Soil wind erosion influenced by clay amendment in the inland Pacific
Northwest, USA
Abstract
Soil clay content is one of the primary intrinsic soil properties
affecting soil erodibility, but few studies have tested the effects of
clay amendment on soil wind erosion. The objective of this study was
therefore to evaluate the effect of progressive clay amendment on soil
wind erosion in the inland Pacific Northwest (iPNW), where there is a
high soil erodibility risk due to the arid and semi-arid environment.
Clay amendment significantly increased crust crushing energy when
physical soil crusts formed after simulated rainfall. Crusts were then
subject to simulated tillage to create an erodible soil surface before
determining wind erosion in a wind tunnel. Soil loss significantly
decreased with increasing clay amendment, even for low clay amendments
(2%). In addition, the rate of change in erosion decreased with
increasing amounts of clay amendment. Clay amendment was more effective
in decreasing soil loss for two sandy loams or soil types with lower
clay content. Clay amendment decreased soil loss primarily due to its
impact on increasing aggregate geometric mean diameter (GMD), but
aggregate crushing energy is also important in decreasing soil loss in
terms of decreasing abrasion flux. Clay amendment is thus an effective
way to restrain land deterioration in terms of increasing crust crushing
energy, aggregate GMD, and decreasing abrasion flux.