Threshold wind velocity as an index of soil susceptibility to wind erosion under variable climatic conditions
Autor: | Daniel Eduardo Buschiazzo, Laura Andrea de Oro |
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Jazyk: | angličtina |
Rok vydání: | 2009 |
Předmět: |
ARGENTINA
Agricultura SALTATION ACTIVITY CLIMATIC CONDITIONS Soil Science Storm Development Atmospheric sciences Wind speed Standard deviation Wind profile power law CIENCIAS AGRÍCOLAS Saltation (geology) Wind gust Soil water Environmental Chemistry Environmental science Aeolian processes THRESHOLD WIND VELOCITY Agricultura Silvicultura y Pesca General Environmental Science WIND EROSION |
DOI: | 10.1002/ldr.863 |
Popis: | 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 |
Databáze: | OpenAIRE |
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