The elevated atmospheric CO2 concentrations that cause global warming are expected to increase the amount of organic compounds secreted by plant roots into the soil. CO2 is sequestered by plants and than it is secreted into the local soil by the roots along with other organic compounds. Researches determined that this process normally promotes loss of carbon through the soil. This short process is called priming and it is where there is microbial mineralization of the input carbon. Other studies have shown that climate change increases root secretion, which increases microbial access to compounds, causing an acceleration in carbon loss. The global increases of atmospheric CO2 change the amount and composition of the CO2 and organic compounds released into the soil. elevated CO2 concentrations may also alter the composition of the compounds that are secreted by the roots with an increase in metal and organic matter.
“Our results provide new insights into the coupled biotic-abiotic mechanisms underlying the ‘priming’ phenomenon and challenge the assumption that mineral-associated carbon is protected from microbial cycling over millennial timescales”