Resumo

AVECILLA, Fernando; PANEBIANCO, Juan Esteban  e  BUSCHIAZZO, Daniel Eduardo. Wind erosion and pm₁₀ emission in two agricultural soils of La Pampa province, Argentina. Cienc. suelo [online]. 2019, vol.37, n.2, pp.209-224. ISSN 1850-2067.

The objective of this study was to evaluate the wind erosion and emission of fine particles (PM₁₀) on two agricultural soils: a loam soil (F) and sandy loam soil (AF). Measurements were made during two consecutive years at two experimental plots of 80 x 200m oriented north-south. The horizontal mass transport (Q) and the PM₁₀ emission were quantified. The average Q in F (6.955E-05 kg m^-2 s^-1) was higher than in AF (4.19E-06 kg m^-2 s^-1) due to the higher wind speeds and lower vegetation cover in F. In F the mass transport increased linearly with distance, while in AF it stabilized between 100 and 150m, indicating that on fine-textured soils the maximum Q could be reached at greater distances than at coarser textured soils. The PM₁₀ emission was higher in F (5.05E- 09 kg m^-2 s^-1) than in AF (6.64E-10 kg m^-2 s^-1), probably on one hand due to the high Q occurred in F and on the other hand, to the different composition of the material transported by saltation, composed predominantly by aggregated fine particles that were progressively fragmented, emitting PM₁₀. On the contrary, in AF the material transported by saltation is predominantly composed of individual particles that are fragmented to a lesser extent. For this reason, the emission efficiency was also higher in F for all the wind-erosion events. However, we found that this parameter changes depending on the weather (average wind speed) and soil conditions (aggregates size distribution of topsoil) that prevail during each erosive event, even on the same soil.

Palavras-chave : Wind erosion; Soil; PM₁₀; Mineral dust.