Abstract
To minimize the amount of carbon dioxide released into the atmosphere, an important calculation needed for large tree plantations in arid regions is that of the extent of evaporation loss from the soil water budget at the soil surface. In Australia, there are vast expanses of arid regions where annual rainfall accumulations are less than 300mmy-1. Most land in Leonora, WA is presently used as pasture although some arid species of trees are also being grown despite the low annual rainfall. In addition, hardpan lying beneath the thin surface soils and contains a high concentration of salt. The author has investigated the rate of evaporation at the soil surface to obtain the preliminary data needed for tree plantations in the region. A model for calculating the evaporation at the soil surface in an arid region has been developed based on the laws of thermodynamics and of Boyles-Charles, and from some of the soil properties, including soil temperature and water content.
