Impact of Land-Use/Land-Cover Change on Drinking Water Ecosystem Services in Wami River Basin, Tanzania

Land-use/land-cover changes are considered the dominant form of anthropogenic pressure on the environment, causing changes in ecosystem service patterns and affecting water supply services. Using the spatial econometric technique, we analysed the impact of land-use/land-cover change on water ecosystem services for domestic use upstream and downstream of the Wami River Basin. The results in terms of land-use/land-cover classes during the study period (2011–2016) indicate that cultivated land showed maximum positive changes in both sub-catchments, while bushland and woodland showed maximum negative changes upstream and downstream. The results showed that bushland, woodland, cultivated land, and grassland were significantly correlated with water point characteristics in both sub-catchments. For functionality characteristics, a significant effect was observed in bushland and grassland upstream and downstream, respectively, while sufficient water was found in woodland upstream and grassland downstream. Moreover, bushland was observed to have a significant number of water points with poor quality of water upstream, and a substantial number of water points with good quality of water were found in grassland downstream. We found that all measured land-use/land-cover changes and water point characteristic correlations were statistically significant; therefore, we concluded that land-use/land-cover change affects the water ecosystem in the basin. These results could facilitate decision-making and development of related policies and might support finding sustainable strategies for water ecosystem services for domestic use.