Premium
On the effect of air humidity on soil susceptibility to wind erosion: The case of air‐dry soils
Author(s) -
Ravi Sujith,
D'Odorico Paolo,
Over Thomas M.,
Zobeck Ted M.
Publication year - 2004
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2004gl019485
Subject(s) - environmental science , wind speed , aeolian processes , humidity , soil water , water content , moisture , relative humidity , erosion , atmospheric sciences , arid , soil science , hydrology (agriculture) , meteorology , geology , geotechnical engineering , geography , paleontology , geomorphology
Wind erosion is a widespread process in drylands, and contributes to loss of soil fertility, alteration of atmospheric radiation, and air pollution. Erosion occurs when wind speed exceeds a certain threshold, which depends on a number of factors, including surface soil moisture. It is shown that in air‐dry soils surface moisture and threshold wind speed depend significantly on air humidity. Thus, in arid regions variations in surface soil moisture can be significantly affected by changes in atmospheric humidity, with an important effect on wind erosion potential. Wind tunnel tests were conducted to investigate this dependence of threshold velocity on air humidity in air‐dry soils. It was found that at these moisture levels, the threshold velocity decreases with an increase in air humidity. This result is explained by the effect of hygroscopic forces and by their dependence on soil matric potential in dry soils.