小流域水环境规划方法框架及应用

在界定小流域概念的基础上,将流域分析方法引入到小流域水环境规划中,初步建立了典型小流域水环境规划方法框架.该方法遵循了污染物在小流域中的运移规律,针对影响河流水质的主要因素--"源头-途径-末端-汇",采取了相应的对策措施,能够反映出不同污染物对流域水质的影响规律.以云南省寻甸县牛栏江小流域为例,在对其水环境现状分析及发展趋势预测的基础上,进行了水污染控制单元的划分,以确定重点污染控制区域和敏感地带,同时制定了其总量削减计划,提出了以水土流失防治、点源和面源控制、河道生态修复及河流内源疏浚为主体的水环境规划方案.该方案实施后,COD_Cr和NH₃-N可分别削减1 857和125 t/a,达到了预期目标. 

The Framework and Its Application of Water Environmental Planning for the Small Watershed

Based on the definition of the conception of the small watershed, the theory of the watershed analysis was inducted to water environmental planning and a framework of the water environmental planning for the small watershed was proposed. The framework followed the rule of the contamination transfer, which reflected the effect of the contamination on the water quality. The pollution control countermeasures including source control, route eliminating, endpoint control and sink dredging-up were adopted. The small watershed of the Niulanjiang River in Yunnan Province, Southwestern China was taken as a case study. Based on the analysis and prediction of the water environment, the water pollution control unit of the Niulanjiang River was divided and the key pollution control reach was set up. The plan of total quantity control was made. Then the soil losses prevention, point and nonpoint sources control, ecological restoration of rivers and dredging-up of sullage were recommended for water pollution control in the small watershed. After the implement of the scheme, the eliminating amount of CODCr and NH3-N is 1 857 and 125 t/a respectively, through which the anticipative aim of environmental capacity could be attained.