降雨、灌溉入渗和潜水蒸发在卫宁平原地下水循环中有重要的作用。为了准确评价卫宁平原地下水垂向入渗补给量和蒸发量，通过设立中卫、中宁两个包气带原位试验点，观测期为2013年6月~2013年11月和2014年4月~2014年10月，获取了两个试验点不同埋深处的土壤水负压、温度、岩性及水分运移参数，并采用定位通量法计算试验点的地表蒸散发、入渗量和潜水面蒸发、入渗量。结果显示：在包气带岩性相同、灌溉期相同（7~10月）、总灌溉量相近条件下，作物的灌溉模式决定了灌溉对潜水的补给强度：玉米少次大量（150 mm·次-1）灌溉对潜水的补给量为373.65 mm，远远大于茄子多次小量（50 mm·次-1）的灌溉模式下的152.3 mm；而在包气带岩性相同、种植作物相同、灌溉模式不变的前提下，同时期潜水面净补给强度相近：中宁试验点2013年7~10月份潜水面净通量为32.88 mm，2014年同期为57.42 mm。在降雨情况或灌溉量较小（50 mm）的情况下，植被的生长会阻碍水分在包气带中的下渗；在灌溉量较大（100 mm和150 mm）的情况下，植被的生长会促进包气带水分的下渗。
Moisture migration including precipitation,irrigation infiltration and evaporation from phreatic water in vadose zone plays an important role in groundwater circulation.In order to accurately evaluate the water exchange quantity through the vadose zone in Weining Plain,two in situ experiment sites were set in Zhongwei County and Zhongning County,Ningxia Hui Autonomous Region,China in this study.The observation was conducted from Jun 2013 to Nov 2013 and from Apr 2014 to Oct 2014 respectively.The soil water pressure,soil temperature,soil texture and soil hydraulic parameters at different depths were measured.The evapotranspiration,infiltration at the land surface and the evaporation,infiltration on the groundwater table were calculated using the oriented flux method.At Zhongwei experiment site,the groundwater recharge through the vadose zone in maize land which was 373.65 mm is much greater than that in eggplant land which was 152.3 mm,with the irrigation pattern in maize land being low frequency with large amount of water each time (150 mm),and the irrigation pattern in the eggplant land being high frequency with small amount of water each time (50 mm).It indicates that under the condition of the same soil texture,the same irrigation period (July to October) and the similar total irrigation amount,the irrigation pattern of crops determines the recharge quantity to the phreatic water.At Zhongning experiment site,the groundwater net recharge through the vadose zone was 32.88 mm from Jul to Oct in 2013 and 57.42 mm during the same period in 2014.It indicates that under the condition of the same soil texture,the same crop,and the same irrigation pattern,the change of the groundwater net recharge through the vadose zone is little.Under the rainfall or small amount of flooding irrigation (50 mm）the vegetation in growth will hinder the water from being infiltrated into the vadose zone,but it accelerates the infiltration of water in the case of large irrigation volume (100-150 mm）.
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