INVESTIGADORES
BUSCHIAZZO Daniel Eduardo
artículos
Título:
Threshold wind velocity as an index of soil susceptibility to wind erosion under variable climatic conditions
Autor/es:
DE ORO, L.; BUSCHIAZZO, D.E.
Revista:
LAND DEGRADATION & DEVELOPMENT
Editorial:
Wiley & Sons
Referencias:
Año: 2009 vol. 20 p. 14 - 21
ISSN:
1085-3278
Resumen:
Wind erosion starts when the threshold wind velocity (¦Ìt) is exceeded. We evaluated the sensitivity of ¦Ìt to determine the wind erosion susceptibility of soils under variable climatic conditions. Three years field data were used to calculate ¦Ìt by means of the equation ¦Ìt = ¨± - ¦Ò ¦µ-1 (¦Ã), where ¨± is the mean wind speed (m s-1), ¦Ò the ¨± standard deviation (m s-1), ¦Ã the saltation activity and ¦µ the standard normal distribution function of ¦Ã. Saltation activity was measured with a piezoelectric sensor (Sensit). Results showed that ¨± of the whole studied period (3.41 m s-1) was lower than ¦Ìt (7.53 m s-1), therefore, wind erosion was produced mainly by wind gusts. The ¦Ìt values ordered in the sequence: Winter (6.10 m s-1) < Spring (8.22 m s-1) = Summer (8.28 m s-1) < Autumn (26.48 m s-1). Higher ¦Ìt values were related to higher air humidity and lower wind speeds and temperatures. The ¦Ìt 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 ¦Ìt and erosion amounts of Winter were produced by a scarce number of gusts during eroding storms. We concluded that ¦Ìt is useful as an index of soil susceptibility to wind erosion of different climatic periods. The use of a unique ¦Ìt value in wind erosion prediction models can lead to erroneous wind erosion calculations.