Wind erosion in loess soils of the Semiarid Argentinian Pampas

This study is the first effort to measure wind erosion in the field in Sout h America. Wind erosion of two bare soils, a loamy sand surface Typic Ustip samment and a sandy loam surface Entic Haplustoll of the Semiarid Argentini an Pampas, were measured in the field during wind storms that started on Ju ne 16 (mean wind speed = 14 km/h; storm duration 103 h) and June 30 (mean w ind speed = 21.4 km/h; storm duration 25 h) of 1995, Measurements were made with dust samplers placed at heights of 0.135, 0.54, and 1.47 m within a 1 -ha field. Mass nux (amount of eroded material within a given time) was larger in the Ustipsamment soils than in the Haplustoll soils in both storms. A maximum a mount of transported dust was found within the limits of the studied field (100 x 100 m(2)) during the June 16 wind storm and outside the studied fiel d during the June 30 wind storm. This was attributed to the variation in wi nd direction on June 16, The total amount of material eroded from the field during each storm reache d 1.82 mt ha(-1) in the Ustipsamment and 0.29 mt ha(-1) in the Haplustoll o n June 16 and 0.98 mt ha(-1) in the Ustipsamment and 0.75 mt ha(-1) in the Haplustoll on June 30, Wind velocity was high enough to erode the loosened Ustipsamment but not the better structured Haplustoll on June 16, On June 3 0, wind velocity was high enough to erode both soils, but a shorter storm d uration did not allow the erosion of large amounts of soil.