Increased yield and CO 2 sequestration potential with the C 4 cereal Sorghum bicolor cultivated in basaltic rock dust‐amended agricultural soil

作者：Mike Kelland, Peter Wade, Amy L. Lewis, Lyla L. Taylor, Binoy Sarkar, M. Grace Andrews, Mark R. Lomas, T. E. Anne Cotton, Simon J. Kemp, Rachael H. James, Christopher R. Pearce, Susan E. Hartley, Mark E. Hodson, Jonathan R. Leake, Steven A. Banwart, David J. Beerling · 发表于：Global Change Biology · 年份：2020 · DOI：10.1111/gcb.15089 · 被引用次数：284 · 研究领域：CO2 Sequestration and Geologic Interactions、Clay minerals and soil interactions、Geochemistry and Elemental Analysis

Abstract Land‐based enhanced rock weathering (ERW) is a biogeochemical carbon dioxide removal (CDR) strategy aiming to accelerate natural geological processes of carbon sequestration through application of crushed silicate rocks, such as basalt, to croplands and forested landscapes. However, the efficacy of the approach when undertaken with basalt, and its potential co‐benefits for agriculture, require experimental and field evaluation. Here we report that amending a UK clay‐loam agricultural soil with a high loading (10 kg/m 2 ) of relatively coarse‐grained crushed basalt significantly increased the yield (21 ± 9.4%, SE ) of the important C 4 cereal Sorghum bicolor under controlled environmental conditions, without accumulation of potentially toxic trace elements in the seeds. Yield increases resulted from the basalt treatment after 120 days without P‐ and K‐fertilizer addition. Shoot silicon concentrations also increased significantly (26 ± 5.4%, SE ), with potential benefits for crop resistance to biotic and abiotic stress. Elemental budgets indicate substantial release of base cations important for inorganic carbon removal and their accumulation mainly in the soil exchangeable pools. Geochemical reactive transport modelling, constrained by elemental budgets, indicated CO 2 sequestration rates of 2–4 t CO 2 /ha, 1–5 years after a single application of basaltic rock dust, including via newly formed soil carbonate minerals whose long‐term fate requires assessment through fie...