珠江上游土壤与沉积物有机元素的含量与分布特征

以珠江上游南盘江流域为研究区，测定农田及非农田土壤、河流沉积物有机元素(C、H、N、S、O)的含量，探讨有机元素的多介质环境行为。结果表明：研究区农田土壤C、N、S的含量显著高于非农田土壤，H、O的含量在2种土壤中差异不明显。农田土壤相对较高的S含量和较低的C/N和N/S值，将最大限度地减少S缺乏。河流沉积物多数样点的有机指数均达到Ⅳ级(＞0.50)，处于有机污染状态。沉积物与农田和非农田土壤C含量正相关，但不显著，而沉积物与农田土壤N含量显著相关，沉积物与非农田土壤中的有机物质来源存在较大差异。

The Concentration and Distribution of Organic Elements in Soils and Sediments from Upstream of the Pearl River,China

The concentration of organic elements (C, H, N, S and O) in agricultural, non-agricultural soils and sediments were investigated from upstream of the Pearl River, China. The results showed that total C, N and S concentrations were closely correlated in agricultural soils and were significantly higher than those in non-agricultural soils. The differences of H and O contents in 2 kinds of soil were not significant. Agricultural soil would not be deficient in S due to high total S concentration and low ratios of C/N and N/S. For most sample sites, organic indexes of sediment have reached the grade Ⅳ (> 0.50), where were organic pollution. Total C concentration of sediment were positively correlated with that of agricultural or non-agricultural soils, and total N concentration of sediment was significantly positively correlated with that of agricultural soil. There were significant differences for the source of organic matter between sediment and non-agricultural soil.