Abstract
Soil quality underpins agricultural productivity, environmental health, and food security, yet in dry sub-humid regions such as Borno State, Nigeria, soils face growing risks of degradation and contamination. This study assessed the physical, chemical, and biological characteristics of soils to evaluate spatial variability, contamination levels, and implications for sustainable land use. Soil samples were analyzed for moisture, bulk density, porosity, heavy metals, uranium, thorium, parasites, and enteric bacteria using standard laboratory procedures. Results showed notable spatial variations: Kaga LGA recorded the highest mean soil moisture (7.18 ± 4.62%) and lowest bulk density (1.49 ± 0.07 g/cm³), while Nganzai had the lowest moisture (4.07 ± 6.98%) and highest bulk density (1.54 ± 0.11 g/cm³). Porosity ranged from 41.85 to 43.73%, indicating moderately aerated soils. Most heavy metals were within USEPA thresholds; however, localised excesses of Zn, Pb, Cr, and Ni occurred. Uranium (0.97–9.73 mg/kg) and thorium (2.24–8.85 mg/kg) were detected at variable concentrations. Biological analysis revealed faecal contamination with Aspergillus niger, Penicillium, Ascaris lumbricoides, hookworms, Salmonella Typhi, and Escherichia coli. The findings underscore the concurrent issues of nutrient depletion and contamination, emphasizing the need for integrated soil fertility management, contamination monitoring, and enhanced biosecurity to safeguard land resources in Borno State.
Key words: Soil quality, agricultural sustainability, environmental sustainability, Northern-Borno Nigeria.
