02944nas a2200301 4500008004100000022001400041245009600055210007100151260001200222490000700234520204100241653001702282653001902299653002002318653001402338653002302352653002302375100002602398700001702424700002102441700002402462700002602486700001702512700001702529700001802546700002002564856005802584 2022 eng d a1354-101300aResponse of Antarctic soil fauna to climate‐driven changes since the Last Glacial Maximum0 aResponse of Antarctic soil fauna to climate‐driven changes since c01/20220 v283 a

Understanding how terrestrial biotic communities have responded to glacial recession since the Last Glacial Maximum (LGM) can inform present and future responses of biota to climate change. In Antarctica, the Transantarctic Mountains (TAM) have experienced massive environmental changes associated with glacial retreat since the LGM, yet we have few clues as to how its soil invertebrate-dominated animal communities have responded. Here, we surveyed soil invertebrate fauna from above and below proposed LGM elevations along transects located at 12 features across the Shackleton Glacier region. Our transects captured gradients of surface ages possibly up to 4.5 million years and the soils have been free from human disturbance for their entire history. Our data support the hypothesis that soils exposed during the LGM are now less suitable habitats for invertebrates than those that have been exposed by deglaciation following the LGM. Our results show that faunal abundance, community composition, and diversity were all strongly affected by climate-driven changes since the LGM. Soils more recently exposed by glacial recession (as indicated by distances from present ice surfaces) had higher faunal abundances and species richness than older exposed soils. Higher abundances of the dominant nematode Scottnema were found in older exposed soils, while Eudorylaimus, Plectus, tardigrades, and rotifers preferentially occurred in more recently exposed soils. Approximately 30% of the soils from which invertebrates could be extracted had only Scottnema, and these single-taxon communities occurred more frequently in soils exposed for longer periods of time. Our structural equation modeling of abiotic drivers highlighted soil salinity as a key mediator of Scottnema responses to soil exposure age. These changes in soil habitat suitability and biotic communities since the LGM indicate that Antarctic terrestrial biodiversity throughout the TAM will be highly altered by climate warming.

10abiodiversity10aclimate change10aglacial retreat10anematodes10aShackleton Glacier10asoil invertebrates1 aFranco, André, L. C.1 aAdams, Byron1 aDiaz, Melisa, A.1 aLemoine, Nathan, P.1 aDragone, Nicholas, B.1 aFierer, Noah1 aLyons, Berry1 aHogg, Ian, D.1 aWall, Diana, H. uhttps://onlinelibrary.wiley.com/doi/10.1111/gcb.15940