Modelling optimal ligninolytic activity during plant litter decomposition

Sammanfattning

center dot A large fraction of plant litter comprises recalcitrant aromatic compounds (lignin and other phenolics). Quantifying the fate of aromatic compounds is difficult, because oxidative degradation of aromatic carbon (C) is a costly but necessary endeavor for microorganisms, and we do not know when gains from the decomposition of aromatic C outweigh energetic costs. center dot To evaluate these tradeoffs, we developed a litter decomposition model in which the aromatic C decomposition rate is optimized dynamically to maximize microbial growth for the given costs of maintaining ligninolytic activity. We tested model performance against > 200 litter decomposition datasets collected from published literature and assessed the effects of climate and litter chemistry on litter decomposition. center dot The model predicted a time-varying ligninolytic oxidation rate, which was used to calculate the lag time before the decomposition of aromatic C is initiated. Warmer conditions increased decomposition rates, shortened the lag time of aromatic C oxidation, and improved microbial C-use efficiency by decreasing the costs of oxidation. Moreover, a higher initial content of aromatic C promoted an earlier start of aromatic C decomposition under any climate. center dot With this contribution, we highlight the application of eco-evolutionary approaches based on optimized microbial life strategies as an alternative parametrization scheme for litter decomposition models.

Nyckelord

aromatic; eco-evolutionary dynamics; lignin; litter decomposition; metabolic tradeoff; optimal control

Publicerad i

New Phytologist
2024, volym: 243, nummer: 3, sidor: 866-880
Utgivare: WILEY

SLU författare

• Lindahl, Björn

  • Institutionen för mark och miljö, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Botanik
Markvetenskap

Publikationens identifierare

• DOI: https://doi.org/10.1111/nph.19572

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/128664