Assessment of the Effects of Some Heavy Metals on Biological Properties of Soil around Sharada Industrial Area of Kano, Nigeria
Ado Garba* and Isah BI
Published: November 04, 2022
Abstract
This research assessed the effects of heavy metals on biological properties of soils in Kano metropolis in view of the fact that the contamination of the soil by toxic heavy metals has become an issue of global concern; more so because information on the effect of heavy metals on biological properties of soils in Kano metropolis is limited and inadequate for promoting the very crucial environmental sustainability and harmony. Field investigation and laboratory analysis were the main sources of generating data for the study. The study area was divided into two locations: effluent-affected and control locations. Each of the locations was divided into 4 grid squares within which samples were collected. The properties investigated include: Microbial biomass carbon, phosphate and urease. The results of the analyses were subjected to statistical analyses using SPSS software and Microsoft excel to undertake t-test of means, ANOVA, correlation and regression at 95% confident limit. The results revealed that all heavy metals were found to be higher in the effluent-affected locations and that rainfall enhanced the dilution and leaching of the heavy metals in the soil, resulting in the low mean values of heavy metals in the wet season.Microbial biomass carbon, phosphatase and urease activities were found to be higher in all the effluent-affected locations as a result of the resistance of soil microbes to heavy metals toxicity coupled with high pH and temperature. Microbial biomass carbon negatively correlated with Cd (r = - 0.54*), phosphatase was negatively correlated with Cd (r = - 0.22) and Ni (r = - 0.09), while urease was negatively correlated with Cd (r = - 0.26*) and Ni (r = - 0.008). The results in general indicate that the determination of the biological properties of the soils reflects the microbial activities in soils and so these properties are considered as soil quality indicators. The study recommends reduction of aerial contamination from industrial operation. Private treatment plant should be established for the treatment of the effluent. The treatment system charge for the cost of treatment and monitoring for compliance are to be by government.
Keywords: Biological; Microbial biomass carbon; Phosphotase; Pollution; and Urease