TY - JOUR

T1 - Microbial and mineral interactions decouple litter quality from soil organic matter formation

AU - Elias, Dafydd M O

AU - Mason, Kelly E

AU - Goodall, Tim

AU - Taylor, Ashley

AU - Zhao, Pengzhi

AU - Otero-Fariña, Alba

AU - Chen, Hongmei

AU - Peacock, Caroline L

AU - Ostle, Nicholas J

AU - Griffiths, Robert I.

AU - Chapman, Pippa J

AU - Holden, Joseph

AU - Banwart, Steve

AU - McNamara, Niall P

AU - Whitaker, Jeanette

N1 - © 2024. The Author(s).

PY - 2024/11/20

Y1 - 2024/11/20

N2 - Current understanding of soil carbon dynamics suggests that plant litter quality and soil mineralogy control the formation of mineral-associated soil organic carbon (SOC). Due to more efficient microbial anabolism, high-quality litter may produce more microbial residues for stabilisation on mineral surfaces. To test these fundamental concepts, we manipulate soil mineralogy using pristine minerals, characterise microbial communities and use stable isotopes to measure decomposition of low- and high-quality litter and mineral stabilisation of litter-C. We find that high-quality litter leads to less (not more) efficient formation of mineral-associated SOC due to soil microbial community shifts which lower carbon use efficiency. Low-quality litter enhances loss of pre-existing SOC resulting in no effect of litter quality on total mineral-associated SOC. However, mineral-associated SOC formation is primarily controlled by soil mineralogy. These findings refute the hypothesis that high-quality plant litters form mineral-associated SOC most efficiently and advance our understanding of how mineralogy and litter-microbial interactions regulate SOC formation.

AB - Current understanding of soil carbon dynamics suggests that plant litter quality and soil mineralogy control the formation of mineral-associated soil organic carbon (SOC). Due to more efficient microbial anabolism, high-quality litter may produce more microbial residues for stabilisation on mineral surfaces. To test these fundamental concepts, we manipulate soil mineralogy using pristine minerals, characterise microbial communities and use stable isotopes to measure decomposition of low- and high-quality litter and mineral stabilisation of litter-C. We find that high-quality litter leads to less (not more) efficient formation of mineral-associated SOC due to soil microbial community shifts which lower carbon use efficiency. Low-quality litter enhances loss of pre-existing SOC resulting in no effect of litter quality on total mineral-associated SOC. However, mineral-associated SOC formation is primarily controlled by soil mineralogy. These findings refute the hypothesis that high-quality plant litters form mineral-associated SOC most efficiently and advance our understanding of how mineralogy and litter-microbial interactions regulate SOC formation.

U2 - 10.1038/s41467-024-54446-0

DO - 10.1038/s41467-024-54446-0

M3 - Article

C2 - 39567513

VL - 15

SP - 10063

JO - Nature Communications

JF - Nature Communications

SN - 2041-1723

IS - 1

ER -