半湿润沙地干沙层特性的初步研究

半湿润沙地的干沙层厚度的日变化与当地地温、气温日变化呈相似的周期变化。有植被覆盖沙地干沙层的发展速率呈先慢后快趋势；裸沙地干沙层发展速率呈先快后慢的趋势，农作物地干沙层的发展速率较草地快。裸沙地干沙层发展到７－８ｃｍ厚度时，干沙以下的水层中的水与空气中的水汽变换很弱。

Preliminary Study on the Dry Sand Layer of Sandy Land in Semi-humid Region

aily change of dry sand layer thickness in semi-humid sandy land has the same period with daily earth temperature air temperature change.The development volety of dry sand layer covered different vegetation is from fast to slow.The development volety of dry sand layer covered no vegetation is from slow to fast.The development volety of dry sand layer in crops is more thickness than in grassland.The moisture under dry sand layer is very slow change with the moisture of air when the dry sand layer reach 7-8cm.