查干湖湿地水环境演变特征分析

The Evolutional Characteristics of Water Environment of Chagan Lake Wetland

查干湖湿地是吉林西部重要的生态屏障,分析其水环境演变特征,可为保障其水环境安全提供科学依据。利用1982~2011年的水位资料和1985~2011年的水质资料分析其水环境演变特征,采用卡尔森指数法和模糊综合评价法对查干湖湿地进行综合营养状态和水质状况评价。结果显示引松工程通水后湿地水位得以恢复并稳定在129.8~130.3 m;20世纪80年代末湿地水环境大幅改善,水体盐碱化、富营养化、有机污染得以缓解,但2006年以来水质碱化和有机污染加剧,水质由Ⅲ类演变为IV类。现阶段农田退水缓解了主湖区的碱化且暂未加剧其水体富营养化。查干湖水受流域陆源排放、湖泊内源释放及水文情势等多重因素的交互作用,呈以磷素为限制的中营养状态,应控制区域生活污水和畜禽粪便的污染以保护其水环境健康。

Chagan Lake wetland is an important ecological barrier of the western Jilin Province. Analyzing the evolutional characteristics of the water environment will provide a scientific basis for the protection of the water environment security. The evolvement of water environment was comprehensively studied through analyzing the water level data from 1982 to 2011 and the water quality data in 1985-2011. Carlson trophic state index(TSI) and the fuzzy comprehensive evaluation method were used to assess the eutrophication level and the water quality. The results showed the water level was recovered and stabilized at 129.8-130.3 m after the operation of the channel transferring water from Songhua river to Chagan Lake. Water salinization, eutrophication,organic pollution were mitigated and the water environment improved considerably in the late 1980s, but the trend of alkalization and organic pollution has became serious since 2006 and the water quality evolved fromⅢ category to IV category. The trend of eutrophication has been relieved since 2006.Agriculture drainage has relieved the water salinization and hasn't aggravated the level of eutrophication in Chagan Lake temporarily.The water quality of Chagan Lake is accross-affected by terrestrial emissions in the catchment, endogenous releases and hydrological regimes and exhibits a remarkable phosphorus limited middle nutrition. Sewage and animals' feces pollution should be controlled to protect the water environment health.