Short‐term hydromorphological and ecological responses of using woody structures for river restoration in a tailing‐impacted tropical river.

The article focuses on the implementation and evaluation of the ReNaturalize river restoration project in the Gualaxo do Norte River (GNR), southeastern Brazil, which was ecologically impacted by iron ore tailings from the 2015 Fundão Dam rupture. The project used 203 wooden structures, including large woody debris and vegetation bundles, installed over 1.8 km to restore hydrogeomorphological features and enhance habitat diversity, aiming to accelerate ecological recovery. After 14 months, the restored reaches showed increased hydraulic retention time, sediment accumulation, substrate heterogeneity, and significant improvements in benthic macroinvertebrate abundance and fish recruitment, abundance, and biomass compared to control reaches. The study concludes that this low-cost, innovative restoration technique effectively accelerates ecological resilience in tropical rivers affected by mining disasters and recommends its application in other impacted river systems.