Effect of Sustainable Land Management Practices on the Soil Erodibility at the Plateau of Abomey (Centre of Benin)

Abstract

The soils of Benin in general and those of the department of Zou, in particular, are highly degraded. This study aimed to evaluate the effectiveness of sustainable land management practices on soil erodibility in two villages in the Plateau of Abomey. Soil samples were collected on plots under Sustainable Land Management (SLM) measures (direct seeding, maize residue management and soybean-cereal rotation) and on their adjacent control. The soil samples were prepared and analyzed in laboratory to determine variables such as soil permeability, organic matter content, and particle size. Soil erodibility was determined as proposed by Wischmeier & Smith. The effect of SLM practices was significant (0.02) on soil permeability. On plots under SLM measurements, soil permeability is higher with an average of 93.97 mm/h at Folly and 82.43 mm/h at Hanagbo. SLM measurements significantly (0.04) added organic matter to the soil. The average organic matter of the plots under SLM measures in Folly varies from 0.73% to 1.39% while it varies from 0.49% to 0.73% in the control plots. In Hanagbo, the average organic matter of the plots under SLM measures varies from 1.86% to 2.48% against 1.41% to 1.66% for the control plots. Regarding soil erodibility, it was found that the influence of SLM measures is significant in both villages. In villages, direct seeding and maize residue management significantly (0.008) reduced soil erodibility compared to their adjacent controls, while the soybean-cereal rotation measure increased soil erodibility compared to plot witnesses. The average soil erodibility of plots under SLM measures varies by 0.21 t⋅h/Mj⋅mm at 0.38 t⋅h/Mj⋅mm in the village of Hanagbo and 0.25 t⋅h/Mj⋅mm at 0.38 t⋅h/Mj⋅mm in the village of Folly. It varies from 0.24 t⋅h/Mj⋅mm at 0.28 t⋅h/Mj⋅mm for the control plots at Hanagbo and 0.31 t⋅h/Mj⋅mm at 0.37 t⋅h/Mj⋅mm in Folly. These practices can therefore be used for the sustainable use of agricultural land.