Mapping the Impacts of Land Cover Change on Ecosystem Services in Bugesera District, Rwanda

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This study investigates the impacts of land use and land cover (LULC) changes on ecosystem services in Bugesera District, Rwanda, a region facing rapid urbanisation, agricultural expansion, and infrastructure development, such as the Bugesera International Airport. Forests in Bugesera are vital for carbon sequestration, biodiversity conservation and water regulation, yet they are increasingly threatened by anthropogenic pressures, leading to habitat fragmentation, biodiversity loss and hydrological disruptions. Globally and regionally, LULC transformations driven by population growth from 4.4 billion in 1980 to over 8 billion by the mid-2020s have exacerbated these issues, as seen in sub-Saharan Africa, where weak governance and urban sprawl have diminished ecosystem service values (ESVs). Locally, Rwanda's high population density (over 500 people per km²) and projected urban growth to 35% by 2050 intensify these challenges, underscoring the need for balanced development aligned with Sustainable Development Goals (SDGs) 11, 13, and 15. The general objective is to analyse LULC dynamics and their effects on ecosystem services using remote sensing data from 2004, 2014, and 2024. Specific objectives include assessing spatiotemporal LULC patterns, evaluating impacts on carbon sequestration, water regulation, and biodiversity, and identifying priority areas for sustainable land management. Methodologically, a mixed-methods approach was employed, integrating quantitative remote sensing with qualitative document reviews. Multi-temporal satellite imagery from Landsat and Sentinel-2 was sourced from USGS Earth Explorer, with administrative boundaries from the National Land Authority. Preprocessing involved radiometric and atmospheric corrections (DOS/FLAASH), geometric alignment using ground control points and cloud masking using Fmask. Supervised classification used Random Forest algorithms in Google Earth Engine and ArcGIS Pro, supplemented by NDVI and NDWI indices for 2016, 2020, and 2024 to evaluate vegetation health and water dynamics. Accuracy assessment incorporated confusion matrices, yielding overall accuracies of 88.86% (2004), 86.45% (2014) and 92.40% (2024), with Kappa coefficients of 0.87, 0.85 and 0.92, respectively. Change detection analysed post-classification comparisons and index differencing, while results were visualised through thematic maps, area statistics and hotspot overlays. Analysis revealed significant forest degradation, with coverage declining sharply from 840.59 km² in 2004 to 221.85 km² in 2024, primarily due to urban and agricultural encroachment. This led to reduced carbon storage, biodiversity erosion through habitat isolation, and altered hydrological cycles, increasing flood risks and groundwater depletion. NDVI trends indicated vegetation loss, while NDWI showed disrupted water regulation. In conclusion, the study highlights trade-offs between development and sustainability, emphasising Bugesera's vulnerability. Recommendations include integrated land management strategies, such as reforestation initiatives, policy reforms for land zoning and community-based conservation to enhance resilience. These evidence-based measures support Rwanda's Vision 2050 and global frameworks, promoting ecological restoration while fostering socio-economic growth.

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