Plant rhizodeposition: A key factor for soil organic matter formation in stable fractions.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33853771.
- Also identified by DOI 10.1126/sciadv.abd3176 and PMC identifier 8046368.
- Licence recorded as CC BY-NC.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Soil organic carbon formation remains poorly understood despite its importance for human livelihoods. Uncertainties remain for the relative contributions of aboveground, root, and rhizodeposition inputs to particulate (POC) and mineral-associated (MAOC) organic carbon fractions. Combining a novel framework with isotope tracer studies, we quantified POC and MAOC formation efficiencies (% of C-inputs incorporated into each fraction). We found that rhizodeposition inputs have the highest MAOC formation efficiency (46%) as compared to roots (9%) or aboveground inputs (7%). In addition, rhizodeposition unexpectedly reduced POC formation, likely because it increased decomposition rates of new POC. Conversely, root biomass inputs have the highest POC formation efficiency (19%). Therefore, rhizodeposition and roots appear to play opposite but complementary roles for building MAOC and POC fractions.