3种典型水生植物对富营养化水体氮磷的去除效果分析

目的]分析3种典型水生植物对富营养化水体N、P的去除效果。方法]以挺水植物菖蒲、浮叶植物大聚草和沉水植物金鱼藻为研究对象,通过室内静态培养,探讨3种典型水生植物对富营养化水体中N、P的去除效果。结果]3种水生植物DHN的去除率均超过95.00%;对TN的去除率在70.00%左右;金鱼藻对PO43--P的去除率较高,为85.71%;而菖蒲对TP的去除率最大,高达90.45%。3种水生植物TN浓度均呈现先升高后降低的规律,且在降低过程中又呈现先快后缓的趋势;金鱼藻和大聚草DHN浓度表现为初期迅速降低,呈短暂稳定的状态后又降低,而菖蒲DHN呈持续降低的趋势;菖蒲的PO43--P在试验初期呈短暂升高趋势后持续降低,而大聚草和金鱼藻的PO43--P在逐渐降低的过程中呈升高或稳定的状态;菖蒲的TP在试验初期升高到1.78 mg/L后持续降低,金鱼藻和大聚草的TP在整个试验过程中则呈缓慢降低的趋势。结论]3种水生植物TN和TP浓度随时间推移呈y=ae-bx(a0,b0)的变化,其中,挺水植物菖蒲的N、P去除能力较强。

Analysis on Removal Effects of the Three Typical Aquatic Plants on N and P in Eutrophic Water

Objective] The research aimed to analyze removal effects of the three typical aquatic plants on N and P in eutrophic water.Method] Based on static test,three typical kinds of aquatic plants as objects,including emerging plants like Acorus calamus,floating plants like Poly grass and submerged plants like Ceratophyllum were used to study their removal effects on N and P in eutrophic water.Result] Removal efficiencies of the three typical aquatic plants for ammonia nitrogen(DHN) were all in excess of 95.00%,while removal efficiencies for total nitrogen(TN) were about 70.00%.The removal efficiency of Ceratophyllum for phosphate phosphorus(PO43——P) was 85.71%,while removal efficiency of Acorus calamus for total phosphorus(TP) was 90.45%.TN contents of the three typical aquatic plants all presented change rules of increasing firstly declining then,and the declining trend was described as "fast,then slow".DHN contents of Poly grass and Ceratophyllum exhibited a rapid initial decline and then decreased slowly after a short stability,while DHN content of Acorus calamus decreased continuously.Besides,PO43——P content of Acorus calamus increased firstly and then decreased continuously,while PO43——P contents of Poly grass and Ceratophyllum presented increasing or stable trend in the gradual declining process.TP content of Acorus calamus increased to 1.78 mg/L and then decreased continuously,while TP contents of Poly grass and Ceratophyllum showed a slow decrease.Conclusion] TN and TP contents of the three typical aquatic plants all showed negative exponent relationships with time:y=ae-bx(a>0,b>0).Removal ability of emerging plants like Acorus calamus to N and P was stronger than that of the other two aquatic plants.