Soil physico-chemical properties and fertility status of long-term land use and cover changes: A case study in Forest vegetative zone of Nigeria

Abstract

Proper utilization of land is essential to soil quality maintenance and sustainable agricultural development. This study was conducted to evaluate effects of land use management on physico-chemical characteristics of soils in Ekiti State, Southwestern Nigeria. In this study, a total of 105 sampling points in 35 locations comprising of the 3 land uses were sampled. Random sampling pattern of 3 sampling points per location were carried out and undisturbed soil samples were collected at depths up to 30 cm. Soil physical properties (bulk density (BD), water holding capacity (WHC), and particle size distribution) and chemical properties (organic matter content (SOM), cation exchange capacity (CEC), phosphorus (P) and organic nitrogen (SON)), were determined and evaluated. Results showed that natural forest on the overall accumulated more nutrients than plantations and cropland. The highest SOM value of 4.07 % was recorded in the natural forests, while the lowest value of 1.52 % was found in the croplands. Organic matter accumulation showed a decreasing trend in the order:  forest > plantation > cropland. Natural forest soils had significantly higher volumetric moisture content (VMC) than plantations and croplands.  C orrelation analysis of the 11 physico-chemical properties for the study area, showed a significant correlation among 70 of the 190 soil attribute pairs. Land use system reveals a significant decline of soil quality under cropland. Management systems by which soil could be improved towards the development of suitable agricultural management systems must be incorporated during land cultivation. In order to have sustainable land use systems, land use development must not be only economically sustainable but also socially acceptable and environmentally sound. Therefore, strategies to improve agricultural productivity have to seek a sustainable solution that better addresses soil fertility management.