Soil Quality Of Selected Farms In Asesewa In The Eastern Region Of Ghana

Abstract

Increasing demand for food supply, coupled with the financial needs of smallholder farmers has triggered the use of farm management practices that threaten the quality of agricultural soils. These practices include annual bushfire for clearing the land, yearly plowing and the indiscriminate application of pesticides. These practices have the propensity of reducing the soil quality. Soil quality indicators provide essential knowledge on the capacity of soils to function within the ecosystem and support plant growth. This work studied the soil quality status of farms from the Upper Manya Krobo District, Asesewa by measuring their physical, chemical and biological indicators. The results for the chemical indicators show strongly acidic to neutral soils with pH range of 4.88-7.26. Electrical conductivity measurements were low in all the soils 0.043-0.317 (dS /m) with soils showing high percentage organic matter between 2.70%-7.90 %. The number of exchangeable sites for cations (cation exchange capacity) was between 10.77-33.31(cmol(+)/Kg). For exchangeable bases, Calcium was 3.21-11.56 (cmolc/kg) , Magnesium was in a range of 0.69-3.12(cmolc/kg), 0.63-1.27(cmolc/kg) for Potassium and 0.27-0.57(cmolc/kg) for Sodium. The biological indicators show a total microbial population in the soils for serial dilutions of 10-4 and 10-5for bacteria. Bacterial population for sixteen farms was within the acceptable range in pesticide treated soils however, they were not present in population that can support microbial activities and processes enough in the soil. A great number of fungal isolates in the soil was not inhibited by pesticide application especially, Streptomyces sp. compared to control groups.