贵阳南明河水中溶解有机质分子量的初步研究

采用高效液相色谱系统对南明河中的有机物含量及分子量的分布特征进行了研究。南明河有机物的分子量呈多峰状态分布，分子量分布从大于3500 Da到小于1000 Da的有机物都存在。分子量在1000 Da～3500 Da之间的有机物含量占比71％～88％，分子量小于1000 Da和大于3500 Da的有机物含量很小。从整个南明河来看，上游和下游的有机物的分子量相对比较大，而中游的分子量相对比较小。

Study on Molecular Weight Distribution of Natural Dissolved Organic Matter in Nanming River of Guiyang City

This paper adopts high performance size exclusion chromatography(HPSEC)to determine the molecular weight of DOM in Nanming River.The distribution of the molecular weight was studied with four fractions.There are large, medium -large, medium and small fraction, with MW>3 500 Da,3 500~2 000Da,2 000~1 000Da and <1 000Da.In which the most of dissolved organic matters had molecular weight within 1 000~3 500Da with percentage of 71-88, while the others were smal-lest.The dissolved organic matter in the beginning and ending of the river had the larger molecular weight, while in the middle of the river the organic matter had smaller molecular weight.