35 巻 (1993) 3 号 p. 217-225
It is expected that permeable dune sand areas have high potential of recharge to groundwater. The purpose of this paper is to clarify the soil moisture movement mechanism in unsaturated zone on the bare soil surface site on the Syounai Dune area. Actual evaporation duringll fine weather days was about 5-26% of the Penman potential evapo-transpiration. Evaporation experiment indicated that the thickening of dry sand layer restricted evaporation. As the result that the dry sand layer restrained evaporation, we could expect that the amount of recharge in the sand dune area increased relatively.