1.Institute of Forest Ecological, Environment and Protection, Chinese Academy of Forestry, 100091, Beijing; 2.Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water resources, 712100, Yangling, Shaanxi: China
Abstract：To probe into the effect of different vegetations on dynamic change of soil moisture and its evaporation process, soil moisture evaporation under four different vegetation coverage conditions were compared from July to October in 2001 in Guyuan county of Ningxia. The results indicated the order of soil evaporation intensity was abandoned land> Larix principis-rupprechtii Mayer. stand>Srtemisia vestita Wall.+ Stipa bungeana Trin. stand>Hippophae rhamnoides Linn. stand in the observation period. And soil evaporation in the quick-growth period (from July to August) was stronger than that in the later growth season (from September to October). Meanwhile, test of soil moisture evaporation day and night by stages showed that soil moisture evaporation in the night in the observation period appeared negative because especially after September and October, which indicated that amount of condensation water in the night is more than that of evaporation accordingly.
2005, Vol. 3 
