Forest modulation in enhanced olivine weathering: Insights fromMulti-Year Forest Trials and Global Scalability

Enhanced Silicate Weathering (ESW) using olivine is a promising Carbon Dioxide Removal (CDR) technology, yet the influence of forest type on its efficiency remains poorly understood. This study presents results from a 897-day field experiment comparing olivine (194 t ha ^-1 ) dissolution across grassland, coniferous, and broadleaf forest. By coupling high-resolution runoff chemistry with vertical hydrologic monitoring, we demonstrate that vegetation type dictates carbon sequestration efficiency. Our field trial reveals that the broadleaf forest achieves the highest CDR rate of 377.24 kg ha ^-1 y ^-1, which is 2.2 times higher than the 168.10 kg ha ^-1 y ^-1 of the coniferous forest and over 10 times that of 35.29 kg ha ^-1 y ^-1 of the grassland. Owing to the broadleaf forest has 1.74 times higher belowground biomass than a coniferous forest, root-derived organic acids may contribute to mineral dissolution. Scaling these findings via a 0.05° global model, we identify tropical broadleaf forests as primeESW hotspots, capable of removing up to 3.77 t ha ^-1 y ^-1,  higher than 1.16 t ha ^-1 y ^-1 of cropland.