GIS-Based Evaluation of Actual and Potential Land Suitability for Potato (Solanum tuberosum L.) Cultivation in the Post-Eruption Landscape of Mount Sinabung, Indonesia

Abstract

Potato (Solanum tuberosum L.) is a high-value horticultural crop whose productivity depends strongly on land suitability, particularly in volcanic regions where repeated eruptions alter soil properties and landscape characteristics. Evaluating land suitability is therefore essential for identifying cultivation constraints and developing sustainable land management strategies. This study assessed the actual and potential land suitability for potato cultivation in the post-eruption area of Mount Sinabung, North Sumatra, Indonesia, using a Geographic Information System (GIS)-based land evaluation approach integrated with the FAO matching framework. Land Mapping Units (LMUs) were delineated through the overlay of soil type, elevation, and slope maps, followed by field surveys and laboratory analyses of soil physical and chemical properties. Thirteen LMUs were identified, with LMU 1 (Sigarang-garang Village) and LMU 2 (Sukanalu Village) representing the eruption-affected agricultural areas. Under current conditions, LMU 1 was classified as Not Suitable (N) because of severe erosion hazards, whereas LMU 2 was classified as Marginally Suitable (S3), primarily constrained by temperature and nutrient retention. Following the implementation of feasible land improvement measures, including soil conservation, liming, and organic matter application, the potential suitability of LMU 1 improved to S3, while LMU 2 remained S3 due to persistent climatic and land preparation constraints. The findings indicate that erosion hazard and nutrient retention are manageable limiting factors, whereas temperature and topographic conditions remain relatively permanent constraints. This study demonstrates the value of integrating GIS, field observations, laboratory analyses, and FAO land evaluation for supporting evidence-based agricultural planning and sustainable potato production in volcanic post-eruption landscapes.