关键词: 沙坡头, 土壤, 吸湿凝结, Penman-Monteith方程

Abstract: The process and amounts of moisture absorption and water condensation in the surface shallow layer of sandy soil are studied preliminarily by the method combining field measurement with theoretical calculation. The results showed that the formation process of water absorption and condensation in sandy soil is composed of two stages. The first one is the process of water molecular absorption determined by the physical properties of sandy soil. The amounts of water absorbed is affected by temperature and humidity(moisture) of air and soil, and the maximum is not bigger than the maximum moisture absorption of sandy soil. The second is the process of water condensation determined by air vapor, soil surface temperature and the available energy of soil. The calculating values from Penman Monteith equation coincide with the measured data, which has proved the feasibility of applying the method to study water absorption and condensation in sandy soil.

Key words: Shapotou, Sandy soil, Water absorption and condensation, Penman Monteith equation