不同水深条件下芦苇湿地对氮磷的去除研究

研究了两种水深条件(2cm浅水位和15cm深水位)下芦苇湿地对模拟太湖水中氮磷的净化能力。结果表明,芦苇的存在明显地促进湿地脱氮除磷能力的发挥。湿地内反硝化过程为主要脱氮途径。芦苇对湿地反硝化过程的促进作用主要是通过提供有机碳源实现的。在相同进水水质和停留时间为24h的运行条件下,浅水位芦苇湿地与深水位芦苇湿地相比对氮磷的去除率更高,但后者对氮磷的去除速度更快。

Removal of Nitrogen and Phosphorus by Reed Wetland under Different Hydrologic Conditions

Purification of nitrogen and phosphorus by reed wetland under two different water levels including 2cm and 15cm from aqueous solution simulating Taihu Lake water was investigated.Results showed that compared with control without macrophytes,reed plant significantly improved the removal performance of wetland for both nitrogen and phosphorus under each water level.Denitrification was the most important mechanism for nitrogen removal.Enhancement in denitrification by reed plant was due mainly to the supply of litter and root exudates which served as organic carbon source for denitrifying bacteria.Under the same nutrients concentration and retention time,wetland with shallow water level had higher removal efficiency than that with deep water level,while higher amount per unit area per day of nutrients was removed by the latter.