膜下滴灌条件下沟垄规格对水分运移过程影响研究

Impact of Furrow and Ridge Size on Water Transport Under Drip Irrigation Under Film

沟垄栽培措施为重要的农艺耕作方式,研究膜下滴灌条件下沟垄规格对土壤水分运移的影响有利于提高水分利用效率。通过室内土箱模拟试验,探究了沟底宽度等沟垄规格参数对土壤湿润体的形状及水分分布的影响,采用多元线性回归方程构建了湿润锋运移距离模型,模拟了试验工况下土壤水分输运过程,并验证了模型的预测效果,最后基于构建的运移距离模型确定了试验工况下3 a生枸杞栽培种植最优沟垄规格。研究结果表明:随着沟底宽度的增加,湿润体形状愈发扁平,湿润体中水分分布重心会随沟底宽度的增加而逐渐上移;土壤含水率等值线分布图与湿润体形状图大致相似,呈由密至疏分布格局;构建的湿润锋运移距离模型预测的水分运移距离与试验结果误差较小,模型精度较高;试验工况下,采用膜下滴灌技术的3 a生枸杞栽培种植最优沟底宽度为22.50~28.90 cm。

Ridge and furrow cultivation as an important agronomic cultivation method,the research on the influence of furrow and ridge size on soil water transport under point source drip irrigation under film is conducive to improving water use efficiency.In this paper,the influence of furrow and ridge size parameters,such as furrow width,on the shape characteristics and water distribution of soil wetted body was explored through indoor soil tank simulation experiment.The model of transport distance of wetted body was established by multiple linear regression equation,the process of water transport under experimental conditions was simulated,and the predictive effect of the model was verified.Fi⁃nally,the optimal furrow size for 3⁃year⁃old Chinese wolfberry planting under experimental conditions was determined based on the estab⁃lished transport distance model.The results show that with the increase of ditch bottom width,the shape of wetted body becomes flatter and the center of gravity of water distribution in wetted body will gradually move up with the increase of ditch bottom width.The contour distribu⁃tion map of soil water content is similar to that of wetted body,showing a pattern from dense to sparse.The predicted water transport distance by the constructed wetted body transport distance model has little error with the experimental results,and the model has high precision.Under the experimental conditions,the optimum ditch bottom width for 3⁃year⁃old Lycium barbarbarum cultivated under film drip irrigation technolo⁃gy ranges from 22.50 cm to 28.90 cm.