Enhanced Rock Weathering Altered Soil Organic Carbon Fluxes in a Plant Trial

作者：Lucilla Boito, Laura Steinwidder, Jet Rijnders, Jesse Berwouts, Sarah Janse, Harun Niron, Jasper Roussard, Arthur Vienne, Sara Vicca · 发表于：Global Change Biology · 年份：2025 · DOI：10.1111/gcb.70373 · 被引用次数：14 · 研究领域：CO2 Sequestration and Geologic Interactions、Geology and Paleoclimatology Research、Geological and Geochemical Analysis

ABSTRACT Enhanced rock weathering (EW) is gaining attention as a promising carbon dioxide removal strategy, primarily due to its potential to sequester inorganic carbon through mineral dissolution. However, the broader biogeochemical implications of EW, particularly its effects on soil organic carbon (SOC) dynamics, as well as the role played by agriculturally relevant biota such as plants and earthworms, remain poorly understood. In a 15‐month mesocosm experiment with Zea mays , we investigated how EW with basalt influences soil CO 2 efflux (SCE; normalized for soil water content and temperature) and how this is modulated by plant and earthworm presence. Using δ 13 C‐CO 2 isotope tracing based on the C 3 –C 4 shift method, we partitioned normalized SCE into rhizosphere (root plus microbial respiration of rhizodeposits) and soil organic matter components. In the first growing season, basalt increased normalized SCE 2.8‐fold in planted mesocosms relative to planted controls, due to elevated rhizosphere respiration. In contrast, during the second growing season, basalt significantly decreased normalized SCE 16.5‐fold, but only in unplanted mesocosms. Mediation analysis revealed that basalt also indirectly influenced SCE via changes in soil water content, with the direction of this effect depending on plant presence and growing season. Basalt showed contrasting direct and indirect effects, highlighting the complexity of soil responses to silicate amendments, where multiple, some...