确定不同环境下土壤硒的活性稳定性及安全阈值

The Determination of Activity and Stability as well asthe Safe Threshold Value of Selenium inthe Soil under Various Circumstances

本文通过对我国现有４１个类型土壤硒的迁移、转化地球化学特征的分析和不同形态硒在食物链中传递的物质过程进行的跟踪研究基础上，用主因子分析法在影响土壤硒含量的诸因素中，选择出４个主因子，并对我国４１个土类进行了区划，找到了土壤硒的区域分异规律。最后针对不同功能区制定了土壤中总硒及水溶性硒含量的安全阈值，这为制定土壤硒环境质量标准提供了科学依据。

Having analyzed the earth chemical features of the migration and transformation of selenium in 41 types of soils in China,and followed the tracks of selenium in various forms when ittransmited through the food chain,the authors have determined the activity and stability of selenium in the soils. By applying principal factor method,the 4 principal factors that affect the selenium content of the soils have been determined and the 41 types of soils have beend divided into districts.The rule of regional differentation of selenium in the soils have been found out.As a result,the safe threshold values of total selenium content of the soils a ccording to various functional regions have been worked out,which provided the scientific basis for laying down the environmentalqulity cri-teria of selenium in the soils.