三种水(湿)生植物对浑河水体氮去除能力研究

Effect of Three Hydrophytes on Removal of Nitrogen in Hunhe River

以黄菖蒲、菖蒲和溪荪鸢尾3种常见水生植物为材料,通过室内水培试验研究了对不同程度富营养化水体中氮的去除能力。根据浑河水体富营养化状态,设置了2种处理：W0处理（低浓度）总氮15 mg/L、氨氮7.5 mg/L,W1处理（高浓度）总氮60 mg/L、氨氮30 mg/L。结果表明：3种植物对总氮氨氮都有较好的去除效果。在高低浓度组中,黄菖蒲、菖蒲和溪荪鸢尾总氮去除率分别为71.17%、95.03%,46.69%、78.31%和51.98%、80.34%;氨氮去除率分别为93.33%、69.37%,58.61%、97.33%和73.03%、84.00%。在低浓度处理中,总氮去除效果为黄菖蒲〉溪荪鸢尾〉菖蒲,氨氮去除效果为菖蒲〉溪荪鸢尾〉黄菖蒲;在高浓度处理中,总氮和氨氮去除效果均为黄菖蒲〉溪荪鸢尾〉菖蒲。黄菖蒲较适用于氮污染形式主要为氨氮且浓度较高的富营养化水体,菖蒲适用于低浓度富营养水体中的氨氮去除。浑河水体富营养化问题中氨氮浓度较高,应优先选择黄菖蒲。3种水生植物都是在前2周就已经发挥了较大的去除作用,在后2周内去除效果并不明显。黄菖蒲和溪荪鸢尾2种植物的营养去除增效均在第17~23天达到最大值。

The removal capacity of three aquatic plants ( Iris pseudacorus, Acorus calamus and Iris sanguinea) on ni-trogen was investigated through indoor hydroponic experiment .The experiments were performed under controlled conditions wherein the plants were grown in two different nutrient concentrations according to the eutrophication sta -tus of Hunhe River ( W0:TN=15 mg/L, NH4+-N=7.5 mg/L and W1∶TN=60 mg/L, NH4+-N=30 mg/L) .The results showed that three aquatic plants all displayed excellent removal capacity on total nitrogen and ammonia nitro -gen in the two treatments .The removal rates of TN in W1 and W0 were 71.17%, 95.03% by Iris pseudacorus, 46.69%, 78.31%by Acorus calamus, 51.98%, 80.34% by Iris sanguinea, respectively.Meanwhile, the re-moval rates of NH4+-N by Iris pseudacorus, Acorus calamus and Iris sanguinea were 93.33% and 69.37%, 58.61%and 97.33%, 73.03%and 84.00%, respectively.In the treatment of low concentration , the removal ef-ficiency of TN was in the order of Iris pseudacorus>Iris sanguinea>Acorus calamus, and the order of removal effi-ciency of NH4+-N was Acorus calamus>Iris sanguinea>Iris pseudacorus.While in the treatment of high concentra-tion, the removal efficiencies of TN and NH 4+-N were both in the order of Iris pseudacorus>Iris sanguinea>Acorus calamus.In general , Iris pseudacorus was suitable for the purification of eutrophic water body with high concentra-tion of NH4+-N, Acorus calamus was suitable for the purification of eutrophic water body with low concentration of NH4+-N.Therefore, Iris pseudacorus is suggested for the removal of nitrogen in Hunhe River because of the high concentration of NH 4+-N in its eutrophic water body .Removal effect of the three aquatic plants was obvious in the first two weeks and the maximum nutrient removal efficiency ( NRE) of Iris pseudacorus and Iris sanguine was ob-served from 17 d to 23 d in the experiment .