浮床植物系统对富营养化水体中氮、磷净化特征的初步研究

以浮床空心菜(Ipomoea aquatica)、水芹(Oenanthe javanica)和无植物系统为对象,研究了其在富营养化水体中对N、P的去除及其N₂O的排放情况.结果表明,浮床植物系统对水体中N、P具有良好的净化效果,植物组织所累积的N、P量分别占各自系统去除量的40.32%～63.87%,说明植物的同化吸收作用是N、P去除的主要途径.换水周期内浮床植物系统中硝化反应进行充分,而反硝化反应相对缓慢,导致系统具有较高的NH₄⁺-N去除率,而产生NO₃--N累积.植物的存在降低了系统中N₂O的排放通量.生长较好的空心菜系统在换水前后平均N₂O排放量最低,为17.14μgN·m^-2h^-1,空白高达8.08μgN·m^-2h^-1,水芹为37.38μg N·m^-2·h^-1.

N and P removal characters of eutrophic water body under planted float

The study on the N and P removal and N2O release of eutrophic water body under planted float Ipomoea aquatica and Oenanthe javanica showed that planted float had a good effect on the removal of N and P from eutrophic water body. The bioaccumulation of N and P by the plants accounted for 40.32% approximately 63.87% of the N and P removal, respectively, suggesting that plant uptake was the main removal process. Within the treating period, there was a rapid and sufficient nitrification but a slow and insufficient denitrification in the planted float system, and thereby, planted float system had a high NH4+-N removal rate and NO3(-)-N accumulation. The presence of planted float reduced the release flux of N2O, which was 17.14 microg N x m(-2) x h(-1) for Ipomoea aquatica, 37.38 microg N x m(-2) x h(-1) for Oenanthe javanica, and 85.08 microg N x m(-2) x h(-1) for the control.