Quantitative multi-factor characterization of ecological vulnerability in the Mount Elgon ecosystem

Abstract:

Climate change continues to threaten agriculture-based economies, especially in developing nations. The synergistic combination of population growth, expansion of agricultural land and increase in resource extraction has changed the ecological landscape of East Africa, and thus, has modified land-atmosphere interactions and local climates. The Mount Elgon ecosystem, an important hydrological and socio-economic area in East Africa, exhibits significant landscape changes, driven by both natural factors (e.g. changes in precipitation) and human activities (e.g. vegetation-to-cropland conversion), therefore leading to more frequent natural disasters (frequent and extended droughts, floods, and landslides). Yet, the vulnerability of this ecosystem to future changes is least understood. The current study seeks to characterize ecological vulnerability for Mount Elgon using earth observation, topographic and socio-economic data. We apply a combination of spatial principal component analysis (SPCA) and analytical hierarchy process (AHP) to compute an ecological vulnerability index (EVI) for the study area by integrating natural, environmental, and socio-economic conditions. The final EVI is then categorized into four classes indicative of low, moderate, high, and extreme vulnerability. This analysis will highlight the differentiated environmental vulnerability levels in Mount Elgon, which can be used to identify target areas with limited resources where urgent policy actions should be employed. This is a necessary step towards simultaneously conserving the natural environment and improving livelihoods that depend on it.