基于DRAINMOD的长江下游平原农田排水条件对大豆产量影响的模拟

Simulation of the effect of farmland drainage conditions on soybean yield in the lower Yangtze River Plain based on DRAINMOD

为探讨改善农田排水条件对大豆产量的影响,结合大豆耐渍试验结果,考虑当前高标准农田建设要求,运用DRAINMOD田间水文模型模拟不同排水条件下农田降渍效果及大豆产量的变化规律。研究结果表明:DRAINMOD模型可准确预测研究区农田地下水位动态变化和作物产量;仅改善农田地表排水状况对农田降渍及提高大豆产量的作用有限,通过暗管排水提高地下排水强度,可有效降低农田渍害的发生率,保证大豆因渍害减产的几率低于10%;研究区大豆田除涝降渍的暗管排水系统最优布局为间距15~20m、埋深1.0~1.1m。研究成果可为研究区及类似地区高标准农田暗管排水系统建设及大豆高产稳产提供参考。

In order to explore the effect of improving drainage conditions on soybean yield,combined with the results of soybean waterlogging tolerance experiment and considering current high-standard farmland construction requirements,DRAINMOD field hydrological model is used to simulate the effect of farmland waterlogging control and the change law of soybean yield under different drainage conditions.The results show that the DRAINMOD model can accurately predict the dynamics of farmland groundwater table and crop yield in the study area.Improving the farmland surface drainage has only limited effect on reducing waterlogging and increasing soybean yield.By increasing the intensity of subsurface drainage through tile drainage,the occurrence of farmland waterlogging can be effectively reduced and the yield reduction rate of soybean due to waterlogging can be less than 10%.The optimal layout for tile drainage system to meet the requirements of waterlogging reduction in soybean fields in the study area is 15~20 m spacing and 1.0~1.1 m burial depth.The research results can provide reference for the construction of high-standard farmland drainage system and soybean high and stable yield in the study area and similar areas.