人工湿地污水处理系统中的植物氮磷吸收富集能力研究

Nitrogen and phosphorus removal capacity of plant species in constructed wetlands for treating municipal wastewater

比较研究了人工湿地污水处理系统中7种植物对氮、磷的吸收能力。研究表明，所选7种湿地植物，稳定生长4个月后，平均总生物量在1215～3500g／m^2，植物氮、磷平均质量浓度分别为13．76-23．11、1．44～3．80mg／g。香蒲具有最高氮积累量达48．18g／m^2，梭鱼草具有最高磷积累量为7．23g／m^2，姜草对氮、磷的积累量最低分别为21．40、1．68g／m^2。植物地上部氮、磷积累量与地下部的氮、磷积累量差异较大，除姜草外，植物地上部、地下部的氮、磷积累量比均大于3，黄花美人蕉地上部、地下部的氮、磷积累量比分别达11．75、12．10。通过植物收割去除氮、磷量约占湿地总去除量的2％～6％。

The nitrogen and phosphorus removal capacity of seven plant species （Canna indica L. ,Canna indica vat. flava , T ypha augusti folia , Pennisetum purpureum Schumach , Colocasiaesculenta , Pontedena cordata and Cymbopogon martini） was compared in the constructed wetlands established for treating municipal wastewater. After 4 months of growth, the total biomass, nitrogen and phosphorus contents of the plants were found in the range 1 215- 3 500 g/m^2 , 13.76-23.11 mg/g and 1.44-3.80 mg/g, respectively. The nitrogen uptake of the plants ranged from 21.40 g/mz to 48, 18 g/mz and that phosphorus uptake from 1.68 g/m^2 to 7.23 g/m^2 ; Typha augustifolia and Pontedena cordata exhibited the highest uptake of N and P respectively, while Cymbopogon martini exhibited the least uptake of both N and P. The above ground tissues accumulated much more N and P than the below ground tissues; the ratio was〉3, except for Cymbopogon martini（〉2）, while the highest ratios of 11.75 for N and 12.10 for P were found in Canna indica vat. flava. The total plant uptake of nitrogen and phosphorus accounted for 2% to 6% of the overall nutrient removal in the wetland wastewater treatment system.