土壤中钙、镁的形态分析及提取序列的研究

本文采用改进的BCR三步连续提取法对河北某食道癌高发地土壤中钙、镁进行了形态分析及提取序列的研究。实验表明：该地区土壤中镁主要以残渣态形式存在（占总量的83.66％-88.36％），钙则受提取序列的影响很大，在第一提取序列中，以酸溶态为主（74.11％-83.38％）；第二提取序列中，以有机物结合态为主（78.12％-97.17％）；第三、四提取序列中，以氧化物结合态为主（87.49％-103％）。提取剂的加入顺序明显影响到钙的各个形态的真实含量。

Speciation Analysis of Calcium and Magnesium in Soil and Their Extraction Sequence

This paper applied the BCR Three - Step Continuous Extraction for speciation analysis of calcium and magnesium in soil as well as their extraction sequence in an area with high incidence of esophagus cancer in Hebei Province. The experimental results showed that magnesium mainly existed as residue in this area （accounting for 83.66%-88.36% of the total） . While the existence state of calcium depended on the sequence of extraction. It existed in the state of acidic dissolving as the first （74.11%-83.38%）, combination with organic matters as the second （78.12%-97.19%） and oxide as the third or forth （87.49% - 103% ）, respectively. The adding sequence of extractant affected the proportion of calcium in different existing forms.