The impact of land use practice on the spatial variability of soil physicochemical Properties at Wondo Genet, Southern Ethiopia

The present research deals with changes that occurred in physical, chemical, and microbiological soil qualities due to different land-use practices. Soil samples were taken from three nearby soil plots with varying land uses, including natural forest, plantation forest, and agricultural land at both 0–30 and 30-60 cm soil depth and at each land-use category, fifteen samples were taken for each land use type. Total nitrogen, soil organic carbon, and microbial biomass were determined by the micro-Kjeldahl method, and fumigation extraction method, respectively. Using kriging interpolation techniques in a GIS framework, geostatistical analysis was done to depict the spatial variability of soil parameters. The result shows that among all land use patterns the highest bulk density was recorded from agricultural land /Khate farm (0.96±0.018%) followed by plantation forest /Cupressus (0.93±0.012%) and NF (0.81±0.03%). Soil organic carbon was found to be higher in Natural forest (4.25±0.28%) followed in decreasing order by plantation forest/Podocarpus (2.77±0.49%) and agricultural land/Coffee (2.92±0.16%). Soil Total nitrogen was higher in Natural forest (0.37±0.024 μg/g) in the soil's uppermost layer and significant with PF and agricultural land. Microbial biomass carbon was higher in Natural forest (939.84±46.0μg/g) and plantation forest /Grevillea (712.8±48.4μg/g) and agricultural land /Enset (570.2± 38.8μg/g). Similarly, microbial biomass N was higher in Natural forest (81.0.4±3.9μg/g) and significant with plantation forest /Gravellea (60.08±4.2μg/g) and agricultural land /Enset (40.96± 3.3μg/g). The result of the present study indicates that the microbial biomass and physicochemical properties of soil are highly correlated with the type of vegetation and soil depths.