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Stanovení erodovatelné frakce půdy různými metodami
Čechal, Vladimír
Wind erosion is one of the mail reasons of soil degradation. The amount of wind erodible fraction (EF) is the key parameter regarding wind erosion susceptibility of the soils. As the EF of the soil is considered percentage of aggregates < 0, 84 mm in diameter. Dry sieving with use of rotator or flat sieves is the standard method for EF estimation The main aim of this study is comparison of standardized flat sieving method against the use of equations for predicting EF. The first of these equations, EF = 29,09 + (0,31.sand) + (0,17.silt) + (0,33.sand/clay) - (2,59.ogranic matter) – (0,95.CaCO3), was proposed by D. W. Fryrear in 1994. But it has not been tested outside of USA, Spain and Argentina, so far. Another equations used here, EF = 9,98 + 6,91.(sand/clay) + (14,1/organic matter) a EF = 4,77 + 7,43 (sand/clay) + (27,6/ organic matter), were proposed by M. V. López in 2007 during his research of EF. The results show that the values obtained by calculating these equations do not match the EF obtained by means of a flat sieving. With the use of the statistical program Unistat the new equations have been proposed, EF = 84,94 - (0,03.sand) - (1,36.clay) + (1,90.Corg) + (43,14.CaCO3), EF = 84,77 - (0,02.sand) - (1,34.clay) + (0,95.humus) + (42,71.CaCO3) and EF = 21,25 + (0,52.silt) + (7,63.sand/clay) + (0,41.humus) – (7,44.CaCO3), for the determination of EF in the surveyed soil samples.
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