摘要
对芦苇、美人蕉、空白潜流型人工湿地中硝化、反硝化作用强度进行了对比研究.结果表明,潜流型湿地硝化作用强度受温度影响显著,且与总氮、氨氮去除率显著相关.各湿地硝化、反硝化作用强度的空间分布具有明显分层现象,湿地表层高于深层.芦苇湿地表层硝化作用强度呈中间高、两端低的变化趋势;深层则沿程递减;反硝化作用强度沿程变化不明显.垂直流湿地平均硝化作用强度高于水平流湿地;有植物湿地高于空白湿地;芦苇湿地高于美人蕉湿地.植物根系分泌物直接影响硝化作用强度,根际硝化作用强度由根面至非根区递减.潜流湿地具有较强的反硝化潜力,反硝化作用强度明显高于硝化作用强度.
To reveal the nitrogen purification mechanism in subsurface-flow constructed wetlands,nitrification and denitrification intensities were studied in reed,canna and unplanted wetlands respectively.The results show that nitrification intensity in subsurface-flow wetlands is remarkably influenced by temperature and closely correlative with total and ammonia nitrogen removal efficiency.It appears in upright direction that nitrification and enitrification intensities in upper layer are higher than that in the lower.For the reed wetland,nitrification intensity is low in both ends but high in the middle of upper layer,while it decreases gradually along distance in lower layer.The change of denitrification intensity along distance is not obvious.Average nitrification intensity is higher in vertical-flow wetland than that in horizontal-flow wetlands,higher in planted wetlands than that in unplanted wetland and higher in reed wetland than that in canna wetland.The secretion from plant roots directly results in the g
radual decrease of nitrification intensity in plant rhizosphere.Results also show that intensity of denitrification is obviously higher than that of nitrification.Thereby,subsurface-flow wetland has strong denitrification potential.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2007年第9期1965-1969,共5页
Environmental Science
基金
国家自然科学基金项目(50278016)
关键词
潜流
人工湿地
硝化/反硝化作用强度
subsurface-flow
constructed wetland
nitrification/denitrification intensity
