旱作物降渍标准分期设置及其对农田水分影响研究OA

Aiming at the management needs of farmland subsurface waterlogging damage,this study divided the growth cycle of upland field crops into seedling stage,vegetative development stage and maturity stage according to the differences in vertical distribution of root systems at different growth stages,and proposed growth-stage-specific water table control criteria for subsurface waterlogging mitigation,which is implemented through water level regulation of drainage ditches.A field water balance simulation model was established to simulate the variations of irrigation and drainage under the proposed criteria in different hydrological years.The results showed that the actual irrigation volume was reduced by 100%,64.2%,61.8%and 23.1%in wet year,normal flow year,moderate drought year and severe drought year,respectively,with the total drainage volume cut by 2%to 4%.Validated by field plot experiments,the model presented a relative error of less than 5%.This study demonstrates that the technology of growth-stage-specific setting of waterlogging mitigation criteria is technically feasible with integrated benefits of water conservation and drainage reduction,and can provide technical support for the prevention and mitigation of farmland surface and subsurface waterlogging,as well as the efficient utilization of agricultural water resources.