Heat Balance and Soil Moisture in the Loess Plateau, China

Abstract

A three-layer soil model was used for clarifying the heat balance and soil water content in the Loess Plateau, China, and applied to actual bare soil fields (Tottori Sand Dune and Shenmu District, Shaanxi Province, China). The difference between the observed and calculated evaporation per day was approximately 0.18 mm (5 W m-2) to 0.21 mm (6 W m-2). Because of its moderate mixture of sand, silt and clay, yellow loessial soil in Shenmu affects water retentivity and restriction of evaporation from the soil surface. The seasonal change of heat balance and soil water content was examined using meteorological data in Yulin near Shenmu. The annual means of sensible heat and latent heat flux were 23 W m-2 and 19 W m-2 (239 mm per year), respectively. The soil water content of the second and third layers remained comparatively high in winter.