重污染河流多源污染识别及环境背景值的确定——以宿州奎河氨氮为例

重污染河流因为受到多种人为污染的影响,确定其环境背景值难度很大。本文利用正态概率分布图和迭代标准差方法对奎河宿州段河水氨氮含量进行了分析,获取了奎河河水氨氮多源污染特征并确定了其环境背景值。结果表明,奎河河水氨氮主要来自于自然背景、农业污染、工业-生活污染,其环境背景值范围为0.52~1.08 mg/L。与区内其他河流河水分析结果的对比表明,直方图和正态概率分布图可以有效用于污染的多源识别与环境背景值确定,但利用迭代标准差方法估算环境背景值需要保证大部分样品未受到污染影响。

Identification of Multi-source Pollution and Determination of the Environmental Background Value of a Heavily Polluted River: a Case Study of NH4+-N in the Kuihe River, Suzhou

Determination of the environmental background value of a heavily polluted river is difficult because it has undergone multi contributions from anthropogenic activities. In this study, normal probability plot and iterative 2 sigma technique have been applied to the NH₄⁺-N concentrations in Kuihe River water, Suzhou, for revealing their multi sources and determination of the environmental background value. The results indicate that NH₄⁺-N in the river water originated from natural, agricultural, industrial and domestic sources and the environmental background value was 0.52~1.08 mg/L. In comparison with analysis of the data from other rivers in the area, the histogram and normal probability plot are considered to be useful for multi-source identification of pollution and determination of environmental background value. However, most of the samples without pollution should be guaranteed if the iterative 2 sigma technique is applied to environmental background study.