雨强及播栽方式对太湖地区麦田径流氮磷流失的影响  

Effects of Rainfall Intensity and Sowing Method on Nitrogen and Phosphorus Losses by Surface Runoff from Wheat Field in Taihu Lake Region

作　　者：严磊 吴田乡 赵素雅 薛利红[1] 侯朋福[1] 徐德福[2] 杨林章[1] YAN Lei;WU Tianxiang;ZHAO Suya;XUE Lihong;HOU Pengfu;XU Defu;YANG Linzhang(Key Lab of Agro-environment in Downstream of Yangtze Plain,Ministry of Agriculture and Rural Affairs,Institute of Agricultural Resources and Environment,Jiangsu Academy of Agricultural Sciences,Nanjing 210014,China;School of Environmental Science and Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China;Jiangsu Station for Protection of Arable Land Quality and Agricultural Environment,Nanjing 210036,China)

机构地区：[1]江苏省农业科学院农业资源与环境研究所/农业农村部长江下游平原农业环境重点实验室,南京210014 [2]南京信息工程大学环境科学与工程学院,南京210044 [3]江苏省耕地质量与农业环境保护站,南京210036

出　　处：《土壤》2022年第2期358-364,共7页Soils

基　　金：国家重点研发计划项目(2021YFD1700800);江苏省农业科技自主创新资金项目(CX19(1007))资助。

摘　　要：为明确太湖地区麦田氮磷流失特征,通过田间模拟试验研究了播栽方式(条播、撒播)和降雨强度(低,30 mm/h;中,60 mm/h;高,90 mm/h)对麦田氮磷流失的影响。结果表明:初始产流时间与雨强显著负相关,而径流系数与雨强显著正相关(P<0.01)。径流氮磷浓度在径流初期较高,并随产流时间不断降低,且均可用对数函数描述。氮磷流失率随产流时间呈“先升后降”的变化趋势,中后期流失率最大。除中雨强下条播处理的氮素流失率最高外,氮磷流失峰值浓度和流失率均随雨强增大而增加。受径流系数和流失率影响,除中雨强下条播处理的氮素流失量最高外,两种播栽方式下氮磷流失量均随雨强增大而显著增加。氮素流失以NO^(–)_(x)-N为主(40%~62%),磷素流失以颗粒态磷为主(50%~71%)。另外,等雨强下条播处理的径流系数和氮磷流失量高于撒播处理。综上,降雨驱动的氮磷流失具有典型阶段特征,径流初期的氮磷浓度较高而中后期流失率较大,且条播麦田对雨强的响应更加强烈。To clarify the properties of N and P losses in Taihu lake region,the effects of sowing method(PR,plant in rows;BS,broadcast sowing)and rainfall intensity(SI,30 mm/h;MI,60 mm/h;LI,90 mm/h)on N and P losses from wheat field were investigated by field simulation trial.The results showed that“initial runoff time”was negatively correlated with rainfall intensity while runoff coefficient positively correlated with rainfall intensity(P<0.01).N and P loss concentrations peaked at the initial stage and decreased over time following a logarithmic-function relationship.The loss rates of N and P showed a trend of"rising and then falling"with runoff time,and were greatest during middle to late period.The peak concentrations and rates of N and P losses increased with rainfall intensity except for N loss rate was the highest under MI in PR trials.Affected by runoff coefficient and nutrient loss rate,N and P loss amounts were significantly increased with rainfall intensity except for N loss was the highest under MI in PR treatments.NO^(-)_(x)-N(40%–62%)and particulate phosphorus(50%–71%)were the main forms of N and P losses respectively.Also,the runoff coefficient and nutrient loss rate were higher in PR treatment than those in BS treatment under the same rainfall intensity.The results suggest that rainfall-driven N and P losses have typical phase characteristics.N and P concentrations peak during the initial runoff period,while N and P loss rates are the highest during the middle-late phase.The runoff from wheat field with PR mode is more likely to be affected by rainfall intensity.

关 键 词：面源污染 旱地 地表径流 氮磷流失 

分 类 号：S157[农业科学—土壤学]