Modelling of land-use/cover change trajectories in a transboundary catchment of the Sio-Malaba-Malakisi Region in East Africa using the CLUE-s model

Abstract

A comprehensive undertanding of land-use change processes and their future trajectories is essential for the development of land-use management plans required for conservation of ecological resources. In East Africa, however, there is still limited information on historical, current and future land cover change trends within the vulnerable watersheds. In such data constrained areas, a few studies have adapted spatial models, employing historical land cover change trends derived from satellite remote sensing to provide the requisite landscape metrics for ecological modelling and management. In this study, the ensemble Conversion of Land Use and its Effects at Small regional extent (CLUE-s) model was used to model potential land-use/cover change trajectories in the transboundary Sio-Malaba-Malakisi Watershed of Kenya and Uganda. Historical change trends were obtained from consistently classified land cover datasets. The model parameters, which included climatic, biophysical and human factors were estimated from physical datasets in a Geographical information System (GIS). Two scenarios that represented options for agricultural expansion (Scenarion I), and land reclamation (Scenarion II) were investigated for the period between 2027 and 2047 to support ongoing regional inititiaves towards ecological resource conservation and watershed management across the transboundary region. From the results, Scenario I indicated an increase in the cropland area by 24%, covering approximately 62% of the whole basin area by 2047. A Scenario II indicated a 30% increase in forest cover, indicating an improvement in forest recovery and restoration of ecosystem area. The results obtained can be used to support baseline studies on the management of the transboundary region with varied country-management options.