Rainfall trends and its implications on water resources management: a case study of Ogbomoso city in Nigeria

Abstract

A 37-year annual rainfall was collected from NIMET to study the trend of rainfall parameter and its implications on water resources management in the tropical city of Ogbomoso, Oyo State, Nigeria. The data was co-tested by both parametric and non-parametric statistical methods to determine the trend. The linear regression statistic and M-K, both, showed that rainfall trend in the study area is positive over the period with R2 of 0.001 while M-K showed positive trend at 0.05significance level. The results of the analysis implied that more rainwater was received in the city during the period under consideration. Thus, there was sustainable natural replenishment of both surface and subsurface water sources. The study further noted the possible negative effects of this finding including contamination of surface sources, destruction of life and properties through flooding including farmlands, human infrastructure and prevalence of diseases, among others. Thus, efforts should be made to ensure comprehensive water resource management. However, further research into the optimal utilization of the excess rainwater received in the area should be investigated.