Highly stable active core microbiomes in Greenland cryoconite holes during the bare ice period

TY - JOUR

T1 - Highly stable active core microbiomes in Greenland cryoconite holes during the bare ice period

AU - Feord, Helen K.

AU - Zervas, Athanasios

AU - Sipes, Katie

AU - Jaarsma, Ate H.

AU - Tranter, Martyn

AU - Benning, Liane G.

AU - Anesio, Alexandre M.

N1 - Data archiving: no NIOO data

PY - 2026/8

Y1 - 2026/8

N2 - Cryoconite holes host diverse microbiomes on glaciers and ice sheets and are important habitats for supraglacial biogeochemical cycling. Despite reports of relative stability of cryoconite hole community composition on the Greenland Ice Sheet, it is not known how microbial function in cryoconite holes evolves under varying environmental conditions. Here, we address this knowledge gap by quantifying the active community members in five cryoconite holes on the Greenland Ice Sheet over a 3-week period during the 2022 melt season using TotalRNA. Active microbiomes were enriched in cyanobacterial sequences (25%–50%). Spatial variation between cryoconite holes had a greater impact than temporal variation on community composition quantified by rRNA SSUs, suggesting location-distinct and highly stable active microbiomes. In contrast, minor temporal variations in gene expression were identified in the mRNA data (∼1% of quantified transcripts), mostly due to cellular stress responses from washed-in glacier ice algae. Photosynthesis was the dominant active function across all surveyed cryoconite holes and time points, associated with both cyanobacterial taxa and washed-in chlorophyte snow algae. Overall, our data indicate that core cryoconite hole communities stably ensure their ecological roles, such as carbon fixation, regardless of variations in weather, highlighting their resilience and self-sufficiency.

AB - Cryoconite holes host diverse microbiomes on glaciers and ice sheets and are important habitats for supraglacial biogeochemical cycling. Despite reports of relative stability of cryoconite hole community composition on the Greenland Ice Sheet, it is not known how microbial function in cryoconite holes evolves under varying environmental conditions. Here, we address this knowledge gap by quantifying the active community members in five cryoconite holes on the Greenland Ice Sheet over a 3-week period during the 2022 melt season using TotalRNA. Active microbiomes were enriched in cyanobacterial sequences (25%–50%). Spatial variation between cryoconite holes had a greater impact than temporal variation on community composition quantified by rRNA SSUs, suggesting location-distinct and highly stable active microbiomes. In contrast, minor temporal variations in gene expression were identified in the mRNA data (∼1% of quantified transcripts), mostly due to cellular stress responses from washed-in glacier ice algae. Photosynthesis was the dominant active function across all surveyed cryoconite holes and time points, associated with both cyanobacterial taxa and washed-in chlorophyte snow algae. Overall, our data indicate that core cryoconite hole communities stably ensure their ecological roles, such as carbon fixation, regardless of variations in weather, highlighting their resilience and self-sufficiency.

KW - cryoconite holes

KW - Greenland Ice Sheet

KW - melt season

KW - metatranscriptomics

U2 - 10.1093/femsec/fiag074

DO - 10.1093/femsec/fiag074

M3 - Article

C2 - 42417725

AN - SCOPUS:105045489597

SN - 0168-6496

VL - 102

JO - FEMS Microbiology Ecology

JF - FEMS Microbiology Ecology

IS - 8

M1 - fiag074

ER -