摘要
以城市绿地模拟装置和暴雨径流模拟装置研究了城市绿地对实际暴雨径流污染的消减作用、机理及微生物在污染去除中的作用.城市绿地模拟装置主要由土壤、草本植被、微生物(主要吸附在土壤及植物根系上)组成,暴雨径流模拟装置包括降雨部分和径流部分,平行设置抑菌对照组.设置降雨强度为三年一遇,在降雨间隔期为14d、降雨持续时间为2h的2次降雨过程中,绿地系统对径流污染物的去除率为CODCr31.2%～41.6%,NH4+-N32.0%～47.9%,TN30.8%～38.9%,TP21.3%～38.9%.实验组和抑菌对照组对污染物的去除率在第一次降雨期间较为接近,主要的去除机制是土壤和植物根系的吸附截留作用.第二次降雨期间,实验组COD、NH4+-N、TN、TP的去除率比抑菌对照组分别提高10.2%、6.8%、4.6%和8.6%;除吸附截留作用外,微生物分解作用增强,土壤生化作用强度高于第一次降雨.降雨间隔期土壤微生物数量增加,呼吸作用增强,氮素循环活跃.由于土壤的呼吸作用和植物根系的吸收作用,土壤有机质和全氮含量降低,土壤得到再生.抑菌对照组土壤再生能力相对较差.研究结果为城市绿地系统及生态型排水系统的建设提供了指导依据.
The pollution removal from storm-water runoff by urban greenbelt,the mechanism of this process and the effect of microorganisms on pollution reduction were studied by the urban greenbelt simulator and the storm runoff simulator.The urban greenland simulator mainly consists of soil,grasses and microbes （adsorbed by soil and plant roots）.In the control experiment,streptomycin （1%） was sprayed on the soil and plant roots for microbial inhibition.The rainfall intensity in the experiment was designed as strongest in every three years,rainfall duration was two hours,and interval time between two rainfalls was 14 days.During the two rainfalls,the removal rates of CODCr,NH4^＋-N,TN and TP were 31.2%～41.6%,32%～47.9%,30.8%～38.9% and 21.3%～38.9%,respectively.During the first rainfall,the absorption and interception of pollutants by soil grains and plants roots might play an important role in pollutant removal.Therefore,the experimental group and the control group had similar pollutant removal capacity.During the second rainfall,the removal rates of CODCr,NH4^＋-N,TN and TP of the experimental group were 10.2%,6.8%,4.6% and 8.6%,repectively,which were higher than those of the control group.Besides the absorption and interception by soil grains and plants roots,microbial decomposition increased,and biochemical action intensity of soil was obviously higher than that during the first rainfall.During the rainfall interval,mineralization of organic substances,nitrification and denitrification were the major microbial activities.Therefore,the concentrations of organic substances,TN and TP in soil gradually decreased.Soil was regenerated in the experiment group,while the soil in the control experiment was not well regenerated.Fig 4,Tab 2,Ref 16
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2010年第2期240-246,共7页
Chinese Journal of Applied and Environmental Biology
基金
国家高技术研究发展计划专项基金("863"计划
No.2006AA0-6Z331)
上海市科委项目(No.2007BAK27B05)
上海市自然科学基金(No.10ZR1409900)资助~~
关键词
城市绿地
污染削减
微生物
暴雨径流
urban greenland
pollutant reduction
microorganism
storm-water runoff
作者简介
通讯作者Corresponding author（E—mail：xyli@des．ecnu．edu．cn）
