摘要
为探究在限制入渗域条件下的土壤水时空变异性特征,在土箱中模拟根域限制栽培的立地条件,分析不同滴头流量的点源入渗土壤水的时空分布及湿润体变化过程,建立不同流量湿润锋运移距离与时间之间的数学关系。试验结果表明:限制入渗域条件下试验前后湿润体形状变化明显;限制入渗域能够有效降低水分下渗速率,阻止无效扩散,减少灌溉水的深层渗漏。与常规条件相比,限制入渗域处理使土壤水下渗速率降低了2.30%~40.38%;当灌水量相同,灌水速率不同时,在灌溉后期,3 L/h的滴头流量既能减少土表水分蒸发,也能使湿润峰达到土壤深层,但是相比3 L/h的滴头流量,4 L/h的滴头流量能减少水分深层渗漏。进一步验证了根域限制栽培技术在节水方面的合理性,相关结果能够为根域限制栽培作物的滴灌滴头流量选取提供一定参考。
In order to study the spatiotemporal characteristics of soil moisture under restricted infiltration area condition,the indoor soil box simulation experiment method is chosen to establish mathematical relationship between wetting front migration and time under different drip irrigation flow rates,and then variational process of wetted soil is analyzed.The results show that restricted infiltration area condition has significant effect on the shape of wetted soil.The restricted infiltration area condition can effectively reduce the infiltration rate of soil water,prevent ineffective diffusion and reduce the deep leakage of irrigation water.Compared with the normal condition,the restricted infiltration area condition can reduce the water infiltration rate by 2.30%to 40.38%.With the same irrigation amount and different irrigation rates,3 L/h flow rate not only reduces the evaporation of soil surface water,but also makes wetting front reach the deep layer of soil at the later stage of irrigation.While compared with 3 L/h flow rate,4 L/h flow rate reduces the deep leakage of irrigation water.This study further verifies the rationality of water-saving with cultivation technology of restricted root volume.The results can provide some references for the selection of drip irrigation flow rate of crops cultivation technology of restricted root volume.
作者
宁莎莎
徐利岗
张林
王怀博
NING Sha-sha;XU Li-gang;ZHANG Lin;WANG Huai-bo(College of Water Resources and Architectural Engineering of China,Northwest A&F University,Xianyang 712100,Shaanxi Province,China;The Scientific Research Institute of the Water Conservancy of Ningxia,Yinchuan 750021,China;Institute of Soil and Water Conservation,Northwest A&F University,Xianyang 712100,Shaanxi Province,China)
出处
《节水灌溉》
北大核心
2021年第3期51-57,共7页
Water Saving Irrigation
基金
宁夏重点研发计划项目(2018BBF02015,2020BFH02014)
宁夏领军人才项目(KJT2016005)。
关键词
根域限制栽培
滴灌
湿润峰运移
土壤含水率
cultivation technology of restricted root volume
drip irrigation
wet front migration
soil moisture content
