AMHERST, Mass. – In what they believe is the first study of its kind, researchers led by postdoctoral researcher Luiz A. Domeignoz-Horta and senior author Kristen DeAngelis at the University of Massachusetts Amherst report that shifts in the diversity of soil microbial communities can change the soil’s ability to sequester carbon, where it usually helps to regulate climate.
They also found that the positive effect of diversity on carbon use efficiency – which plays a central role in that storage – is neutralized in dry conditions. Carbon use efficiency refers to the carbon assimilated into microbial products vs carbon lost to the atmosphere as CO2 and contributing to climate warming, DeAngelis explains. Among other benefits, soil carbon makes soil healthy by holding water and helping plants grow.
She and colleagues addressed these questions because they point out, “empirical evidence for the response of soil carbon cycling to the combined effects of warming, drought and diversity loss is scarce.”