ASSESSMENT OF PHYSICAL AND CHEMICAL PROPERTIES OF SOILS IN KWARA STATE POLYTECHNIC FOREST RESERVES

Abstract

The different features of soil greatly affect the flora and vegetative diversity of a forest. The physical and chemical characteristics of soils in the Kwara State Polytechnic Forest Reserve were evaluated to assess the fertility and productivity status of the soils. Three composite soil samples were collected randomly from different locations at the depth of 0-20cm, 20-60cm, and 60-100cm using soil auger. The physical parameters evaluated include: soil texture using hydrometer, soil infiltration rates and capacity by double ring infiltrometer, soil temperature using soil thermometer, and available soil moisture content by digital soil moisture meter. Results of the soil particle size analysis revealed that soil in the study area is sandy loam, using textural classification triangle chart. This indicates that the soil is generally very light-textured with sand percentage averaging more than 80% and loam is 20%. The estimated average infiltration rate of the soil in the study area is 96.9mm/hr and the values of infiltration capacities (K) were generally high and varied from 0.00956cm/s to 0.0104cm/s. The results of moisture contents for the sampling location points (Point A, B, and C) around the study area are; 1.08 %, 1.05%, and 1.09%, respectively. Similarly, the observed soil temperatures are; 6.7^oC, 5.4^oC, and 7.8^oC, respectively. Chemical analysis results revealed that the soil pH was moderately to slightly acidic and it ranged from 5.30 to 6.87. The average organic carbon ranged from 0.142-0.267% of the entire soil nutrients relating to soil fertility. The available phosphorous content of the soil is high which ranged from 20.276 to 28.342mg/l. The sodium status of the soil is generally low which ranged from 0.156 to 0.653me/l. The exchangeable sodium percentage (ESP) value of the soil ranged from 5.90 to 10.0%. The calcium status of the soil is generally moderate which ranged from 4.36 to6.22 me/l. Magnesium been the dominant cation ranged from 1.16 to2.26 me/l. The organic matter of the soil is moderate as the values obtained ranged from 0.133 - 0.165%. The cation exchange capacity (CEC) of the soil ranged from 4.76 to 5.52me/l. Therefore, soil physical and chemical properties were the dominant factors influencing the extent of decomposition process. Thus, the forest reserve serves as protection for the soil as well as promoting the fertility and productivity of the soils to support a flourishing vegetation types in the study area.