Assessing Impacts of Different Land Use Types on Soil Properties ın Asa and Moro Local Government Area, Kwara State, Nigeria

Abstract

Successful agriculture requires the sustainable use of soil resource, because soil can easily lose its quality and quantity within a short period of time. Agricultural practices, therefore, needed basic knowledge of sustainable use of land. This research was conducted in Asa and Moro Local Government Areas of Kwara State to assess the impacts of different land use types on soil properties in the study area. Six villages noted for farming were randomly visited and in each village, three farms planted each with maize-cassava intercrop, cashew plantation and natural forest were sampled at 0-20 cm depth for laboratory analysis of particle size, pH, carbon, nitrogen, phosphorus, exchangeable cations and extractable micronutrients. The bulk density at 0-5 cm, 5-10 cm and 10-15 cm depths were determined. Soil properties were analysed using descriptive statistics. The soil texture was sandy loam with soil pH ranging from slightly acid to acid (6.4 to 5.1). Irrespective of the local government areas and land use, organic carbon (1.83 g kg-1), Sodium (0.12 cmol kg-1), Nitrogen (0.12 g kg-1) and Phosphorus (6.15 mg kg-1) were low while Fe (134.80 mg kg-1), Mn (122.80 mg kg-1) and Zn (19.22 mg kg-1) were high. Across the local government areas, Potassium and Magnesium varied from medium to high while Calcium and Copper were low to medium. The bulk density range was medium to high (1.36 to 1.57 g cm-3) for cashew plantations and maize-cassava intercrop while it was medium (1.40 to 1.47 g cm-3) for natural forest. In conclusion, most of the cultivated soils were low in fertility, with low carbon stocks which is assumed to be due to emission losses arising from continuous cropping. The carbon sequestration status of land uses in the study area was very low. Management practices like composting, green manuring, use of organic fertilizer and residue retention is recommended.