Kukla et al. (2025): Swapping carbonate for silicate in agricultural enhanced rock weathering
Tyler Kukla, Yoshiki Kanzaki, Freya Chay, Noah Planavsky, Chris Reinhard, IN: CDRXiv, https://doi.org/10.70212/cdrxiv.2025304.v1
Enhanced rock weathering with crushed silicates is often considered as an alternative to agricultural liming for soil pH management and carbon dioxide removal. But swapping carbonates for silicates does not guarantee better carbon removal outcomes. Carbonates weather rapidly, and recent work has found that they can remove more carbon than fast-reacting silicates in some environments. On the other hand, carbonate dissolution can mobilize fossil carbon and potentially lead to carbon emissions, depending on the spatial and temporal boundaries of the system. Here, the authors use a one-dimensional reactive transport model, SCEPTER, to analyze the conditions where carbonate weathering breaks even with basalt — a common silicate rock used in enhanced weathering — from an end-to-end carbon removal perspective.