台湾海峡南部沉积物中某些重金属元素的背景值

A background survey on heavy metal elements in sediment of southern Taiwan Strait

本文根据台湾海峡南部海区沉积物中Mn、Co、Ni、Cu、Zn、Cd、Pb等重金属元素含量、中值粒径和细粒组分的等值线平面分布的相似，三者从岸到海和沿岸文化特征的一致，以及重金属元素之间、其和粒度组分之间的显著相关，建立四组估算重金属元素背景值的回归方程，并以统计检验方法择优。结合沉积物样本的测定值和回归方程的计算值，选取总体均值μ估计值95％置信区间作为重金属元素的平均背景位区间。以细粒组分及其对应的个体y值95％置信区间上限／下限为变量求得的回归方程，可对不同位组的个体样本中重金属元素的背景值区间作出估计。这一模式提供的背景值区间反映了沉积物的区域性和拉组实况；其上限可作为检验不同粒组的沉积物有否受重金属元素污染的评价标准。

Based on the similarity of the isopleths of horizontal distribution of some heavy metal elements (such as Mn, Co, Ni, Zn, Cd, Cu, Pb, etc.), Md., and fine grain component in the sediment of southern Taiwan Strait, the agreement of the fluctuation characteristics of the samples at stations seaward from the coast or along the coast, the significance of correlation coefficients between these elements and find grain component and between metals themselves respectively, 4 sets of regression equations are set, and the optimum one is selected by using statistical test, by which the background values of heavy metal elements will be found.on consideration of both the measured mean value of samples and the estimates obtained from the optimum regression equation, 95% confidence interval of mean of population is taken as the average background value interval, while the regression equation is set by the variables, the fine grain component and its corresponding value of upper/lower limits of 95 % confidence interval of individual y, giving the background value interval of heavy metal elements in sediment of different grain composition. And the upper one can be taken as the criterion for evaluating the degree of heavy metal pollution in the sediment.