Environmental Situation of an Agricultural Area in Akure, Nigeria, Based on Physico-Chemical Properties of Rainwater

Abstract

Acid rain still poses a global problem today, exerting many adverse effects on man, animal, and materials. As its research question, the present study tries to find out whether or not acid rains exist in Akure, Nigeria. For so doing, it determines physico-chemical properties of rain water samples, namely pH, temp, Electrical Conductivity (EC), TDS, acidity, SO₄^-, NO₂^-, Cl^-, and Free CO₂. According to the results, the pH ranged between 6.0 and 7.8, never falling below 5.6 which is an indication of acid rain. Also, the minimum EC was 3µS/cm and the maximum, 201µS/cm. Moreover, TDS was between 1 and 100mg/L, while Free CO₂had a mean of 23.00 and Standard Deviation of 6.16. The dominant ion was SO₄^- (10-11%), followed by NO₃^-, and Cl^-. Results from the first six months (July-December 2015) reveal slight correlations in the following: TDS with pH (0.532), EC and pH (0.501), Temp and Free CO₂ (0.59), whereas strong correlations have been recorded in the following parameters: Acidity with pH (0.71) and Temperature (0.69), NO₂^- with pH (0.96) and acidity (0.96), SO₄^- with temp (0.68) and NO₂^-(0.83), and finally Cl- with Free CO₂ (0.61), NO₂^-(0.73), and Cl- (0.65). It can be concluded that in the environment under this study there have been no acid rain within the period.