土壤水溶性有机物吸着系数及其影响因素研究

Sorption Coefficients of Water-Soluble Organic Carbon in Soils From Eastern China

测定了中国中、东部地区 17种土类 45个表土样品中水溶性有机物的吸着系数、分子量分布、腐殖酸含量、粘土含量以及土壤pH值 ,分析了水溶性有机物吸着系数的分布、地域分异和影响吸着系数的主要因素。结果表明 ,中国中、东部主要天然土壤类型A层水溶性有机物吸着系数在 0 .0 0 14～ 0 .0 2 84L g ,中位数为 0 .0 0 6 2L g;研究区吸着系数具有自北向南和自西向东递降的一般趋势。水热的地域分异是影响土壤A层Ks地域分异的根本因素 ,pH和WSOC分子量分布是直接影响Ks值的两个重要因素。

Using the procedure of Multiple-Water-Ratio, sorption coefficients (Ks ) of water-soluble organic carbon (WSOC) of 45 soil samples collected from eastern China were determined. Also, content of total organic carbon, humic acid, fulvic acid and clay of the samples together with molecular distribution of WSOC were determined. It was found that the Ks values range from 0.0014?L/g to 0.0284?L/g with a median of 0.0062?L/g. Statistical analysis shows that there is a decreasing trend in Ks from north to south and from east to west in the studied area. No significant correlation coefficients were found between Ks and content of content of total organic carbon, humic acid, fulvic acid and clay of the samples. Molecular size distribution of WSOC and soil pH were found to be the primary factors influencing the Ks.