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针对阴山北麓旱作区雨水蓄积利用效率低的问题,探讨本地区主要种植方式对降水的蓄积效应及降水后土壤水分变化动态。本研究采用模拟降水试验方法,对降水后农田土层水分含量的变化情况进行监测和分析,结果表明:1)在4mm降水下,粘壤土不同处理土壤贮水量显著高于对照;在12mm降水下,沙壤土不同处理土壤贮水量显著高于对照。不同降雨量粘壤土和沙壤土贮水量增量表现一致,大小顺序均为垄作全膜>垄作半膜>平作全膜>平作半膜>平作(CK)。以8mm降水为例,粘壤土各处理中,垄作全膜处理下土壤贮水增量为6.5mm,是对照的1.76倍,沙壤土各处理中,垄作全膜种植方式贮水增量是对照的3.2倍。2)垄作全膜能够将12mm以上降水蓄积在粘壤土表层,使该层土壤水分变化较小,土壤含水量基本维持在15.0%~16.5%,沙壤土蓄积雨水效果较差。3)在降水后5d内,粘壤土土壤水分变化为0~20cm土壤含水量呈降低趋势,降水后第3天该土层土壤含水量下降变缓,20~30cm土壤含水量先增加后降低,在降水后第3天达到最高,30~50cm土壤含水量均呈增加趋势;沙壤土土壤水分变化为0~30cm土壤含水量下降趋势较明显,30~50cm土壤含水量表现为先增加后降低。因此,在本地区生产条件下,垄作全膜不仅具有良好的集雨效果,而且能够将积蓄雨水主要分布于土壤表层30~50cm,从而对有限的降水资源进行再分配,提高作物的水分利用效率。
Aiming at the problem of low efficiency of rainwater accumulation and utilization in the rainfed area at the northern foot of Yinshan Mountain, the accumulation effect of main planting patterns on precipitation and the dynamic change of soil moisture after precipitation were discussed. In this study, simulated rainfall test method was used to monitor and analyze the changes of soil moisture content after the precipitation. The results showed that: 1) under 4 mm rainfall, the soil water storage capacity of clay soil was significantly higher than that of the control; The soil water storage capacity of sandy loam soil was significantly higher than that of the control. The accumulative water storage capacity of clay loam soil and sandy loam increased with different rainfalls in the same order. Taking 8mm precipitation as an example, in the treatment of clay loam, the increment of soil water storage was 6.5mm, which was 1.76 times of that of the control. Under the treatment of sandy loam soil, Times 2) The whole film of the ridge can accumulate more than 12mm of precipitation on the surface of clay loam so that the change of soil moisture in this layer is small, the soil water content basically maintains at 15.0% ~ 16.5%, and the accumulation of rainwater in sandy loam is less effective. 3) Within 5 days after rainfall, the soil water content of clay soil changed from 0 to 20 cm. The soil water content of clay soil decreased slowly on the 3rd day after rainfall. Soil water content of 20-30 cm increased firstly and then decreased, Reaching the maximum on the third day after precipitation and the soil water content in 30-50 cm increased. The soil water content in sandy loam soil decreased from 0 to 30 cm, and the soil water content in 30-50 cm soil increased first and then decreased. Therefore, under the conditions of the local production, the whole film of ridge planting not only has a good rainwater harvesting effect, but also can distribute the accumulated rainwater mainly in the surface layer of 30-50 cm so as to redistribute the limited rainfall resources and improve the water use efficiency .