基于水量平衡下灌区农田系统中氮素迁移及平衡的分析  

Nitrogen balance in the farmland system based on water balance in Hetao irrigation district,Inner Mongolia

作　　者：杜军[1,2] 杨培岭[1] 李云开[1] 任树梅[1] 王永忠[2] 李仙岳[1] 林艳 

机构地区：[1]中国农业大学水利与土木工程学院,北京100081 [2]宁夏农垦事业管理局,宁夏银川750001 [3]内蒙古河套总局塔布渠管理所,前旗015000

出　　处：《生态学报》2011年第16期4549-4559,共11页Acta Ecologica Sinica

基　　金：水利部公益性行业专项经费项目(200701025);长江学者和创新团队发展计划(IRT0657);中国农业大学与内蒙古农业大学科研合作基金;中国农业大学研究生科研创新专项(kycx09113)

摘　　要：以河套灌区典型灌域(前旗北疙堵乡塔布村)为研究对象,通过分析农田系统中水量平衡和氮素平衡,建立农田系统中氮素平衡和水分平衡的联立模型,并用此模型分析典型区域内农田系统中氮素随水分迁移的规律。分析表明:应用水量和氮平衡模型分析灌区农田系统中氮迁移及平衡,可以反映出农业面源污染物(氮)在整个农田系统中的去向,化肥使用量的降低和灌水量的减少,将有效的减少农田系统中氮素的输入量;秋灌—秋浇期间,玉米、番茄和葵花作物对氮的吸收率分别为17%、18%和32%,3种土壤中残留量分别为57%、60%和58%。依据河套灌区年施肥60万t计算,土壤残留量达到17.2万t。在秋灌-秋浇期间从黄河引入的氮总量达到1.21万t,随农田退水进入沟道的量为840 t。The influence of human activity on the nutrition circulation has essentially changed ecosystem processes,and chemical fertilizers and nitrogen-fixing plants further enhanced the nitrogen flux in agricultural ecosystem.When the input of nitrogen exceeds the crop assimilation capacity,surplus nitrogen in the farmland system will lead to the increase of nitrate leaching,ammonia volatilize and denitrification,and result in negative influence on the environment.The amount of absorbed N by the crop is from 26% to 36% in farmland system,and the most of the surplus N is lost by the NH3 volatilization and denitrification,and some of the surplus N leached into groundwater.Hetao irrigation district（HID） is one of the three large-scale irrigation districts in China,the fertilizers amount used in the farmland of HID is increasing during the past ten years.This paper conducted a case study on the transport and balance of nitrogen in the farmland system based on water balance in Hetao Irrigation District（HID）,Inner Mongolia.The cycle process of nitrogen and water in the farmland system was analyzed and a coupled model of the nitrogen and water balance was set up,by which the nitrogen transport rule in the farmland system was analyized. The results showed that the coupled model could reflect the relationship between water and N in farmland system by application of water-balance and N balance.The model not only reflected the migration paths of N in the farmland system,but also explained which could effectively increase the utilization of the fertilizers and which could reduce agricultural non-point pollution contribution.It could reduce the production of the agricultural non-point pollution by increasing the amount of straw returning,and it could reduce the output amount of N in farmland system by reducing the fertilizer amount. In autumn-irrigation period,the uptake rate of corn,tomato and sunflower is 17%,18% and 32% respectively,and the soil residual rate is 57%,60% and 58% respectively.In this period,the amount of N f

关 键 词：河套灌区 农田系统 氮素平衡 水量平衡 

分 类 号：S181[农业科学—农业基础科学]