Soil degradation is a serious problem for people living in watersheds of Benin. This degradation is mainly due to poor farming practices and because of this poor management annual maize production reduced critically. This study was aimed to estimate the state of physical and chemical soil degradation of three watersheds of southern Benin. One reference site representing sacred forest was also chosen for comparing the results of watershed. Soil cores were also collected from these selected sites. Physical and chemical parameters were determined from the collected soil samples. Results of study revealed that the watershed soil is more compact and lower in nutrients than the soil of reference sites. The bulk soil density was significantly higher in Govié and Lokogba watersheds compared to their reference site. As a result of intensive farming and water erosion, root biomass of the soil has significantly decreased from 86 to 82% in Govié, 69 to 67% in Lokogba and 75 to 70% in Linsinlin. The total soil nitrogen of watershed declined significantly, from 33 to 24% in Govié, 32 to 30% in Lokogba and 38 to 25% in Linsinlin. Available soil phosphorus decreased from 10.93 ppm to 7.11 ppm in the Lokogba watershed. The soil phosphorus of Linsinlin watershed was reported highest from 5.5 ppm to 8.00 ppm compared to the reference site. The soil organic matter of watershed declined from 38 to 37% in Govié and 68 to 66% in Lokogba. Lokogba watershed is the most degraded one compared to three watersheds studied.

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