Assessment of effects of deforestation on spring’s water production: A case study of Nuu/Mutaitho Hills Springs in Kitui County

Abstract

This study is focused on the assessment of the effects of deforestation on springs found in Nuu and Mutaitho hills in Kitui County. Deforestation is manifested by clearing of dry land forests on a massive scale. Springs in Nuu and Mutaitho hills originate from groundwater aquifers and are essentially formed on hillsides and valley bottoms that intersect groundwater flow at or below the local water table. The main objective of the study was to determine the main causes of decline in spring discharges in Nuu and Mutaitho Hills catchment. This was achieved through establishment of the relationship between spring discharges, rate of deforestation, and rainfall variability. The study also involved determination of the impacts of decreasing spring discharges and examination of the perceptions of the local communities on the causes of decline in spring discharges. The study methodology involved collection of data in the field using questionnaires and field based observations. Field data was supplemented with data that was obtained from archival sources e.g spring discharges and rainfall data. The data was analyzed using the Statistical Package for the Social Sciences (SPSS), Geographical Information system (GIS) and various statistical tools in Microsoft Excel package. The result of the study shows that annual rainfall is showing significant variation while the spring discharges over the years has been decreasing drastically. Springs discharge is decreasing at a rate of 30%. Rainfall variability in the study area has changed within the study time from 800mm/year to around 700mm/year. The LANDSAT data showed that the forest /vegetation cover has decreased by almost 40% as the forest in 1963 was at 10% and the current forest cover is about 6% within the study area. The main cause of the decrease of the forest cover from the study is mainly anthropogenic activities. The study recommends more awareness campaign focusing on conservation of the Nuu hills forests and enforcement of regulations focused on the protecting forest resources.