南黄海表层沉积物物质来源的逐步判别分析

Stepwise Discriminant Analysis Used for Discriminant Sediment Source of the South of the Yellow Sea

1998年6月,获取南黄海表层沉积物样品61个,黄河、长江中、上游细粒泛滥平原沉积物样品24个。在对后者17个地球化学指标测试的基础上,利用逐步判别分析方法,筛选出7个指标(Ti、Cu、K_2O、Zn、Na_2O、Al_2O3和CaO),做为识别黄河、长江物质组成的有效参数,并构造黄河、长江两个物源端元的判别函数Y1和Y2。利用判别函数,分别计算出南黄海61个表层沉积物的函数值,进而对其物源属性进行识别。判别结果表明,南黄海表层沉积物按物源属性分为三大区:A—长江物质优势区;B—黄河物质优势区;C—长江、黄河物质混合区。

In June,1998,61 surfacial sediment samples in the south of the Yellow Sea and 24 fine-grained sediment samples of overbanks of the Yellow River and Yangtze River were collected.Of the 17 elements analyzed for all samples,7 elements (Al_2O_3,CaO,Na_2O,K_2O,Cu,Zn,Ti) were selected as valid parameters for distinguishing substance of the Yellow River from the Yangtze River using the stepwise discriminant analysis.Two discriminant functions,Y1 and Y2,were constituted utilizing the seven elements to calulate the two fuctional values for each of 61 surface sediment samples,on the basis of which the derived natures of the samples were distinguished.The result of the discriminant analysis demonstrates that the whole surface sediment region of the south of the Yellow Sea can be divided into three sub-regions with different sources.the first is sub-region dominated by the Yangtze River's source,the second is one by the Yillow River's source and the third is sub-region mixed by the Yellow and Yangtze River's sources.