Can Green Scenarios Improve Water Ecosystem Services and Mitigate the Effects of Climate Change? A Case Study in a...

Ecological restoration is increasingly recognized as a key strategy to enhance ecosystem services and mitigate climate change impacts. However, there is limited understanding of whether spatially prioritized restoration areas remain effective under future climate and land-use changes. This study evaluates the combined effects of climate scenarios (RCP 4.5 and RCP 8.5 for 2040-2069 and 2070-2099) and land-use and land-cover (LULC) scenarios (economic, trend, and green) on water ecosystem services (WES) in a river basin in southeastern Brazil. Climate and biophysical models from the InVEST suite were used to simulate sediment export and retention (erosion control), total nitrogen and phosphorus export and retention (water purification), and quickflow and baseflow (water supply). The green scenario assumes the restoration of areas previously identified as spatial priorities in a published study based on a multicriteria analysis of WES, in addition to legally protected areas such as riparian buffers and legal reserves established by the Brazilian Forest Code. Results indicate that climate change primarily affected water supply services, whereas LULC changes exerted stronger effects on erosion control and water purification. Targeted restoration of priority and legally protected areas reduced sediment and nutrient exports and partially buffered climate change impacts on water supply. The novelty of this study lies in testing the robustness of restoration areas prioritized under current conditions by evaluating their effectiveness across future climate and land-use scenarios, rather than defining restoration areas directly within the scenario modeling process.