Abstract
Micro-meteorological observations and measurements of heat and moisture transfer in sandy soil were carried out to obtain basic data for conserving irrigation water in the United Arab Emirates (U.A.E.) from 1996 to 1998. This paper shows monthly averaged diurnal changes of air temperature and relative humidity, wind velocity, downward long-wave radiation, downward short-wave radiation and soil temperature. In addition, the drying of the soil surface layer was monitored during three water-ing-evaporation trials. Time variations and vertical profiles of the soil temperature, soil pore relative humidity and water vapor density were obtained by a “soil thermo-hygrometer” method and the volumetric water content was determined by a “heat probe” method. The depth of drying estimated by the two methods agreed closely and it is concluded that the “soil thermo-hy-grometer” method is a valid means for monitoring post-irrigation drying phenomena.
