In order to understand the soil moisture migration rules of the lawn with subsurface drip irrigation (SDI) , the infiltration experiment of SDI on the grass in the field was carried our by two water supply modes single and grid emitters. The results showed that under the water supply of single emitter, the soil moisture content changed quickly in horizontal direction when the irrigation lasted for 1 hour, the water could move 15 cm from the head of emitter within 45 min, 20 cm within 60 min, and 30 cm with 90 min. The rate of variation of soil water changed smoothly with the range of 20 - 30 cm. Under the water supply of grid emitters, superimposition effects were observed among the emitters. When the irrigation lasted for 1 hour by the grid emitters with the distance of 30 cm, the soil moisture content increased sharply ranged from 0-15 cm, superimposition effects appeared after 90 min. There was no obvious superimposition effect of soil moisture in perpendicular direction. After the irrigation, soil moisture would move to the area with the low moisture content, and the re-distribution was formed with very gentle changes, and these areas became stable in 24 hours after irrigation.%为了探讨草坪在地下滴灌条件下的土壤水分运移规律,通过在单滴头和网格滴头2种供水条件下,对田间草坪进行了地下滴灌的入渗试验研究.结果表明:在以单滴头供水条件下,灌水时间持续1 h,土壤水分在离滴头水平距离0～15 cm内运移较快,土壤含水率变化迅速,45 min能到达15 cm的距离,60 min能到达20 cm的距离,90 min后才能到达30 cm的距离.但在20～30 cm范围内土壤含水率变化较平缓；在以网格滴头供水条件下,滴头间存在水分叠加效应.在以30 cm边长的网格滴头对草坪土壤供水条件下,灌水时间持续1 h,在相邻两滴头间45°角的剖面上,0～15 cm距离范围,90 min后会产生土壤水分的叠加效应,土壤含水率骤然上升,能有效减少出现灌水不均匀与灌水盲区的概率.垂直于毛管向外的切面上土壤水分的叠加效应不明显.灌水结束后,土壤水分还会向含水率较低的区域运移,发生再分布,但变化非常平缓,且在灌水结束后24 h达到区域稳定.
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