Wind Erodibility of Soils from North Darfur State

Abstract

Wind erodibility of soils (WE) is a prime factor for the prediction, assessment and mapping of wind erosion. Hence, this study was undertaken to generate WE data and pertinent relationships for North Darfur State. Surface soil samples (0-3 cm) were collected from forty farms scattered all over the state. Non-erodible soil particles (NEP) (> 0.84 mm in diameter), WE and various relevant physical and chemical soil properties were determined. Regression analysis showed that NEP significantly (P<0.001) increased with increase in organic matter (r2=0.825), clay (r2=0.754), silt (r2=0.737) and clay/ (silt + sand) ratio (r2= 0.663), and decreased with increase in sand (r2=0.761), (silt + sand) / clay ratio (r2 = 0.766) and (silt + sand) / (clay + organic matter) ratio (r2= 0.811). The four basic soil properties and their ratios gave the reverse effects on WE with slightly lower coefficients of determinations. Although organic matter is a slightly better predictor of both NEP and WE than (Si+S) / (C+OM) ratio, the latter is preferred because it integrates in addition to OM resilient soil properties. A multiple regression equation with a relatively high coefficient of determination (R2 = 0.830) may also be used for predicting NEP from knowledge of the four prime soil properties. These properties accounted for only 62% of the variation of WE, thus it is not recommended for prediction purposes. The determined wind erodibility groups correlated very well with those established elsewhere.