Land Suitability Assessment for Coffee Cultivation in Nyamagabe District, Rwanda, Using GIS-Based Modelling

Sammanfattning

Land suitability assessments for coffee cultivation can support agroecological planning and contribute to food security and economic stability in many African regions. The study identifies land suitability for coffee cultivation in Nyamagabe, Rwanda, highlighting the significant influence of air temperature, rainfall, and elevation on coffee plantations. By comparing two spatial analysis results, the current suitable areas and projected suitability, the impact of climate change is evaluated. The suitability model incorporates climatic, edaphic, topographic, and socioeconomic variables, including annual mean temperature, annual rainfall, maximum temperature of warmest month, minimum temperature of coldest month, soil texture, pH, Cation Exchange Capacity (CEC), Soil Organic Matter (SOM), elevation, slope, aspect, distance to road, and to river. Data were standardized and weighted using the criteria for coffee cultivation. Geographic Information Systems (GIS), Analytic Hierarchy Process (AHP), and Remote Sensing (RS) were integrated into the study. Future climate projection (2041-2060) under CMIP6 scenarios (SSP3-7.0) were applied for suitability analysis. The findings suggested that in the future, climate change may reduce the suitability of some current coffee-growing areas, while optimal climatic conditions are projected to shift upslope within Nyamagabe District. In the region, the current potential suitable, sub-suitable, and unsuitable areas account for 35.8%, 35.3%, and 8.1%, respectively, while Nyungwe National Park accounts for 19.3% of the total area. Under the SSP3-7.0 scenario for the 2041-2060 period, suitable and sub-suitable zones are projected to increase by 2.7% and 5.7% respectively, when unsuitable areas are projected to decrease by 7.5 percentage points compared to current levels.