Prevailing Physicochemical Properties of Soil Defined by Vegetation Types and Depth
By Egbe Victor N, Stanley, H. O. , Osu, C. I.This
study investigated the prevailing physicochemical properties of soils as
influenced by vegetation types and depth, with emphasis on forest and farmland
ecosystems in Port Harcourt and Bonny, Rivers State, Nigeria. Baseline
physicochemical and microbial characteristics of soil samples were assessed to
establish variations attributable to land use and vegetation cover. Soil
samples were analyzed for temperature, pH, sulphate, nitrate, phosphate, total
organic matter, soil texture, bulk density, and selected heavy metals (Lead,
Zinc, Nickel, Chromium, Arsenic, Cobalt, and Copper). In addition, baseline
microbial characteristics, including total heterotrophic bacteria and total
fungi counts, were determined using standard microbiological methods. The results
revealed significant variations in physicochemical properties across vegetation
types and locations. Soil pH ranged from slightly acidic to alkaline in both
forest and farmland soils, reflecting differences in organic matter input and
land-use practices. Forest soils generally exhibited higher total organic
carbon and lower bulk density (0.7–1.1 kg/m³), while farmland soils recorded
higher bulk density values (1.2–1.6 kg/m³), likely due to cultivation and
compaction effects. Heavy metal analysis indicated the presence of all tested
metals; however, their concentrations were low and below the Department of
Petroleum Resources (DPR) target limits, suggesting minimal contamination.
Microbial analysis showed higher total heterotrophic bacterial and fungal counts
in forest soils compared to farmland soils, indicating better microbial
activity and soil health under natural vegetation. Variations in bacterial
cultural morphology and fungal characteristics further reflected the influence
of vegetation type and soil conditions on microbial diversity. Overall, the
study demonstrates that vegetation type and land use significantly influence
the physicochemical and microbial properties of soils, providing valuable
baseline data for soil quality assessment, environmental monitoring, and
sustainable land management practices in the study area.