Soil Quality Index of land impacted by anthropogenic activities in coastal Ghana

The excessive use of weedicide and fertilizer by farmers, indiscriminate waste disposal as well as unregulated and pervasive chemical use for mining and industry has huge impacts on the sustainability of soil resource. However, land use-specific characterization of soil has not been extensively studied. The soil quality of 4 different land use classes-cultivated soils, industry, decommissioned waste dump and forest reserve that depict different anthropogenic effect in urban and rural settings were assessed. Twelve composite samples were taken per site at a depth of 30cm with an auger, air dried and sieved with 2mm mesh and portions used for analysis. Soil mineral parameters analyzed include bulk density, reaction pH, organic carbon, total nitrogen, phosphorus, exchangeable cations: sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), and extractable trace elements: manganese (Mn), nickel (Ni), iron (Fe), cadmium (Cd), copper (Cu), zinc (Zn) and lead (Pb). The mean %SQIs for soil samples collected from cultivated soils, decommissioned dump, industrial and forest reserved sites are 54.9%, 57.6%, 60.6% and 61.4% respectively. Mean concentrations of Cd, Pb and Ni are 0.020 mg/kg, 1.301 mg/kg and 0.213 mg/kg, respectively. There were significant variations pairwise between cultivated soil and forest reserve soil and then cultivated and industrial soil (p< 0.05). Assessing soil quality (SQ) through evaluation of changes in soil properties across different land use classes is an essential tool for proper management to promote sustainable use to sustain life.