Fungi enhance microbial carbon retention in high Arctic fjord sediment

Abstract

Fungi serve as critical biological carbon storage reservoirs in soil ecosystems, but whether this fungal trait is also important for marine sediment carbon storage processes is poorly understood. Here, we quantify for the first time assimilation of dissolved free amino acids by fungi in marine sediments from a high Arctic fjord and show that a distinct community of marine fungi promoted the stabilization of assimilated carbon via a relatively high metabolic efficiency. This corresponded to higher in situ ratios of fungi:prokaryote biomass in the fjord benthos, indicating efficient fungal metabolism promotes increased retention of microbial biomass at the seafloor. Quantitative stable isotope probing linked this efficient assimilation of amino acids to more than 80 fungal taxa in the fjord sediments, primarily associated with aquatic hyphomycetes. An efficient assimilation of amino acids is shown here to be a trait of marine fungi that plays a role in retaining labile dissolved organic matter as microbial biomass in Arctic fjord benthic ecosystems, hotspots for carbon sequestration that are currently experiencing rapid change due to climate warming. Our results indicate that fungal metabolism and biomass in marine sediment should be considered as an important contributor to seafloor carbon storage.

Increasing precipitation reshapes alpine plant–microbial nutrient partitioning and enhances ecosystem carbon and nitrogen retention
Qingzhou Zhao, David A Wardle, Grégoire T Freschet +3
Journal of Ecology9 Sep 2026Peer-reviewedCC BY 4.0Full textEcology Environmental science & pollutionHAL
Organic-mineral amendments enhance soil carbon accumulation and rice biomass in coastal salinized soil by regulating fungal necromass carbon and microbial communities
Ali Raza, Zhuoting He, Jingjie Zhou +9
Frontiers in Plant Science4 Nov 2026Peer-reviewedCC BY 4.0Plant biologyFrontiersCrossref
Depth-Resolved Microbial Community Structure and Phosphorus Deficiency Across a 34-cm Mat-Sediment Core in Poza Roja 2, Cuatrocienegas
A. Gonzalez-Sanchez, G. Ibarra-Arzave, A. Paniagua-Vargas +2
bioRxiv4 Oct 2026PreprintCC BYFull textMicrobiologybioRxiv
Diversity and connectivity of microbial eukaryotes in High Arctic terrestrial and aquatic ecosystems.
P M Hooper, W F Vincent, C Girard +3
FEMS microbiology ecology30 Oct 2026Peer-reviewedCC BYFull textEcologyEurope PMCPMC
Environmental Drivers of Sediment Microbial Community Structure Across Restored, Altered, and Reference Mangroves in Las Calderas Bay, Dominican Republic
H. B. Lopez-Chevalier, A. N. Avelino Perez, J. E. Suriel Jaime +2
bioRxiv3 Oct 2026PreprintCC BY-NC-NDFull textMicrobiologybioRxiv

Cite

BibTeX RIS

BibTeX

@article{trejosespeleta2026fungi,
  title = {{Fungi enhance microbial carbon retention in high Arctic fjord sediment}},
  author = {Juan Carlos Trejos-Espeleta and James A Bradley and Ömer K Coskun and Laura M Wehrmann and Gonzalo V Gomez-Saez and William D Orsi},
  journal = {PLoS Biology},
  year = {2026},
  month = nov,
  doi = {10.1371/journal.pbio.3003783},
  url = {https://hal.science/hal-05856683v1},
  note = {CC BY 4.0},
}

RIS

TY  - JOUR
TI  - Fungi enhance microbial carbon retention in high Arctic fjord sediment
AU  - Juan Carlos Trejos-Espeleta
AU  - James A Bradley
AU  - Ömer K Coskun
AU  - Laura M Wehrmann
AU  - Gonzalo V Gomez-Saez
AU  - William D Orsi
PY  - 2026
DA  - 2026/11/09
JO  - PLoS Biology
DO  - 10.1371/journal.pbio.3003783
UR  - https://hal.science/hal-05856683v1
AB  - Fungi serve as critical biological carbon storage reservoirs in soil ecosystems, but whether this fungal trait is also important for marine sediment carbon storage processes is poorly understood. Here, we quantify for the first time assimilation of dissolved free amino acids by fungi in marine sediments from a high Arctic fjord and show that a distinct community of marine fungi promoted the stabilization of assimilated carbon via a relatively high metabolic efficiency. This corresponded to higher in situ ratios of fungi:prokaryote biomass in the fjord benthos, indicating efficient fungal metabolism promotes increased retention of microbial biomass at the seafloor. Quantitative stable isotope probing linked this efficient assimilation of amino acids to more than 80 fungal taxa in the fjord sediments, primarily associated with aquatic hyphomycetes. An efficient assimilation of amino acids is shown here to be a trait of marine fungi that plays a role in retaining labile dissolved organic matter as microbial biomass in Arctic fjord benthic ecosystems, hotspots for carbon sequestration that are currently experiencing rapid change due to climate warming. Our results indicate that fungal metabolism and biomass in marine sediment should be considered as an important contributor to seafloor carbon storage.
SN  - 1544-9173
SN  - 1545-7885
ER  -

Abstract

Related

Cite