浑河河水及其沿岸地下水污染特征

选择沈阳地区重要河流浑河及其沿岸地下水进行定量分析,研究并探讨了包括无机物和有机物在内的水质综合污染特征。结果表明,浑河河水中氨氮、硝氮、亚硝氮和酚超过了地表水环境质量标准,最大超标倍数分别为15.8、1.5、82.4和1.8倍,检测出的11种卤代烃、氯苯和六六六等有机物均未超标。浑河沿岸地下水中氨氮、硝氮、亚硝氮、化学需氧量、酚和铅超过地下水质量标准,超标率分别为31.6%、10.5%、26.3%、36.8%、47.4%和26.8%,检测出的4种卤代烃和六六六等有机物均未超标。河水及其沿岸地下水中的污染物,尤其是有机污染物种类和浓度高值基本出现在城西的谟家—大祝断面之间。浑河水质主要受城市工业废水、居民生活污水排放的影响,沿岸地下水的污染来源包括工业生产或农村居民生活造成的地表污染物垂直入渗式的点源污染、浑河水侧向渗透补给式的线源污染以及农药化肥使用产生的面源污染,而有机污染物主要通过点源污染地下水。浑河各区段的使用功能、包气带岩性及沿岸水源地开采井布局等因素都为受污染的河水对沿岸几百米范围内的浅层地下水的补给提供了条件,造成浅层地下水的污染,对当地生态系统及人类健康构成潜在威胁。

Contamination characteristics in surface water and coastal groundwater of Hunhe River

The pollution characteristics of Hunhe River and its costal groundwater were investigated which included inorganic and organic index. The results indicate that concentrations of ammonia, nitrate, nitrite and phenol in Hunhe River exceeded the National Environmental Quality Standard for Surface Water, and the maximum exceed multiple was 15.8, 1.5, 82.4 and 1.8, respectively. Ammonia, nitrate, nitrite, COD, Pb and phenol in coastal groundwater of Hunhe River exceeded the Environmental Quality Standard for Groundwater and the exceed ratio were 31.6%, 10.5%, 26.3%, 36.8%, 47.4% and 26.8%, respectively. But organic matters which were detected in the river and coastal groundwater such as chlorobenzene and benzex didn't exceed the standard. The pollutants especially organic pollutants were various and high-concentration from Mo jia-Da zhu section. The surface water quality was mainly affected by the city industrial wastewater and domestic sewage. The pollution in coastal groundwater was due to point source pollution vertical infiltrating caused by industrial production or rural residents activities, line source pollution by lateral infiltration recharged from river and non-point source pollution owing to the use of pesticide and fertilizer. Thereinto, organic pollution of groundwater was mainly on account of point source pollution. Some factors such as river using function, vadose zone lithology and layout of exploitation well along the river made pollutant transportation from the polluted river to shallow coastal groundwater within a few hundred meters which poses a great potential threat to ecosystem and local population.