半干旱区滴头流量对土壤水分变化影响的研究

Research on Effect of Different Dripper Discharges on Soil Moisture in Semi-arid Region

缺水问题严重制约了我国北方干旱半干旱地区作物的产量,交替滴灌是一种有效的节水灌水方式,而不同的土壤质地与气候条件应选择不同的滴头流量。本文研究了干旱区不同的滴头流量下土壤水分再分布及土壤蒸发的变化规律,结果表明,地表湿润圈的大小直接影响到蒸发量的大小。滴头流量越大,地表的湿润半径越大,蒸发损失也越大。滴头流量的大小直接影响土壤水分在水平和垂直方向的动态。滴头流量不同,其蒸发损失也不同。

The crop production was limited seriously by water shortage in arid and semi-arid region of north China. Alternate partial root zone irrigation （APRI） is an effective water-saving irrigation technique. The appropriate dripper discharge should be selected for different soil texture and climatic conditions. In this paper, the laws of soil moisture distribution and soil evaporation in different dripper discharges were researched. The results show that the soil wetted pattern was influenced by the dripper discharge. The bigger horizontal infiltration distance resulted in greater loss of soil evaporation with the dripper discharge of 8 L/h. The deeper infiltration distance resulted in greater loss of deep infiltration under the dripper discharge of 2 L/h.