Water-land-food-human health nexus in bioenergy supply chain optimization under climatic constraints

This study presents an integrated model that addresses the complex interplay between water, land, food, and human health for the optimal design of a BioEnergy Supply Chain (BESC), with a focus on future climate challenges. The model is designed to balance key objectives such as minimizing economic costs, reducing human health impacts, and optimizing water use. By employing a weighted-sum approach, the model identifies the best land allocation for various crops and the most efficient biofuel production pathways. Climate change impacts are analyzed by downscaling projections from the Hadley Centre Global Environmental Model (HADGEM) for Qazvin Province, Iran, using two climate scenarios: SSP5-8.5 (high emissions) and SSP2-4.5 (moderate emissions). The results indicate that water use for crop cultivation increases significantly under SSP5-8.5, by 14.31 % and 132.97 %, compared to SSP2-4.5 and a business-as-usual (BAU) scenario, respectively. Economic costs under SSP5-8.5 are found to be 2.5 and 4.1 times higher than those under SSP2-4.5 and BAU, while the avoided human health impacts decrease. These results reveal critical trade-offs between financial investment and human health outcomes under different climate scenarios. The optimal bioenergy pathways include bioethanol from corn and sugar beet, biogas from wheat, biohydrogen from corn, and jet fuel from wheat. The study underscores the necessity of integrating climate change constraints into BESC optimization models, as these significantly affect both economic and health outcomes. The findings provide important insights for policymakers, helping them develop strategies that balance multiple objectives and adapt to the impacts of climate change on bioenergy production and resource allocation.