The world’s arid lands appear to be enlarging, and droughts are contributing to the economic devastation of the whole world. Both industrialized and developing countries suffer from this crisis. As pointed out in Section 1.7.2, the deterioration of productive land into desert-like conditions continues without letup at the rate of 14.8 million acres a year. In the U.S., it is reported that desertification faces falling water tables and increased groundwater salinity in the southwestern states. Arid lands have been exploited for their agricultural potential. Water practices developed for temperate climates may not be suitable in arid lands. For environmental and economic reasons, it is necessary to reevaluate the problems existing in the arid lands as well as in desert areas. The contents of this chapter include

1. Evaluation of arid land and desert-like environments for sand-heat interaction, sand-wind interaction, and sand-water interaction

2. Development of techniques for increasing the supply of usable water 3. Reducing the demand for water supply, as well as delivery, and proposing an integral sys-

tem for the purpose of antidesertification measures.