6种湿地植物吸收污水中氮和磷的动力学

为研究不同湿地植物对污染水体中氮、磷的去除效果，采用改进耗竭法研究水竹、金花菜、空心菜、雪里红、芋头和韭菜等6种湿地经济植物对溶解性总磷（TSP）、硝态氮（NO3--N）及铵态氮（NH4+-N）的吸收动力学特征。目的是在对污染水体进行修复时，可以根据不同的污染程度选择相应的经济作物。结果表明：空心菜适应任何TSP、NO3--N及NH4+-N浓度的污水，水竹则适应TSP、NO3--N及NH4+-N浓度较低的污染水体；韭菜与金花菜对TSP、NH4+-N浓度较高的污染水体有较大吸收效率，而雪里红则适合浓度较低的水体；对于含NO3--N水体，韭菜与雪里红具有较大吸收速率，适宜高NO3--N水平的养分条件，金花菜具有较大亲和力，适宜于NO3--N浓度低的污染水体；芋头的最大吸收速率最小而亲和力最大，不适宜作为湿地植物修复污染水体。6种湿地植物都具有喜铵性，对NH4+-N有更好的吸收效果。

Uptake dynamics of N and P in polluted water by 6 different wetland plants

To investigate the removal of N and P from polluted water by wetland plants, this study investigated the characteristics of the uptake dynamics of TSP, NO3--N, and NH4+-N by six types of wetland plants, Phyllostachys heteroclada Oliver, Medicago hispida Gaertn, Ipomoea aquatica Forssk, Brassica juncea var., Colocasia esculenta(L.) Schoot, and Allium tuberosum Rottler ex Spreng, using the modified depletion method. The goal was to select the proper economic aquatic plants for the remediation of polluted water with different characteristics. The results showed that I. aquatica Forssk was suitable for wastewater with a broad range of N and TSP concentrations, and P. heteroclada Oliver was best for wastewater with low N and TSP concentrations. A. tuberosum Rottler ex Spreng and M.edicago hispida Gaertn had higher absorption rates of NH4+-N and TSP, whereas A. tuberosum Rottler. ex Spreng and B. juncea var. were more suitable for NO3--N absorption. B. juncea var. was suitable for wastewater with low NH4+-N and TSP concentrations, whereas M. hispida Gaertn was fit for low NO3--N concentration wastewater remediation. C. esculenta L. had both weak affinity and a low absorption rate of N and TSP from wastewater. All six kinds of wetland plants were suitable for NH4+-N removal, as they all had good NH4+-N absorption rates.