Page 55 - CEGE Research and Contributions

Clay-carbon protection and release revealed through 4D imaging
Soil absorbs about 20% of anthropogenic carbon emissions annually and clay
in particular is a key carbon-capture material. Although sorption to clay is widely assumed to retard the microbial decomposition of soil organic matter, enhanced degradation of clay-associated organic carbon has been observed under certain conditions. The fate of the clay- protected carbon under future climate conditions is uncertain. Researchers observed clay-carbon dynamics within transparent clay micro-aggregates
using a new 4D imaging technology
and a customized microfluidic chip. It is demonstrated that clay-carbon protection is due to the quasi-irreversible sorption of high molecular-weight sugars within clay aggregates and to the exclusion
of bacteria from these aggregates.
This physically-protected carbon
can be enzymatically broken down
into fragments that are released into solution. Further, the research suggests improvements relevant to global soil carbon predictive models. [102]
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