摘要
生态沟渠是我国南方水网区农业面源污染防控技术体系的重要环节,其与农田面积相对应的配置规模研究尚无定论。选择3条规格相同的试验沟渠进行生态化改造,增设湿生植物、生物填料箱和生态滤坝,构建生态沟渠。设置不同强化净化措施的沟渠处理,分别为:湿生植物+1座生物填料箱+1座生态滤坝处理(D1)、湿生植物+2座生物填料箱+2座生态滤坝处理(D2)、湿生植物+3座生物填料箱+3座生态滤坝处理(D3),并控制进水流量的变化,对比不同处理生态沟渠对农田退水污染物的净化效能,分析污染通量在时空尺度上的变化情况,探讨对应于单位农田面积的生态沟渠配置规模。结果表明:强化处理生态沟渠对TN、NH_(4)^(+)-N、TP和COD的削减率分别为33.9%~49.1%、37.8%~42.9%、29.3%~42.0%和60.0%~78.1%,其中,D2和D3对TN和TP的削减率较高。D2和D3出水TN和COD的污染通量显著低于D1(P<0.05),而3条沟渠出水NH_(4)^(+)-N和TP的污染通量之间无显著差异。流水试验条件下,出水TN和TP降低至2.0 mg·L^(-1)和0.2 mg·L^(-1),D3所需要的沟渠长度分别为85.4 m和57.3 m,为3条强化措施处理沟渠中最短;对应于667 m2农田,单日降雨量为60 mm,TN浓度降低4.64 mg·L^(-1),按照D3沟渠的设施配置,1 m^(3)的生态沟渠可处理19 m^(2)的农田退水。在后续研究中,可因地制宜应用湿生植物+3座生物填料箱+3座生态滤坝(D3)的强化净化措施,并有效衔接生态沟渠与汇水塘浜,考量两者的综合净化效能,对“田-沟-塘-浜”的配置规模进行总体测算。
Ecological ditch is an important part of control technology system of agricultural non-point source pollution in south China water network area.The appropriate scale of ecological ditch corresponding to farmland area has not been determined yet.3 ditches of the same specification have been reconstructed to ecological ditches by setting up wet plants,biofilm carrier boxes and ecological filter dams.The 3 ecological ditch treatments with different enhanced purification measures were set up,including the treatment of wet plants,one biofilm carrier box with one ecological filter dams(D1);the treatment of wet plants,two biofilm carrier boxes with two ecological filter dams(D2);the treatment of wet plants,three biofilm carrier boxes with three ecological filter dams(D3).Meanwhile,the influent flows of the ditches were controlled.Purification efficiencies of different treatment ecological ditches on pollutants from farmland runoff were compared,the variations of pollution flux on the time and space scale were analyzed,and the appropriate scale of ecological ditch corresponding to unit farmland area were discussed.The results showed the removal efficiencies of TN,NH_(4)^(+)-N,TP and COD in the ecological ditches were respectively 33.9%-49.1%,37.8%-42.9%,29.3%-42.0% and 60.0%-78.1%,meanwhile the removal efficiencies of TN and TP in D2 and D3 were higher.The pollutant fluxes of TN and COD in the effluent of D2 and D3 were significantly lower than D1,while there was no significant difference among the pollutant fluxes of NH_(4)^(+)-N and TP in the effluent of the 3 ecological ditches.The average TN and TP concentrations was reduced down to 2 mg·L^(-1) and 0.2 mg·L^(-1) at the point of 85.4 m and 57.3 m along the ditch of D3,respectively.Moreover,the required length of D3 was the shortest one among the 3 ecological ditches.Under the flow experiment conditions with daily rainfall of 60 mm·d^(-1) and TN concentration reduction of 4.64 mg·L^(-1),1 m^(3) ecological ditch with the configuration facilities of D3 can treat the drainage from 19 m^(2) farmland.In follow-up studies,the enhanced purification measures of wet plants,three biofilm carrier boxes with three ecological filter dams(D3)should be applied according to local conditions,and the ecological ditches and catchment ponds and branches should be effectively combined,comprehensive purification efficiency of ecological ditches and catchment ponds and branches should be considered to estimate the configuration scale of“farmlands-ditches-ponds-rivers”as a whole.
作者
张迎颖
李敏
潘吴意
王岩
姜智绘
苏国东
刘海琴
张志勇
ZHANG Yingying;LI Min;PAN Wuyi;WANG Yan;JIANG Zhihui;SU Guodong;LIU Haiqin;ZHANG Zhiyong(Institute of Agricultural Resources and Environmental Sciences,Jiangsu Academy of Agricultural Sciences/Key Laboratory of Agro-Environment in Downstream of Yangtze Plain,Ministry of Agriculture and Rural Affairs,Nanjing 210014,China;School of the Environment and Safety Engineering,Jiangsu University,Zhenjiang 212013,China;Institute of Leisure Agriculture,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China)
出处
《农业环境科学学报》
北大核心
2025年第1期105-116,共12页
Journal of Agro-Environment Science
基金
国家重点研发计划项目(2021YFD1700805-02)
江苏省重点研发计划项目(D21YFD17008)
江苏省农业科技自主创新资金项目(CX(19)1007)
国家重大科技专项水体污染控制与治理专项(2017ZX07202004-07)。
关键词
生态沟渠
农田退水
氮
磷
配置规模
ecological ditch
farmland runoff
nitrogen
phosphorus
configuration scale
