沱江流域成都段水/沉积物污染现状评价与相关性分析

EVALUATION AND CORRELATION ANALYSIS OF WATER/SEDIMENT POLLUTION STATUS IN CHENGDU SECTION OF THE TUOJIANG RIVER BASIN

沱江流域成都段人口密集,河流污染问题突出。近年来,沱江流域污染问题受到广泛关注,污染状况已得到明显改善。在2022—2023年3次现场调查的基础上,采用内梅罗综合污染指数法评价了沱江流域成都段上覆水及沉积物的污染状况,并探究二者的相关性,以期为沱江流域成都段以及长江水生态环境保护治理提供依据。结果表明:水体最主要的超标因子为TN和COD,内梅罗综合污染评价发现水体处于中重度污染水平;沉积物主要污染物为TN、TP、Cr,内梅罗综合污染评价表明沉积物处于轻中度污染水平;水体与沉积物多项指标呈较强相关性,其中水体总磷与沉积物无机磷呈显著正相关,相关系数为0.506。沉积物污染物对水体有极大影响,因此控制河流外源污染的同时,也应加大对河流内源污染的治理。

The Chengdu Section of the Tuojiang River Basin is densely populated and has prominent river pollution problems.In recent years,the pollution problem has received attention and the situation has been significantly improved.Based on three field investigations from 2022 to 2023,the current pollution status of the overlying water and sediments in the Chengdu Section of the Tuojiang River Basin was evaluated using the Nemerow integrated pollution index method based on field investigations.The correlation between overlying water and sediment was sought to provide a basis for the management of water ecological protection in the Chengdu Section of the Tuojiang River Basin and the Yangtze River.The research results showed that:the most important exceedance factors of the water body were total nitrogen and chemical oxygen demand.The Nemerow comprehensive pollution assessment indicated that the water body was in a moderate to heavy pollution level.The main pollutants of the sediment were total nitrogen,total phosphorus,and heavy metal chromium.The Nemerow comprehensive pollution assessment indicated that the sediment was at light to moderate pollution level.There was a strong correlation between water and sediment,among which the total phosphorus of water was significantly positively correlated with inorganic phosphorus of sediment,and the correlation coefficient was 0.506.Sediment pollutants have a great influence on the water body,so the control of river pollution from external sources should also increase the management of river pollution from internal sources.