关键词: 污染负荷, 主要污染源, 水环境容量, 汉江中下游

Abstract: Based on the investigation and analysis of various pollution sources, pollution status quo in the middle and lower reaches of the Hangjiang River was analyzed with COD and NH3-N as index of pollution load, and main pollution sources were found. Choosing COD and NH3-N as main indicators, water environmental capacity was computed by one dimensional water quality model. Results indicated that the main pollution sources of the middle and lower reaches of the Hanjiang River were urban domestic sewage, scale livestock culturing and industry discharge; the pollution load discharged into the middle and lower reaches of the Hanjiang River was 340 572.15 t in 2015, most of which was COD; scale livestock culturing was the main pollution source to Qianjiang reach, and urban sewage for other reaches. According to the calculation result of the one-dimensional water quality model, the middle and lower reaches of the Hanjiang River have ample water environmental capacity of COD, but do not have enough residual water environmental capacity of NH3-N; the tributaries such as the Tangbai River, the Zhupi River and the Tianmen River both have low COD and NH3-N water environmental capacity.

Key words: pollution load, main pollution source;water environmental capacity, middle and lower reaches of Hanjiang River