吉林西部查干湖湖泊沉积物中元素的空间变化及其环境意义

The spatial distributions of elements in sediments of lake Chagan in west Jilin Province

对吉林省西部查干湖湖泊沉积物中元素的空间分布特征及其潜在生态危害进行了研究。得出同吉林西部土壤中元素平均值相比,查干湖湖底表层底泥中明显富Ca、Cl、Mg、Hg、Cd,而贫K、U、Al、Co、Na、有机碳,其中Al2O3、MgO、Fe2O3、CaO、As、Hg、Cr、U、Cu、Zn、Cd、Se、Co、Ni、Th、Mn、N、P等主要来自岩石或土壤的风化作用,表层底泥中Hg、Cd、As、Cr、Cu、Zn、Pb的潜在生态危害性均很小;在湖泊沉积柱剖面中,Fe2O3、Cu、Zn、Co、Ni、Cr、Cd具有相同的变化趋势,不同沉积柱中沉积物具有相似的来源,沉积柱中重金属的潜在生态危害程度也很小,预示着在垂直方向上进入查干湖水体的重金属污染物数量也很少;查干湖的水体环境质量较好。

The spatial distributions of elements and their potential ecological risks in sediments of lake Chagan in the western Jilin Province were investigated. It was concluded that Ca,Cl,Mg,Hg,Cd were enriched and K, U, Al, Co, Na, organic carbon were depleted in the surface sediments of lake Chagan when compared with those averaged values of soils from mid - west Jilin Province. Among the elements, Al2O3 , MgO, Fe2O3, CaO, As, Hg, Cr, U, Cu,Zn, Cd, Se, Co, Ni, Th, Mn, N, P were derived from the weathering of rocks and soils. The potential ecological risks of Hg, Cd, As, Cr, Cu, Zn in surface sediments were less. In lake sediment profiles, Fe2O3, Cu,Zn, Co, Ni,Cr,Cd were employed the same variation trends. The sediments from different sediment profiles came from the similar source. The potential ecological risks of heavy metal in sediment profiles were also less, which implied that the amounts of heavy metals vertically charged into the water of lake Chagan were little. The water environmental quality of lake Chagan is quite good and satisfactory.