Blueing green water from forests as strategy to cope with climate change in water scarce regions: The case of the Catalan river basin District

Abstract

Water scarcity in Mediterranean basins is a critical concern exacerbated by climate change and afforestation of abandoned lands. This study addresses the impact of forest management on water availability, specifically blue water, at a regional scale. Utilizing the SWAT + model, we assess water yield increases resulting from various forest thinning scenarios (light, moderate, heavy) and compare benefits to costs. Our approach incorporates site-specific marginal values of water yield, accounting for urban water supply abstractions. The findings reveal the efficacy of hydrological-oriented forest management in alleviating water scarcity. Thinning intensity positively correlates with water yield, with coniferous forests exhibiting the greatest response and deciduous forests the least. Emphasizing blue water enhancement as a significant co-benefit in forest management planning, our study underscores the economic advantages. Particularly valuable in certain areas, this approach can offset a substantial portion of associated costs. Spatially explicit results enable optimal resource allocation, facilitating efficient planning and prioritization of intervention areas for successful hydrological-oriented strategies. In conclusion, our study not only highlights the economic benefits of forest management in enhancing water availability but also offers actionable insights for sustainable and effective hydrological-oriented planning amid escalating water scarcity

Xavier Garcia acknowledges funding from the European Union Horizon 2020 project MERLIN (H2020-LC-GD-2020-3:101036337). Laia Estrada acknowledges funding from the Secretariat of Universities and Research of Generalitat de Catalunya and the European Social Fund for her FI fellowship (2023 FI-2 00168). Authors acknowledge the support from the Economy and Knowledge Department of the Catalan Government through Consolidated Research Groups (ICRA-ENV 2021 SGR 01282), as well as from the CERCA program

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