稻麦轮作高标准农田控制排水对排水与氮素输出削减效果模拟  

Simulation of Effect of Controlled Drainage on Reducing Drainage and Nitrogen Output from High Standard Farmland in Rice and Wheat Rotation Area

作　　者：罗纨[1] 王嘉诚 贾忠华[1] 刘文龙 卫同辉 邹家荣 朱梦妍 吴慧 彭佳雯 LUO Wan;WANG Jiacheng;JIA Zhonghua;LIU Wenlong;WEI Tonghui;ZOU Jiarong;ZHU Mengyan;WU Hui;PENG Jiawen(College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou 225009,China)

机构地区：[1]扬州大学水利科学与工程学院,扬州225009

出　　处：《农业机械学报》2024年第4期272-279,311,共9页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(52379050、51979239)。

摘　　要：稻麦轮作区高标准农田建设中,通过加深排水沟提高麦作期农田排水降渍能力的同时,加大稻作期农田排水输出,不仅降低了水资源利用效率,而且加重了接纳水体的污染。本文基于江苏省扬州市沿运灌区稻麦轮作农田排水水文水质过程的监测结果,利用田间水文模型(DRAINMOD)模拟了长序列气象条件下,灌区提高农田降渍能力对稻田排水、氮素流失及灌溉需求的负面影响以及控制排水措施的积极效果。结果表明,在节水灌溉模式下,研究区排水沟深度由现状的60 cm加深至120 cm,排水间距由120 m加密至20 m时,稻作期排水量与总氮(TN)输出负荷增加9.0%~22.2%、氨氮(NH_(3)-N)输出负荷增加4.0%~16.8%、灌溉用水量增加9.6%~23.4%。若结合田间管理要求,实施控制排水则可有效缓解提高农田降渍能力造成的负面影响;当排水沟深为120 cm,间距为120~20 m时,稻作期控制排水可使排水量和TN输出负荷减少19.3%~35.3%、NH_(3)-N输出负荷减少7.6%~27.2%、灌溉用水量减少22.9%~40.0%。由于控制排水降低了地下排水梯度,相较于传统排水,农沟从60 cm加深至120 cm时,地下排水平均占比降至50.7%,灌溉用水量相应减少。综上,稻麦轮作农田控制排水具有显著的节水减排作用,可有效降低高标准农田建设中提高降渍能力所产生的负面影响。研究成果可为稻麦轮作区高标准农田建设与水环境保护提供理论依据与技术支撑。In the high standard farmland construction in the plain river network areas,improving field drainage capacity for waterlogging reduction may increase drainage and the associated pollutants discharge to the receiving water bodies.So it is necessary to take controlled drainage(CD) measures to mitigate the adverse impact of crop production on the ecological environment.Based on a monitoring study on drainage and water quality processes conducted in the rice and wheat rotation fields in the Yanyun Irrigation District of Yangzhou,Jiangsu Province from 2021 to 2022,an analytical study by using the field hydrological model—DRAINMOD was presented to examine the impact of increasing drainage intensity and controlled drainage(CD) on rice field drainage,nitrogen losses,and irrigation demands based on long-term meteorological records.The simulation results showed that under the traditional drainage(TD) conditions,when the drainage spacing(L) was between 120 m and 20 m and the depth(D) was increased from 60 cm to 120 cm,the predicted drainage and total nitrogen(TN) losses were increased by 9.0%~22.2%,the ammonia nitrogen(NH_3-N) loss was increased by 4.0%~16.8%,and the irrigation demand was increased by 9.6%~23.4%.The increases in drainage,irrigation,and nitrogen losses were more pronounced when the drainage intensity was high.Considering the differences in drainage requirements during different periods of rice and wheat rotation,the aforementioned negative effects can be avoided with controlled drainage measures.Under the controlled drainage conditions,when the drainage spacing(L) was at 120~20 m and the depth was at 60 cm,the predicted drainage and TN losses were decreased by 12.0%~22.9%,NH_3-N loss was decreased by 3.4%~22.0%,and irrigation demand was decreased by 14.6%~28.5%.When the drainage depth was at 120 cm,the predicted drainage and TN losses were decreased by 19.3%~35.3%,NH_3-N loss was decreased by 7.6%~27.2%,and irrigation demand was decreased by 22.9%~40.0%.For smaller drainage spacing,the water-saving and nit

关 键 词：控制排水 氮素 灌溉 高标准农田 DRAINMOD模型 稻麦轮作农田 

分 类 号：S276.3[农业科学—农业水土工程]