扎龙湿地的水环境特征及其对珍稀水禽的影响

通过野外调查和室内分析,探讨了近年扎龙湿地的水环境系统的特征及对珍稀水禽的影响。结果表明:扎龙湿地是整个嫩江流域生态环境脆弱区,表现出整体退化的趋势。水质富营养化严重:各项指标(除CODMn外)的含量最高的时期都为Ⅴ级,远远大于国家对湿地水质Ⅱ级的规定。扎龙湿地水质特征存在年内变化和空间上的差异性。农业活动较频繁地区扎龙湖的水质污染最重。扎龙湿地水体中重金属各项指标都低于Ⅰ类水质标准,扎龙湿地底泥中Cu、Pb、Zn、Cd、Hg超过其背景值。常见水禽的食物———鱼体内重金属含量的平均值分别是水体中含量的数百倍。珍稀水禽体内也都不同程度地富集了一定的重金属含量。湿地的退化和重金属的富集应该引起相关部门的重视。

Properties of Hydrochemical in Zhalong Wetland and its Influence on Rare Species

By field investigation & laboratory analysis,the properties of hydro-environment of Zhalong wetland and its effect on rare waterfowl were discussed.Result shows that Zhalong wetland is a fragile zone of total Nenjiang River Valley and shows a trend of degradation.the wetland has a severe eutrophication status:the period of the highest concentrations for the indicators(except CODMn) are all Class Ⅴ;these indicators are much larger than that of the national regulations for water quality with Level Ⅱ on wetland.The agricultural zone shows a severest water pollution.The accumulation of heavy metal is less than I level,nevertheless,the content of Cu,Pb,Zn,Cd and Hg in substrate are far larger than background level.The heavy metal accumulated in fish-food of most rare species are hundreds folds larger than in water.And it shows that heavy metal accumulated in rare species to some extent too.More attention should be paid to the degradation of wetland.