扎龙湿地底泥沉积物重金属污染评价

对扎龙湿地底泥-水体以及丹顶鹤体内的重金属Zn、Cd、Cu、Pb、Cr进行分析。结果表明,扎龙湿地底泥富集重金属状态较明显,5种金属的平均质量分数均远超过该地区土壤背景值。各金属的富集程度为Zn>Cu>Pb>Cr>Cd。扎龙湿地底泥重金属元素特征在空间上存在明显的差异性。工、农业活动较频繁的林甸县和富裕县所属的湿地区的底泥污染最重,具有很强的潜在生态风险,湿地核心区内的底泥重金属属于轻微-中等生态风险程度。Zn是扎龙湿地栖息的东方白鹳和丹顶鹤体内富集的主要元素,Zn的富集,粪便>羽毛>蛋壳。除了Zn富集明显外,其他重金属富集顺序为Cu>Cr>Pb>Cd,各种元素在2种水禽不同附属物中质量分数高低顺序与Zn一致。

Potential Ecological Risk Assessment of Heavy Metals in Substrate of Zhalong Wetland

By in-situ investigation and datum analysis, the contents of five typical heavy metals in the sub-strate of Zhalong wetland and in the water body were discussed. Results showed that Zhalong was a vul-nerable zone of west Songnen Plain, which had being a trend of degradation. The measured contents werefar larger than background level, which ranked as: Zn>Cu>Pb>Cr>Cd based on the measured concen-tration. In addition, the concentration ions existed obvious spatial variation as following rules, and poten-tial ecological risk index were larger where was adjacent to agricultural activity area or chemical plant, i. e.the risk index in Lindian county was above 600, and below 300 in core area. As a portion of wetland sys-tem, the rare species were influenced to some extent too. It is should be drawn enough attention for thedegradation of wetland.