Threshold wind velocity as an index of soil susceptibility to wind erosion under variable climatic conditions

Authors
de Oro, Laura Andrea; Buschiazzo, Daniel Eduardo
Publication Year
2009
Language
English
Format
article
Status
Published version
Description
Wind erosion starts when the threshold wind velocity (μ t ) is exceeded. We evaluated the sensitivity of μ t to determine the wind erosion susceptibility of soils under variable climatic conditions. Three years field data were used to calculate μ t by means of the equation μ t = ū - σ Φ -1 (γ), where ū is the mean wind speed (m s -1 ), σ the ū standard deviation (m s -1 ), γ the saltation activity and Φ the standard normal distribution function of γ. Saltation activity was measured with a piezoelectric sensor (Sensit). Results showed that ū of the whole studied period (3.41 ms -1 ) was lower than μ t (7.53 ms -1 ), therefore, wind erosion was produced mainly by wind gusts. The μ t values ordered in the sequence: Winter (6.10 ms -1 ) < Spring (8.22ms -1 ) = Summer (8.28 m s -1 ) < Autumn (26.48 m s -1 ). Higher μ t values were related to higher air humidity and lower wind speeds and temperatures. The μ t values did not agree with the erosion amounts of each season, which ordered as follows: Summer (12.88 t ha -1 ) > Spring (3.11 t ha -1 ) = Winter (0.17 t ha -1 ) = Autumn (no erosion). Low μ t and erosion amounts of Winter were produced by a scarce number of gusts during eroding storms. We concluded that μ t is useful as an index of soil susceptibility to wind erosion of different climatic periods. The use of a unique μ t value in wind erosion prediction models can lead to erroneous wind erosion calculations.
Fil: de Oro, Laura Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina
Fil: Buschiazzo, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina
Subject
ARGENTINA
CLIMATIC CONDITIONS
SALTATION ACTIVITY
THRESHOLD WIND VELOCITY
WIND EROSION
Agricultura
Agricultura, Silvicultura y Pesca
CIENCIAS AGRÍCOLAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/81725