摘要
为了了解2000年以来中国南方大规模小水电建设普遍引起河流和水库水质污染的特征,研究选择具有代表性的桂北山区某小水电站作为研究对象,选定流域特征污染物水温、pH、溶解氧、悬浮物、化学耗氧量、五日生化耗氧量、氨氮、总氮、总磷、石油类、阴离子表面活性剂、粪大肠菌群12项指标进行研究。研究表明,研究区水电站水环境中总氮、COD、石油类等污染物呈现随暴雨"陡涨陡落"的污染特征,暴雨后水库成为上游各种污染源的‘汇’区;暴雨后造成总氮、总磷增加,使水库富营养化程度升高;由于挥发和吸附作用强,石油类有易被净化的运移特征;沿途两岸森林中大量腐殖质是水环境中化学耗氧量的主要来源;暴雨后库区的水中溶解氧相对较低,但尾水强力曝气作用使干流一定区域出现"氧过饱和"现象;暴雨后该水电站水库水温梯度较小,对河流生态环境影响较小。建议当地政府在暴雨期间加强水源地水质的监控,采取应急措施保障居民用水安全。
In order to understand to cause rivers and reservoirs water quality pollution by large-scale small hydropowers constructed since 2000 in south China, choosing one typical small hydropower station in mountainous area north in Guangxi as the research object and 12 kind of characteristics pollutants in this river basin such as water temperature, pH, dissolved oxygen(DO), suspended solids, chemical oxygen demand, 5 biochemical oxygen demand, ammonia nitrogen, total nitrogen,total phosphorus, petroleum, anionic surfactant and fecal coliform. The results show that chemical oxygen demand, petroleum pollutants and total nitrogen etc some pollutants present characteristics of 'steep steep rise fall' along with heavy rain. The reservoir of the hydropower station became a 'reservoir' of various pollutants in the upstream area.The eutrophication degree in the reservoir had a creasing tendency due to total nitrogen and total phosphorus increased after heavy rain.Petroleum were purged easily due to its highly volatile and absorption. Plenty of humus in the coastal forest along river could be a main source of chemical oxygen demand in water. There is a relatively low dissolved oxygen concentration in the reservoir water,but power water can make strong 'oxygen supersaturated'phenomenon in a certain area of the river due to aeration effect.The water temperature gradient in the reservoir is smaller, its effect is smaller to river ecological environment. The cumulative effect of water environment was caused by some reservoirs construction. Therefore,this research suggested that the local gov-ernment should strengthen monitor to water source quality, during the torrential rain, so that take emergency measures to ensure water quality safety.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2015年第S1期111-117,共7页
Environmental Science & Technology
基金
中国地质调查局地质调查项目:西南主要城市地下水污染调查评价项目资助(1212011121166)
关键词
暴雨
山区
水电站
水库
水环境
污染特征
heavy rains
mountain area
hydropower station
reservoir
water environment
pollution characteristics
