CASPER: A modelling framework to link mineral carbonation with the turnover of organic matter in soil

Kolosz, B. W.; Sohi, S. P.; Manning, D. A.C.

Abstract

Rapid formation of stable soil carbonates offers a potential biologically-mediated strategy for removing atmospheric CO 2 and forms a part of the negative emissions debate in a bid to maintain global temperatures of 1.5 °C. Microbial respiration in soil and respiration by plant roots leads to high partial pressure of CO 2 below ground. Given adequate supply of calcium in soil solution the sequestration of C into the mineral calcite (CaCO 3 ) can occur at rapid rates. We have coupled an established soil C model RothC to a simplified geochemical model so that this strategy can be explored and assessed by simulation. The combined model CASPER partitions CO 2 respired belowground into soil solution as HCO 3− and simulates its reaction with Ca 2+ based on a particular dissolution rate for Ca-bearing minerals, with precipitation of calcite into soil pores as a consequence. Typical model output matches observed field rates of calcite accumulation over 5 years, namely 81 t ha −1 , with 19 t CO 2 ha −1 sequestered into the soil.

Citation

Kolosz, B. W., Sohi, S. P., & Manning, D. A. (2019). CASPER: A modelling framework to link mineral carbonation with the turnover of organic matter in soil. Computers & geosciences, 124, 58-71. https://doi.org/10.1016/j.cageo.2018.12.012

• Journal Article Type: Article
• Acceptance Date: Dec 23, 2018
• Online Publication Date: Jan 5, 2019
• Publication Date: Mar 1, 2019
• Deposit Date: Aug 3, 2024
• Publicly Available Date: Aug 13, 2024
• Journal: Computers and Geosciences
• Print ISSN: 0098-3004
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 124
• Pages: 58-71
• DOI: https://doi.org/10.1016/j.cageo.2018.12.012
• Keywords: Soil inorganic carbon; Carbon capture; Soil carbon modelling; Mineral weathering
• Public URL: https://hull-repository.worktribe.com/output/4057313