子牙河水系河流氮素组成及空间分布特征

选取海河流域子牙河水系典型污染河流为研究对象,对河流水体与沉积物中氮素组成及空间污染特征进行了研究.结果表明,子牙河水系各河流为高NH+4-N污染,TN浓度均值为31.28 mg·L-1,超过国家地表水Ⅴ类标准15倍,NH+4-N浓度最高,占TN的质量分数为79%,总有机氮(TON)次之;表层沉积物中含氮物质主要以有机氮形式存在,平均含量为3.290g·kg-1,约为NH+4-N的4.5倍;子牙河水系水体中NH+4-N与TON、NH+4-N与t存在显著正相关(P<0.01),表层沉积物中NH+4-N、有机氮(SON)与TOC之间存在显著正相关(P<0.01);子牙河水系河流表层沉积物普遍处于有机污染状态,根据有机污染评价结果显示有机氮污染造成的影响要略高于有机碳,北澧河沉积物污染最为严重.

Forms and Spatial Distribution Characteristics of Nitrogen in Ziya River Basin

In order to research the spatial distribution characteristics and pollution condition of nitrogen in water and sediment, the Ziya River Basin was selected as the study area. The results showed: the average TN concentration of all water body samples was 31.28 mg·L^-1, which was 15 times higher than the V-class standard of national surface water, where the NH₄⁺-N accounted for about 79% of TN ratio, followed by total organic nitrogen(TON). The organic nitrogen was the major form to exist in nitrogenous substances of surface sediment; and the average concentration was 3.290 g·kg^-1, which was 4.5 times higher of NH₄⁺-N's. In the waters of Ziya River Basin, NH₄⁺-N had a significantly positive correlation with TON and t, respectively (P<0.01); as well as both NH₄⁺-N and sediment organic nitrogen(SON) were significantly positively correlated to TOC (P<0.01) in the surface precipitation. The surface sediment of Ziya River Basin was in the state of organic pollution, and Beili River was in the most serious status. It was worth mentioning that the influence of organic nitrogen pollution was just above the organic carbon's.