Appraising Forest Degradation Dynamics (1988-2018) in Umfakarin Natural Forest Reserve, Sudan, Using Multi-Temporal Landsat Imagery

Abstract

Sudan, recognized as a forest degradation and deforestation hotspot, has experienced significant forest loss in recent decades. The Umfakarin Natural Forest Reserve (UNFR) is undergoing rapid forest degradation driven by increasing human land-use pressure within a conflict-affected dryland environment. This study assessed long-term land use/land cover dynamics (LULC) and mapped forest degradation in the UNFR. Landsat satellite imagery from 1988, 2002, and 2018 were analyzed using maximum-likelihood supervised classification, transition matrix analysis, and supported by GNSS field-based verification. The classification results revealed marked LULC changes over the study periods, where tree cover reached its peak in 2002 at 32.13%, compared to 19.89% in 1988 and the marked decline by 18.43% in 2018, indicating fluctuating forest conditions. Mixed vegetation increased sharply by 2018 (22.54%) relative to 1988 (16.08%) and 2002 (5.43%), while agricultural land expanded significantly in 2018 (31.96%), exceeding levels observed in 1988 and 2002. Bare land showed a gradual decrease throughout the study period. Matrix analysis revealed rapid transitions across all LULC categories. Forest degradation in UNFR was primarily driven by illegal tree cutting, agricultural expansion, overgrazing, and settlement growth, remaining forest patches are increasingly fragmented and confined to interior areas and seasonal watercourses, indicating progressive forest degradation. Ineffective protection and management strategies have failed to prevent forest loss. This study provides the first spatially explicit, long-term assessment of forest degradation patterns within UNFR and demonstrates the effectiveness of integrating remote sensing and field data for monitoring dryland forests under socio-political and environmental stress. The study emphasizes the urgent need for effective conservation measures, the promotion of alternative livelihoods, formal delineation of reserve boundaries, and the active involvement of local communities to achieve long-term sustainability.