Publication

Abstract : Global climate change remains one of the most urgent challenges of the twenty-first century, with its adverse effects disproportionately impacting arid and semi-arid regions where limited resources and persistent water scarcity constrain agricultural development. Multi-criteria evaluation methods that combine the fuzzy analytical hierarchy process (AHP) and the technique for order preference by similarity to ideal solution (TOPSIS) with geospatial techniques have become essential for land suitability assessments that support climate-smart agricultural practices and policy decisions. This study assessed land suitability for rice, millet, and maize by integrating fuzzy-AHP and TOPSIS within a geospatial framework. Ten biophysical and climatic factors were converted into thematic layers in ArcGIS, weighted using fuzzy AHP, and integrated under the FAO land evaluation framework to produce multi-crop suitability maps. Spatial analysis revealed pronounced inter-district variability in agricultural potential. For rice, Manvi had the largest area of highly suitable land (79,312.46 ha), followed by Raichur (53,427.68 ha), while Devadurga had only 13,587.24 ha in this class, indicating greater climatic and soil constraints. Millet suitability was also highest in Manvi (63,412.36 ha), with Raichur (35,127.49 ha) and Devadurga (23,678.92 ha) showing moderate to marginal potential. Maize suitability showed a similar pattern, with Manvi covering 81,745.62 ha (41.5%) of highly suitable land and Devadurga having the most unsuitable area (44,310.65 ha). The assessment identified key biophysical and climatic constraints such as acidic soils (pH 4–5), low soil organic carbon (0–12 g/kg), and limited annual rainfall (440–670 mm), which collectively restrict agricultural potential. Validation with long-term yield records showed strong, statistically significant positive correlations for rice (r = 0.966, p < 0.05) and millet (r = 0.953, p < 0.05), confirming the robustness of the results. These findings provide a spatially explicit foundation for climate-smart interventions and strategic planning in semi-arid Karnataka, offering practical guidance for policymakers, planners, and farmers by identifying soil and climate constraints and informing crop allocation strategies to boost efficiency and productivity.