太湖流域典型河流含氮物消减速率研究

采用自主研发的原位培养装置，开展了太湖流域典型河流水体含氮物消减速率及其影响因素研究.结果表明，总氮和氨氮消减速率呈现显著的空间差异性（P<0.05），消减速率分别为（280.6±180.0）~（1458.8±725.7）mg/（m³·d）、（35.2±3.7）~（343.6±88.4）mg/（m³·d），但硝态氮消减速率（44.3±7.6）~（521.2±19.2）mg/（m³·d））无显著的空间差异性（P>0.05）.微生物作用下氮素消减速率为95.0~733.1mg/（m³·d），分别占含氮物总消减速率和总负荷的12.9%~50.3%和2.0%~13.4%，非微生物作用下氮素消减速率为180.0~996.7mg/（m³·d），占含氮物总消减速率和总负荷的49.8%~87.0%和7.4%~25.7%，说明污染物进入水体，短期内微生物作用对含氮物消减速率的贡献较低.氮素消减速率与TN、NO₃^-、SS均呈线性相关关系（P<0.05），说明TN、NO₃^-、SS在一定程度上是氮素消减作用的影响因素.

Study on reduction rates of nitrogen pollution in typical rivers of Taihu Basin

The reduction rates of nitrogen pollution in typical rivers of Taihu Basin were studied using a self - developed in-situ device. The reduction rates of total nitrogen and ammonia nitrogen were (280.6±180.0)~(1458.8± 725.7)mg/(m³·d) and (35.2±3.7)~(343.6±88.4)mg/(m³·d), respectively, which indicated significant spatial difference (P<0.05). The reduction rate of nitrate nitrogen had no significant difference (P>0.05) among the rivers, and the rate was (44.3±7.6)~(521.2±19.2) mg/(m³·d). The N reduction rates under the microbial and non-microbial actions were 95.0~733.1mg/(m³·d) and 180.0~996.7mg/(m³·d), accounting for 12.9%~50.2% and 49.8%~87.0% of the total N reduction rate and 2.0%~13.4% and 7.4%~25.7% of the total N load to the rivers, respectively, indicating that the contribution of microbial actions to the reduction of nitrogen pollutants was low in short-term after nitrogen into the rivers. The N reduction rates were positively correlated with the TN, NO₃^- and SS concentrations (P<0.05), which suggested TN, NO₃^- and SS might be the influencing factors for N reducing.