Spatio-temporal Dynamics of Vegetation Cover and Flood Vulnerability in Uvira City of DRC (1990-2024)
Salomon Bwirabuciza Luhinzo *
Faculty of Sciences and Agricultural Sciences, Sharon University of Bunia, P.O.Box.304, Bunia, Democratic Republic of Congo and Centre for Research in Natural and Environmental Sciences (CRNSE), University of Burundi, Faculty of Sciences, P.O.Box.2700, Bujumbura, Burundi.
Daniel Sefania
Department of Biology-Chemistry, Higher Pedagogical Institute of Uvira, PO Box 18, Uvira, Democratic Republic of Congo.
Mapenzi Kaluguto
Department of Biology-Chemistry, Higher Pedagogical Institute of Uvira, PO Box 18, Uvira, Democratic Republic of Congo.
Nehemiya Lampenzi
Department of Biology-Chemistry, Higher Pedagogical Institute of Uvira, PO Box 18, Uvira, Democratic Republic of Congo.
Mkambwa Elondano John
Department of Biology-Chemistry, Higher Pedagogical Institute of Uvira, PO Box 18, Uvira, Democratic Republic of Congo.
Penedimanja Pancrace
Department of Biology-Chemistry, Higher Pedagogical Institute of Uvira, PO Box 18, Uvira, Democratic Republic of Congo.
Dramani Lotse
Faculty of Development Sciences, Sharon University of Bunia, P.O.Box.304, Bunia, Democratic Republic of Congo.
Martin Nyogolo
Research Laboratory in Entrepreneurial Innovation and Sustainable development, Higher Institute of Rural Development of Uvira, P.O.Box.1760,Bujumbura, Burundi.
Benjamin Mukasani
Centre for Research in Natural and Environmental Sciences (CRNSE), University of Burundi, Faculty of Sciences, P.O.Box.2700, Bujumbura, Burundi, Research Laboratory in Entrepreneurial Innovation and Sustainable development, Higher Institute of Rural Development of Uvira, P.O.Box.1760,Bujumbura, Burundi and Faculty of Agricultural Sciences and Environment , University Notre Dame of Tanganyika, PO Box 18, Uvira, Democratic Republic of Congo.
Lambert Niyoyitungiye
Centre for Research in Natural and Environmental Sciences (CRNSE), University of Burundi, Faculty of Sciences, P.O.Box.2700, Bujumbura, Burundi and Department of Biology, Faculty of Sciences, University of Burundi, P.O.Box.2700, Bujumbura, Burundi.
*Author to whom correspondence should be addressed.
Abstract
Secondary African cities are increasingly trapped between rapid, unplanned urbanization and escalating climate-related hazards. Uvira (DRC), strategically located between the steep Mitumba Mountains and Lake Tanganyika, exemplifies this critical vulnerability.
Methods: This study investigate the 34-year (1990-2024) spatio-temporal interactions between vegetation dynamics and flood hazards using an integrated remote sensing and GIS approach. Multi-temporal Landsat and Sentinel-2 imagery were processed to derive NDVI and NDWI indices, coupled with Random Forest LULC classification (Kappa > 0.85) and Digital Elevation Model (DEM) analysis.
Results: findings quantify a profound ecological collapse, characterized by a 39.6% net reduction in vegetation cover and a sixfold increase in bare soils since 2010. This loss of green infrastructure have fundamentally altered the catchment;s hydrological response, as evidenced by a 7.8% expansion of water surface area (NDWI) in low-lying coastal zones. The topographic "funnel effect" of Uvira;s steep slopes, combined with the erosion of natural hydraulic resistance, have also transformed seasonal discharge into destructive flash floods. The study demonstrated that the "coastal squeeze";the convergence of rising lake levels and urban encroachment; has institutionalized flood risk as a structural component of the landscape. We argue for the urgent integration of Nature-based Solutions (NbS), specifically upstream reforestation and strict enforcement of non-aedificandi zones, to restore essential hydraulic regulation services and safeguard vulnerable populations.
Keywords: Spatio-temporal, dynamics, vegetation cover, flood vulnerability, Uvira City, DRC