人工湿地生物降固池对悬浮物及总氮的净化效果

通过植物泥培筛选实验、植物密度实验和水力停留时间优化实验对4种沉水植物进行筛选并研究了植物的最佳种植密度和生物降固装置对水体悬浮物和总氮的净化效果。结果表明：穗花狐尾藻适应能力较强，在北方冬季低温环境下仍能继续生长；种植密度为100株·m-2的穗花狐尾藻对悬浮物的吸附和截留作用最明显；生物降固装置最佳HRT为6~8 h。在HRT为6 h条件下，植物组对悬浮物的去除率为78.6%，比对照组高39%；总氮去除率为8.9%，说明生物降固装置可以有效截留、吸附悬浮物，但在较短HRT条件下对总氮吸附作用不明显。悬浮物达到同样去除效果，生物降固装置比自然沉降需要的时间少2~4 h。同时，种植水生植物的生物降固装置对总氮有一定的去除效果，降低人工湿地进水氮负荷。

Removal efficiency of suspended solids and total nitrogen in aquatic plants settling pond

Through plant screening experiments, best plant density experiments, and hydraulic retention time (HRT) optimization experiments, Myriophyllum spicatum L. was selected from four species of aquatic plants for its strong ability to adapt to low water temperature. The best HRT was 6 to 8 h. Under the condition of a HRT of 6 h, plants were planted at a density of 100 plants per square meter,and M. spicatum L. affected the adsorbtion and interception of SS the best. Under the same condition, the SS removal rate was 78.6%, whereas the SS removal rate of the control group was 39% lower. The total nitrogen removal rate was 8.9%, indicating that aquatic plants can effectively adsorb and intercept SS, but their effect on total nitrogen adsorption was not obvious. To handle the same amount of water, HRT can be shortened 2 to 4 h when using aquatic plants rather than natural deposition.