Nature-based solutions in mountain catchments reduce impact of anthropogenic climate change on drought streamflow

This study quantifies the effectiveness of Nature-based Solutions (NbS) in mitigating the impacts of anthropogenic climate change on drought streamflow. Invasive alien tree clearing, a widely applied NbS in South Africa, was found to reduce the impact of anthropogenic climate change on streamflow during the 2015-2017 Cape Town "Day Zero" drought. Anthropogenic climate change reduced streamflow by 12-29%, exceeding reductions in rainfall (7-15%) and reference evapotranspiration (1.7-2%). Clearing invasive alien trees could have ameliorated streamflow reductions by 3-16%, and preventing further spread avoided additional reductions of 10-27%. While effective, complete clearing couldn't fully offset the anthropogenic climate change impact, highlighting the need for integrated adaptation strategies.

Petra B. Holden, Alanna J. Rebelo, Piotr Wolski, Romaric C. Odoulami, Kamoru A. Lawal, Joyce Kimutai, Tiro Nkemelang, Mark G. New