Chapter 13 - Arid Catchments

Abstract

This chapter discusses the use of isotopes in arid catchment studies. It also explores the isotopic effect of evaporation on waters in arid catchment basins. The hydrology of arid environments and the prevalence of evaporation require an understanding of the arid system for proper sampling to obtain water representative of the system. The sampling of precipitation presents particular problems because of the extreme variability and sporadic nature of precipitation in arid regions, and the resultant variability in stable isotopic composition. Directions of future research concerning the use of isotopes in arid catchment studies will probably be twofold. One major focus will be on attempts to determine the amount, mode, and rate of infiltration. Another major focus should be on determining and protecting the quality and quantity of the fresh water reservoir. These studies may include attempts at amelioration of the salinity build up because of agricultural use. Additional uses of isotopes studies that lend themselves to arid catchment basins are studies of climate change. Arid regions are generally the most sensitive to climate change. The Great Basin in western North America, the most arid region in the United States, has been identified as being more sensitive to climate change than any other region.