Data for: CASPER: A modelling framework to link mineral carbonation with turnover of organic matter in soil
Microbial respiration in soil and respiration by plant roots leads to high partial pressure of CO2 below ground. Combined with adequate supply of calcium in soil solution the sequestration of C into the mineral calcite (calcium carbonate) can occur at greatly enhanced rates. Rapid formation of soil carbonates offers a potential biogenic strategy to remove and store atmospheric CO2. We have coupled an established soil C model RothC to a simplified geochemical model so that this strategy can be simulated and assessed. The combined model CASPER partitions CO2 respired belowground into soil solution as HCO3- and simulates its reaction with Ca2+; using dissolution rates for Ca-bearing minerals. Precipitation of calcite (into soil pores) is then modelled. In total, approximately 19 tonnes of CO2 per ha were sequestered into the soil by precipitation of calcium carbonate over 5 years, corresponding to an accumulation of approximately 81 tonnes of calcite (CaCO3).