降水和施肥对稻田地表径流总氮流失量的耦合作用  

The Coupled Effect of Precipitation and Fertilization on Nitrogen Loss Via Surface Runoff from Paddy Fields

作　　者：李建强 王鸢 陈晓冬 费冰雁 郭彬[2] 刘琛[2] 李华[2] LI Jianqiang;WANG Yuan;CHEN Xiaodong;FEI Bingyan;GUO Bin;LIU Chen;LI Hua(Pinghu Agriculture and Rural Bureau,Pinghu 314200,China;Institute of Environment Resource,Soil and Fertilizer,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021,China)

机构地区：[1]平湖市农业农村局,浙江平湖314200 [2]浙江省农业科学院环境资源与土壤肥料研究所,杭州310021

出　　处：《灌溉排水学报》2023年第10期39-45,共7页Journal of Irrigation and Drainage

基　　金：浙江省重点研发计划项目(2021C03025-01〔1〕);国家自然科学基金项目(41671300)。

摘　　要：【目的】揭示降水和施肥对稻田地表径流总氮(TN)流失量的耦合作用,为水稻种植区面源污染削减提供理论支撑。【方法】基于水稻田间试验,设置4种施肥方式,分别为常规氮肥处理(N18)、减量氮肥处理(N15)、有机肥处理(OF)和不施肥(CK),监测2019—2021年水稻生育期内的地表径流量、地表径流中的TN浓度及气象数据,分析降水和施肥对稻田地表径流TN流失量的耦合作用。【结果】2019—2021年,降水量和TN流失量呈同步下降趋势,而回归分析表明日降水量与TN流失量之间没有显著相关性,考虑降水间隔时间后所获得的分段日平均降水量与TN流失量呈正相关(回归系数≥0.36)。不同施肥处理对TN流失量的促进作用由高到低依次为:N18处理>N15处理≥OF处理>CK。结构方程模型的结果表明,分段日平均降水量、降水间隔时间、施肥量、施肥种类和降水距施肥的天数是影响TN流失量的重要因素,以上各因素的标准化总影响因子分别为0.264、-0.126、0.078、0.033和-0.038。降水相比施肥对稻田TN流失量的影响更强,且分段日平均降水量和降水间隔时间是决定地表径流TN流失量的关键因素。【结论】降水间隔时间的缩短相比降水量的增加对稻田TN流失量的促进效应更强,雨季有机肥配施相比化肥施用能够有效减少地表径流中的TN浓度,从而削减稻田TN流失量。【Objective】Nitrogen loss from soils is a pervasive environmental issue facing agricultural production in many countries.In this paper,we studied the combined effect of rainfall and fertilization on nitrogen loss via surface runoff from paddy fields in attempts to improve nitrogen management and reduce the nonpoint source pollution of rice production in Southern China.【Method】The experiment was conducted from 2019 to 2021 in a paddy field in Zhejiang province.It consisted of four nitrogen treatments:conventional nitrogen fertilization(N18),reduced nitrogen fertilization(N15),organic fertilization(OF).Without fertilization was the control.In the experiment,we measured surface runoff,total nitrogen concentration in the surface runoff.The rainfall data were obtained from a weather station on the experimental site.【Result】①Annual rainfall and annual nitrogen loss were closely correlated,but linear regression analysis showed that daily rainfall and total nitrogen did not correlate significantly.Considering the delay between rainfall and nitrogen loss vial the surface runoff can make piecewise average daily rainfall positively correlated to nitrogen loss,with the regression coefficient≥0.36.②The effect of fertilization on nitrogen loss from the runoff was ranked in the order of N18>N15>OF>CK.③Structural equation showed that,when considering the delay between rainfall and nitrogen loss,the piecewise average daily rainfall,the runoff volume,rainfall interval,the interval between rainfall and fertilization,fertilization amount,and fertilizer types were the factors affecting nitrogen loss,with their standardized total effect being 0.264,-0.126,0.078,0.033,and-0.038,respectively.The rainfall affected nitrogen loss more than the fertilization,and the piecewise average daily rainfall and rainfall interval were key factors affecting nitrogen loss.【Conclusion】For rice-wheat rotation cultivation in Zhejiang Province,a short rainfall interval affected nitrogen loss via surface runoff from paddy fields more

关 键 词：稻田 总氮流失 面源污染 施肥 降水 

分 类 号：X522[环境科学与工程—环境工程] X501