Wise decision support for land-use transitions in livestock-dominated regions: a recalibrable multi-objective sector model and policy sandbox, applied to Córdoba, Colombia

CONTEXT: Digital tools for agricultural planning typically optimize a single objective, yet land-use transitions in livestock-dominated regions of the Global South set economic welfare, climate, water, and land-use diversity against one another. For regional governments the binding constraint is often not modeling capacity but the translation of model output into choices that can be deliberated. OBJECTIVE: To develop an open, recalibrable decision-support system that lets departmental planners weigh these four-way trade-offs instead of receiving a single prescribed optimum. METHODS: A four-objective sector model jointly optimizes consumer-producer surplus, greenhouse-gas emissions including enteric methane, water footprint, and land-use diversity (Shannon entropy) across nine land uses including pasture, calibrated to observed 2018 allocations by positive mathematical programming. A web application solves the model live, in open-source software, for the objective weights and policy levers a planner sets. RESULTS AND CONCLUSIONS: In Córdoba, Colombia, the climate-water trade-off is governed by the livestock-crop boundary. The compromise cuts emissions 36.5% and total water use 17.9% at a 4.3% welfare cost, contracting pasture 48.5%, yet raises water use per hectare 18.0% under the water-accounting convention adopted; diversity rises from 2.63 to 4.48 effective land uses. A higher self-sufficiency floor locks in pasture and lowers attainable diversity, an unintended consequence of a food-security target. SIGNIFICANCE: Making land-use diversity an explicit objective and the objective weights a planner's explicit, revisable choice turns technical optimization into wise decision support. The system is a research prototype, recalibrable to other regions with this land-use structure. Funding: Bicentennial Doctoral Excellence Scholarship programme (Becas de Excelencia Doctoral del Bicentenario), with resources from the Science, Technology and Innovation Fund of the General Royalties System of Colombia (Sistema General de Regalías), administered by Universidad del Norte. Working paper. The record and its identifier are public; the files are under restricted access while a version of the paper is prepared for journal submission. Access to the files can be requested through this record.