官厅水库水质评价及时空变化特征

针对官厅水库水质评价缺乏时空整体性动态分析的问题，选取2010—2017年官厅水库7个断面的7项污染物指标监测数据，采用主成分分析法、反距离权重法、Spearman秩相关系数法对官厅水库开展水质评价与时空变化特征分析。结果表明:水环境中有机污染与可还原污染并存，以氮磷元素为主导致的水体富营养化是当前水库面临的最主要污染问题；官厅水库水质污染存在明显的区域性特点，出库区域水质较好，入库区域附近水质较差；年内不同时期官厅水库水质状况为汛期优于非汛期；2010—2017官厅水库总体水质变化情况波动较大，各断面水质年际变化呈现出不同规律。建议对水库水质实行分区管理，上游削减氮磷污染物的同时增大入库水量，入库区域扩大人工湿地。

Water quality evaluation and spatiotemporal variation characteristics of Guanting Reservoir

In view of the lack of two-dimensional holistic spatiotemporal dynamic analysis of water quality evaluation of the Guanting Reservoir, the monitoring data of seven pollutant indicators from seven sections of the Guanting Reservoir from 2010 to 2017 were selected to carry out the water quality evaluation and investigate spatiotemporal variation characteristics of the water quality of the Guanting Reservoir using the principal component analysis method, inverse distance weight method, and Spearman rank correlation coefficient method. Results show that organic pollution and reducible pollution coexisted in the water environment, and the eutrophication caused by nitrogen and phosphorus was the most important pollution problem in the current state. The water pollution of the Guanting Reservoir had obvious regional characteristics, with the water quality being better in the outlet area and being worse near the inflow area, and the water quality of the Guanting Reservoir was better in the flood season than in the non-flood season. The overall water quality of the Guanting Reservoir fluctuated greatly from 2010 to 2017, and the interannual variation of the water quality of each section showed different trends. It is suggested to implement regional water quality management, reduce nitrogen and phosphorus pollutants in the upstream while increasing the amount of water into the reservoir, and expand the artificial wetland in the reservoir area.