不同湿地植物对污水中氮磷去除的贡献

Different wetland plant roles of removing nitrogen and phosphorus on sewage water

选择5种湿地植物(芦苇、东方香蒲、菖蒲、茭白、鸢尾)和1种喜湿灌木(蒿柳),研究重度富营养化水体中植物的生长特性和氮磷去除效果.研究发现,所选用的6种植物在实验池中均生长良好,稳定生长105d以后,各种植物的总生物量在424-1772g/m2之间,除了香蒲的地上地下生物量比(A/U)达到3.23外,其它的比值在0.63-1.49之间.6种植物地上部N和P浓度分别在13.12-28.83mg/g及1.55-3.77mg/g之间,地下部N和P浓度在7.76-15.60mg/g及1.70-2.71mg/g之间,大部分植物地上部N和P的浓度大于地下部.6种植物平均氮、磷积累量分别为20.60g/m2和3.08g/m2,其中地上部平均氮、磷积累量分别占66.60%和58.22%.不同植物筛选池对不同污染物的净化效果有差异,鸢尾池对TN的净化效果最好,芦苇池对TP的净化效果最好.植物的氮、磷积累量与浓度及生物量之间均存在显著相关.

Five kinds of wetland plants,including reed（Phragmites australis）,oriental cattail（Typha orientalis）,calamus（Zizania aquatica）,wildrice stem（Acorus calamus）,Iris（Iris tenuifolia）,and one kind of shrub of willow（Salix viminalis） were selected to study the growth characteristics of plants and the role of removing nitrogen and phosphorus in severe eutrophic waters.The study showed that the six kinds of plants in experiments grew well and steadily.After 105 days,the total biomass ranged from 424 to 1772g/m2.Ratios of most plant biomass above/below ground（A/U） varied between 0.63 and 1.49,except for oriental cattail（A/U： 3.23）.Concentrations of nitrogen and phosphorus in the biomass of above ground ranged from 13.12 to 28.83mg/g and from 1.55 to 3.77mg/g,respectively.Concentrations of nitrogen and phosphorus in the biomass below ground ranged from 7.76 to 15.60mg/g and from 1.70 to 2.71mg/g,respectively.The concentrations of nitrogen and phosphorus between above and below ground biomass differed significantly.The average plant accumulations of nitrogen and phosphorus were 20.60g/m2 and 3.08g/m2,which the above ground accounted for 66.60% and 58.22%,respectively.Purification effect of the plants on different pollutants was different.The best purification effects for TN in Iris and TP in reed were found.Plant accumulations of nitrogen and phosphorus displayed significantly positive linear correlation with plant biomass and concentrations of nitrogen and phosphorus.