发利用,水污染的不断加重,引起了普遍缺水和严重的生态后果。造成我国水污染严重的主要原因是:许多企业工艺落后,管理水平较… 相似文献
7.
概述了西辽河流域双辽境内的自然环境状况,论述了西辽河水污染现状,对污染源进行了详细分析,提出了西辽河水污染防治对策。 相似文献
8.
论中国水污染防治的战略对策 总被引:1,自引:0,他引:1
论中国水污染防治的战略对策CommentonCountermeasureStrategyofTreatmentofWaterPollutioninChina.沈光范纵观全国水环境污染仍呈发展趋势。传统的污染物(BOD、SS)未能控制住,富营养化和有毒... 相似文献
9.
10.
建国以来,特别是1973年召开的第一次全国环境保护会议以来,全国各地在水污染防治方面,做了大量工作,使我国在国民经济迅速发展的情况下,水体污染程度并未同步发展,而且在水污染防治工作中还积累了不少经验,归纳起来,我认为可概括为保、截、治、排、引、管、用等七个方面。 相似文献
11.
12.
四川升钟水库水质评价及污染负荷分析 总被引:2,自引:0,他引:2
选取高锰酸盐指数(CODMn)、五日生化需氧量(BOD5)、总氮(TN)、总磷(TP)4项监测指标,采用单因干评价法、综合污染指数法、内梅罗污染指数法、模糊综合评价法及水质标识指数法对升钟水库2004~2010年水污染特征进行分析与评价,结果表明:水质标识指数法比较适合升钟水库水体富营养化评价;单因子水质标识指数显示,水库主要污染物为总氮(TN)、总磷(TP),基本呈现富营养状态;2008年水质最差,2010年水质达到Ⅱ类标准;7年Iwq的平均值Ave(Iwq)=3.393,Ave(Iwq)未达到国家Ⅱ类水质标准。近7年综合水质标识指数(Iwq)在不同时点上具有高-低演化规律,总体趋向好转。通过计算2006年N、P污染负荷,TN、TP入库主要源于水产养殖,其贡献率分别为:55%、82%,升钟水库TN、TP是合理容量的1.97~2.32倍。应严格控制水库网箱肥水养殖。研究结果对指导升钟水库水污染防治与水资源管理具有重要的意义。 相似文献
13.
14.
会理污灌区重金属污染的调查,评价及防治对策 总被引:4,自引:0,他引:4
本文调查、评价了会理县锌矿污灌区内水、土、作物的重金属污染状况。调查结果表明:污灌区内土壤、作物重金属污染严重,尤以镉污染突出。作物中镉含量与距污染源距离呈负相关(r=-0.995)。镉在水稻植株各部位的分布,以根系含镉量最高,茎叶次之,谷粒最少。评价结果表明农灌水的污染程度不大,土壤中Cd、Zn、Pb污染是土壤污染的主要表现,水稻的污染较玉米更为严重。Cd已对人体健康构成潜在危害。本文还针对污染区的重金属污染提出了相应的防治措施 相似文献
15.
Sources of water pollution and evolution of water quality in the Wuwei basin of Shiyang river, Northwest China 总被引:3,自引:0,他引:3
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced. 相似文献
16.
田秀英 《中国环境管理干部学院学报》2002,12(1):38-39
本文在充分分析造成供水管网二次污染各种原因的基础上,参考国内管网清洗技术,结合秦皇岛市供水管网现状,提出了减少供水管网污染的措施。 相似文献
17.
18.
19.
Watkins W. Miller Chauncey T. K. Ching John F. Yanagida Paul Jakus 《Environmental management》1985,9(1):1-6
Regulation and control of agricultural water pollution is unique and difficult to accomplish. Water quality standards are often proposed without adequate consideration of the overall economic impact on agricultural production. This article illustrates how economists and physical scientists can cooperate to develop appropriate control strategies for agricultural water pollution. Data provided by physical scientists and economists are used in a linear programming model to describe salt discharge as a function of water management, production levels, and an associated effluent charge. Four water management activities were chosen on the basis of different costs of production (including a parametrically varied effluent charge), water requirements, alfalfa yields, and levels of salt discharge. Results indicate that when the effluent charge is low (<$0.20/metric ton salt discharged), maximum production with maximum salt discharge is most profitable. As the effluent charge is increased ($0.20–$0.40/metric ton salt discharged), it becomes progressively less profitable to produce alfalfa at maximum levels of pollutant discharge. When the effluent charge is >$0.40/metric ton salt discharged, alfalfa production is no longer economically feasible. An important aspect of this approach is that it permits policy makers to identify explicitly the relationship between the environmental standard and the effect on agricultural production. 相似文献
20.
沱江水质污染特征及防治对策 总被引:1,自引:1,他引:1
本文以沱江水质监测资料为依据,揭示了沱江水质污染特征及其时空变化视律。针对沱江存在的水环境问题,从宏观上提出了防治水质污染的对策。 相似文献