锡林河流域水质时空分布特征研究

锡林河属于西北诸河流域。锡林河流域范围跨赤峰市、锡林郭勒盟两地，是我国内蒙古高原的代表性内陆河之一。为揭示锡林河水质时空分布特征，基于13个采样点、7个水质指标的监测数据，采用均值型综合污染指数法、单因子水质标识指数法对水质开展评价；结合主成分分析、聚类分析探讨水质时空分布特征的成因。结果表明：锡林河春、秋两季水质较好，夏季相对较差，影响夏季水质的主要因子为COD_Mn、COD和BOD₅；锡林河中游河段水质优于上游和下游。上游和中游河段水质超标主要由于畜禽养殖和农村生活带来的面源污染；下游河段水质超标的主要原因为污水厂尾水中的氮磷浓度较高。

Study on Water Quality Spatio-Temporal Distribution Characteristics of Xilin River Basin

Xilin River belongs to the northwest river Basin,and its basin spans Chifeng and Xilin Gol League,is one of the representative inland rivers in Inner Mongolia Plateau of China.In order to reveal the spatial and temporal distribution characteristics of water quality in Xilin River,the mean comprehensive pollution index method and single factor water quality identification index method were used to evaluate the water quality based on the monitoring data of 13 sampling sites and 7 water quality indexes.Combined with principal component analysis and cluster analysis,the causes of spatial and temporal distribution characteristics of water quality were discussed.The results show that the water quality of Xilin River is better in spring and autumn,but relatively worse in summer.The main factors affecting water quality in summer are COD_Mn,COD and BOD₅.The water quality of the middle reaches of Xilin River is better than that of the upper and lower reaches.The water quality exceeding the standard in the upper and middle reaches is mainly due to the non-point source pollution caused by livestock and poultry breeding and rural life.The high concentration of nitrogen and phosphorus in the tail water of the sewage plant was the main reason for the water quality in the lower reaches exceeding the standard.