西藏土壤中氟的含量及其分布

Contents of Fluorine in Soil and Their Distribution in Tibet

分析了采自西藏地区２０５个样品的土壤含氟量．研究结果表明，西藏土壤中氟的平均含量为５０６ｍｇ·ｋｇ－１，明显高于全国４４０ｍｇ·ｋｇ－１的平均水平．西藏土壤中氟的含量呈由东（南）→西（北）逐渐降低的总趋势，这与西藏植被和土壤地带性的演替变化方向一致．多重分析表明，西藏不同母质上发育的土壤氟的含量差异较为显著，以基性火成岩发育的土壤含氟量最低．土壤中有机质的含量和ｐＨ值影响着土壤中氟的迁移和累积．聚类分析把氟与锰、铜、钒聚为一类，这与这些元素在表生环境中都具有溶解度高、易移动、高度分散和易被富集有关．

205 Samples of soil were taken from different sits in Tibet and analysed for their contents of fluorine in soil.The results showed that the average content of fluorine in soils from Tibet was 506mg·kg^-1 and significantly higher than the average national level of 440 mg·kg^-1.The content of fluorine in soil was distributed in Tibet with a total trend of gradually decreasing from the southeast to the northwest that was consistent with the direction of changes in the zonal successions of vegetation and soil in Tibet.The cluster analysis showed that the variation of the content of the fluorine in the soil developed from the difference soil parent material in Tibet is very striking.The content of fluorine in the soil developed from the soil parent material of basic igneous rock is outstandingly lower than that in the soil developed from any other soil parent material.The migration and concentration of fluorine in soil are affected by organic matter and pH value in soil.The cluster analysis showed that Mn,Cu,V and F are classified one group,which is related to the elements easy solving,migrating and concentrating in the surface environment.