大亚湾沉积物中重金属元素背景值研究

A BACKGROUND VALUE STUDY ON HEAVY METAL ELEMENTS IN THE SEDIMENTS OF DAYA BAY

根据大亚湾的自然条件认为,大亚湾沉积物的物质来源是其周围集水区的岩石风化壳,并计算了其风化壳中重金属元素的平均丰度值;又根据沉积物的粒度和深层沉积物重金属元素的含量资料,列方程计算出湾内沉积物中重金属元素的平均含量,根据这两组数据,确定该区域内重金属元素的平均背景值。再通过粒度关系,计算得出大亚湾内各站沉积物中重金属元素的背景值。应用此结果和大亚湾沉积物重金属元素实测结果,计算了由人为影响带入沉积物中的重金属元素含量,了解其受污染的程度。

By research and computation the paper determines the mean value ofheavy metal elements in rock weathered shells in the catchment area around Daya Bay. At the same time it has set up an equation group from grainsizing data of the sediments, and the data of heavy metal element contents in deep strata sediments which were taken from 13 sampling stations inside Daya Bay in 1988, and computated the mean contents of heavy metal elements in sediments of the bay. According to the two data groups,mean background value for heavy metal elements inside the area was determined. On ground of that and again by grainsize relation, a square equation was arranged, computating the background value for heavy metal elements of each station in the bay. By application of these results and the measured results of heavy metal element contents of the sediments in Daya Bay of 1988, a formula of mathematical relationship was set up,and the heavy metal element contents in the sediments which were carried through manmade effects were computated, understanding the extent of pollution.