渔洞水库水源地近年水质下降及其原因分析

Analysis on the Causes of the Recent Decline of the Water Quality in Yudong Reservoir

从1997年以来,渔洞水库水源地水质处于国家地表水Ⅱ—Ⅳ类之间,大部分年份属于三类水质,其中2013年为Ⅳ类水质,达不到国家饮用水标准,已严重威胁着城市居民的饮用水安全.根据多年水质监测资料分析,造成水源不达标主要是总氮和总磷超标,径流区水土流失严重等.本文系统分析水质下降原因,为渔洞水库水环境治理提供决策依据.

Since 1997 ,the water quality of the surface water in Yudong Reservoir’s water resource area has been among the national surface water grades of II to IV ,most of which are in Grade III .Only in 2013 did its water quality of the surface water reach to Grade IV .Thus ,the water quality of the surface water in Yudong Reservoir’s water resource area cannot meet the national drinking water standard ,which has been seriously threatening the safety of drinking water of Zhaoyang District’s urban residents .According to the data analysis of water quality monitoring for many years ,we find the major reasons are the total superscale of nitrogen and phosphorus of its surface water and the serious loss by run‐off soil in its runoff area ,etc .The reasons of the water quality decline are systematically analyzed in this essay so as to offer some decision‐making theory bases for improving the environment of Yudong Reservoir .