Future Land-use Changes in the transboundary Sio-Malaba-Malakisi Basin
of East Africa: Simulations using the CLUE-S model and Classified
Satellite Land Cover Datasets
Abstract
A comprehensive undertanding of land-use/cover(LUC) change processes,
their trends and future trajectories is essential for the development of
sustainable land-use management plans. While contemporay tools can today
be employed to monitor historical land-cover changes, prediction of
future change trajectories in most rural agro-ecological landscapes
remains a challenge. This study evaluated potential LUC changes in the
transboundary Sio-Malaba-Malakisi River Basin of Kenya and Uganda for
the period 2017-2047. The land use change drivers were obtained through
a rigorous fieldwork procedure and the Logistic Regression Model (LGM)
to establish key factors for the simulation. The CLUE-S model was
subsequently adapted to explore future LUC change trajectories under
different scenarios. The model was validated using historical land cover
maps for the period of 2008 and 2017, producing overall accuracy result
of 85.7% and a Kappa coefficient of 0.78. The spatial distribution of
vegetation cover types could be explained partially by proximate factors
like soil cation exchange capacity, soil organic carbon and soil pH. On
the other hand, built-up areas were mainly influenced by population
density. Under the afforestation scenario, areas under forest cover
expanded further occupying 54.7% of the basin. Conversely, under the
intense agriculture scenario, cropland and pasture cover types occupied
78% of the basin. However, in a scenario where natural forest and
wetlands were protected, cropland and pasture only expanded by 74%. The
study successfully outlined proximate land cover change drivers,
including potential future changes and could be used to support the
development of sustainable long-term transboundary land-use plans and
policy.