摘要
为了探讨微咸地下水影响下滴灌频率对土壤盐分动态过程的影响,在土柱内进行同一地下水埋深条件下的滴灌入渗试验。试验中供试地下水矿化度为3 g/L;滴灌频率设3个处理,相应的单次滴水量分别为0.5、1和2 L,滴水间隔分别为2、4和8 d;各处理的滴水总量均为2 L;以无地下水条件作为对照。试验结果表明:地下水对土壤水的补充存在两种形式,一种是地下水上升毛管水直接进入下层土壤,使土壤接近饱和状态,另一种是在地表蒸发拉动作用下,地下水上升到地表,形成稳定蒸发,并使含水率平均增加18.76个百分点,其中,滴灌频率越低(单次滴水量大),土壤出现稳定蒸发的现象越早。整个土层的盐分动态可分为两个运动方向相反的区域,即上层土壤积盐区和下层土壤脱盐区;增大滴灌频率仅能降低表层土壤的积盐程度,不能抑制上层土壤(0-30 cm土层)的积盐现象(平均积盐率为49.58%);但是下层饱和区土壤(30-60 cm土层)因地下水溶解作用使土壤脱盐(平均脱盐率为30.64%)。低频滴灌因其单次灌水量大,存在深层渗漏,能起到淋洗上层土壤盐分的作用。
To explore the influence of drip irrigation frequency on the dynamic process of soil salinity under the influence of brackish groundwater,different irrigation frequencies were treated under the same groundwater depth,and drip irrigation infiltration test was conducted in the soil column.In these experiments,the groundwater salinity was 3 g/L,3 irrigational frequencies were set with the same irrigation quantity of 2 L,the corresponding single drip irrigation quantity was 0.5,1 and 2 L,and the irrigation intervals was 2,4 and 8 days,respectively;at the same time,with no groundwater conditions as a control.The results show that there are two forms of supplementation of ground water to soil water,one is rising groundwater capillary water into the subsoil directly,bringing the soil close to the saturation state; the other is that under the action of evaporation on the surface,the groundwater rises to the surface to form a stable evaporation,increasing the moisture content by an average of 18.76 percentage points.Among them,the lower frequency of drip irrigation （a large amount of dripping water）,the earlier phenomenon of stable evaporation in the soil.The salt dynamic of the whole soil can be divided into two regions which are opposite in the direction of movement,namely,the upper layer and the lower soil desalting area; Increasing the frequency of drip irrigation can only reduce the salt level of topsoil,and can not inhibit the salt accumulation of the whole upper soil （0-30 cm soil layer） （average salt deposition rate is 49.58%）.However,the soil （30 ~ 60 cm soil layer） in the lower saturated zone （30-60 cm soil layer） desalination of soil （average desalting rate of 30.64%） due to the dissolving effect of groundwater.Low frequency drip irrigation,because of its large amount of irrigation,has deep seepage and can play the role of leaching salt in the upper soil.
作者
梁萌帆
李明思
Liang Mengfan;Li Mingsi(College of Water Conservancy and Architecture Engineering,Shihezi University,Shihezi,Xinjiang 832003,China)
出处
《石河子大学学报（自然科学版）》
CAS
北大核心
2018年第4期422-430,共9页
Journal of Shihezi University(Natural Science)
基金
国家自然科学基金(51569028)
新疆生产建设兵团软科学(2011BB039)项目
关键词
滴灌
微咸地下水
灌水频率
抑制盐分
稳定蒸发
drip irrigation
brackish groundwater
drip irrigation frequency
anti-salinization
stable evaporation
