The land-water nexus of biofuel production in Brazil: Analysis of synergies and trade-offs using a multiregional input-output model

Biofuels play a critical role in the Paris Agreement to help achieve climate change mitigation targets. However, a significant increase in production of biofuels might potentially be realized at the expense of overusing natural resources, particularly land and water. Understanding the tradeoffs between the impacts on land and water arises as a critical issue in the development of biofuels. This energy-water-land nexus might be particularly important for Brazil, which currently is the world's second largest producer and the largest exporter of biofuels. Furthermore, Brazil itself has set up its own Intended Nationally Determined Contribution agenda with a significant growth of biofuel production (18%) by 2030. Most studies on environmental impacts of biofuel production have either focused on land use or water use, but very few studies assessed both. Using an environmentally extended multiregional input-output (MRIO) approach, this study analyzes the current water-land nexus of bioenergy production in Brazil by quantifying the distribution of tradeoffs and synergies between land and water use for bioethanol production and its environmental consequences across Brazilian states. Our results show a clear tradeoff of water and land impacts and significant differences between irrigated and rainfed ethanol production. When including water and land scarcity in the analysis, the results are significantly different, uncovering very different tradeoffs and synergies between bioethanol producer and consumer states that could inform the expansion of bioenergy in Brazil. Compared to other crops, sugarcane has a higher comparative advantage relative to land than to water