陕北水蚀风蚀交错区苜蓿地土壤水分过耗与恢复

采用野外定位观测法研究水蚀风蚀交错区苜蓿(Medicago sativa)草地土壤水分在天然降水作用下的恢复过程。结果显示:苜蓿地翻耕后,在降水作用下土壤水分有明显的恢复过程,第一年,150cm以上土壤水分得到一定恢复,第二年深度达到300cm,但上层土壤含水量并未增加;该地块植被大量消耗土壤储水导致土壤干燥化,高耗水植被消除后,土壤含水量逐渐增加。

Soil Water Restoration of Alfalfa Land in the Wind-water Erosion Crisscross Region on the Loess Plateau

By a field positioning observation,we studied soil moisture restoration after rainfalls in the cultivated alfalfa pasture of the wind-water erosion crisscross region of the Loess Plateau.Results show that following a rainfall the ploughed alfalfa land had obviously restored much water.In the year after the land plough,moisture of soil 150cm depth down from surface restored considerably.In the next year,though soil water of 300cm depth from surface restored after a rainfall,the upper soil water did not increase.The water consuming vegetation had ingested most of the soil water,leading to the aridity of the land.Removal of the water-consuming vegetation would gradually restore the soil water.