Water-vapor movement in soils is a complex process, controlled by both diffusion and advection and influenced by pressure and thermal gradients acting across tortuous flow paths. Wide-ranging interest in water-vapor transport includes both theoretical and practical aspects. Just how pressure and thermal gradients enhance water-vapor flow is still not completely understood and subject to ongoing research. Practical aspects include dryland farming (surface mulching), water harvesting (aerial wells), fertilizer placement, and migration of contaminants at waste-sites. The following article describes the processes and practical applications of water-vapor transport, with emphasis on unsaturated (dry) soil systems.
Revised: March 23, 2007 |
Published: November 16, 2001
Citation
Gee G.W., and A.L. Ward. 2001.Vapor Transport in Dry Soils. In Encyclopedia of Water Science, edited by Stanley W. Trimble. 1012-1016. New York, New York:Marcel Dekker.PNNL-SA-35086.