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The quality of water discharged into Agodi Reservoir was determined by the levels of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Water samples were collected from the inlet, centre and outlet locations of the reservoir and their heavy metal contents were determined by standard methods using Atomic Absorption Spectrophotometer (AAS) over a period of twelve (12) months covering both rainy and dry seasons. Test location differences and seasonal variations were examined using ANOVA at P<0.05 to establish any gradient effect associated with pollution dynamics. Results showed no seasonal variations in all the heavy metals except for Co. Also, there is no significant variation in heavy metal concentration between the test locations. The heavy metal profile in Agodi Reservoir, measured in mg/L, was as follows: Mn (64.81) > Fe (43.75) > Zn (23.13) > Cu (12.44) > Co (0.19) > Ni (0.17) > Cd (0.12). Concentrations of Cr and Pb were below detectable level. Compared to WHO recommended limits, Co fell below while others were higher than thresholds. It is concluded that Agodi Reservoir water has a potential environmental hazard unless treated before use.

An investigation was carried out to examine the properties of top soils between 0 and 15cm under both deforested and forested zones in Bowen University, Iwo, Nigeria. Top soil samples in the deforested zone was taken from the Main Gate area of the institution while that of the forested zone was taken from the forested area opposite staff quarters of the University. The soil samples were subjected to standard laboratory tests in the University central laboratory. The results showed that deforested soil has sandy, clay and silt contents of 72.4%, 9.2% and 18.4% respectively while forested soil has 65.2%, 10.8% and 24% in the same order. Also it was discovered that soil under deforestation has organic carbon, organic matter, pH, field capacity, moisture and electrical conductivity of 0.32%, 0.55%, 6.8, 0.72 g, 126.9 g and 230 µʃ/cm respectively while soil under forest has 0.45%, 0.77%, 7.1, 0.90 g, 0.72 g, 129.2 g and 275 µʃ/cm in the same order. The implications of this results is that removal of vegetation contributes to the release of carbon into the atmosphere which increases atmospheric heat, alkalinity of soil, loss of soil nutrients and also could pose limits to the survival of plant growth and also susceptibility of soil to surface wash. Thus, it is recommended that effort should be made to checkmate the removal of vegetation and if unavoidable, relevant policies should be put in place for edge development and its maintenance and also, reforestation steps as remedies to ensure sustainable environment.

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Leachate seepages into groundwater aquifer from solid waste dumpsites is likely to release toxic pollutants in groundwater which are hazardous to human health and local ecosystem. A study was conducted on the Physico-chemical parameters of dumpsite leachate and surrounding groundwater from Awotan Solid Waste Dumpsite, in Ibadan, Oyo State. The study was aimed at assessing the impact of the leachate from the dumpsite. The physicochemical analyses of the water samples were carried by standard analytical methods. The results obtained were compared with the WHO (World Health Organization) permissible limit of those parameters in drinking water. The Physico-chemical values obtained for the dumpsite leachate were generally higher than those of groundwater samples, suggesting that a source of contamination could be from the dumpsite leachate. The pH of groundwater samples ranged between 5.03 to 6.94, indicating that the groundwater was acidic. Results of Physico-chemical parameters of dumpsite leachate for Cl-, NO3, TH, Alk, BOD, COD exceeded the WHO limits for drinking water. The BOD and COD of dumpsite leachate and groundwater samples exceeded the WHO limits and hence not safe for drinking. The concentration of Cl- and TH in the groundwater closer to the dumpsite were higher than WHO permissible limits for drinking water. Also, concentrations of the analyzed parameters decreased with increasing distance from the dumpsite, thus implicating leachate seepage from the dumpsite into the groundwater. It is therefore recommended that dumpsites be located away from the human settlements to avoid drinking water contamination and local ecosystem & biodiversity degradation.