A decision support system for evaluating fallowing strategy: conserving water and supporting agricultural economics in the Lower Rio Grande, Southern New Mexico through community-engaged system dynamics modeling

Water sustainability in the Lower Rio Grande region of southern New Mexico faces mounting challenges, including growing agricultural and municipal demands, uncertain policy directives, and prolonged drought conditions. Fallowing—temporarily taking land out of production—has been proposed as a strategy to conserve water, but its long-term effectiveness for sustaining both water resources and the agricultural economy remains unclear. This study builds on existing, previously published System Dynamics (SD) models, extending it through the integration of newly collected qualitative data to implement fallowing strategy and the development of a stakeholder-oriented decision support interface. The tool integrates SD modeling with social science insights derived from 49 semi-structured ethnographic interviews with local farmers to ensure relevance and usability. The SD model includes seven interconnected modules—hydrology, water use, agricultural and non-agricultural production, population, labor, and wages—along with fallowing-specific variables. The model incorporates hydro-agro-economic data for 205 variables, enabling simulation of feedback loops across water systems, economic activities, and land use decisions. Key DSS features include the ability to evaluate scenarios related to water rights, cover cropping, irrigation efficiency, mixed surface and groundwater use, crop rotation, and fallowing schedules. The DSS allows users to input specific farm-level information and visualize the long-term impacts of fallowing strategy on water availability and agricultural outcomes. Through an interactive interface, the tool aims to support data-driven decision-making among farmers, policymakers, and water managers. By combining scientific modeling with community engagement, this research contributes a practical framework for promoting sustainable water management and resilient agricultural systems in arid regions.