title: Age-related environmental gradients influence invertebrate distribution in the Prince Charles Mountains, East Antarctica.
abstract: The potential impact of environmental change on terrestrial Antarctic ecosystems can be explored by inspecting biodiversity patterns across large-scale gradients. Unfortunately, morphology-based surveys of Antarctic invertebrates are time-consuming and limited by the cryptic nature of many taxa. We used biodiversity information derived from high-throughput sequencing (HTS) to elucidate the relationship between soil properties and invertebrate biodiversity in the Prince Charles Mountains, East Antarctica. Across 136 analysed soil samples collected from Mount Menzies, Mawson Escarpment and Lake Terrasovoje, we found invertebrate distribution in the Prince Charles Mountains significantly influenced by soil salinity and/or sulfur content. Phyla Tardigrada and Arachnida occurred predominantly in low-salinity substrates with abundant nutrients, whereas Bdelloidea (Rotifera) and Chromadorea (Nematoda) were more common in highly saline substrates. A significant correlation between invertebrate occurrence, soil salinity and time since deglaciation indicates that terrain age indirectly influences Antarctic terrestrial biodiversity, with more recently deglaciated areas supporting greater diversity. Our study demonstrates the value of HTS metabarcoding to investigate environmental constraints on inconspicuous soil biodiversity across large spatial scales.
authors.affiliation: Australian Centre for Ancient DNA, University of Adelaide, Adelaide, South Australia 5005, Australia; Antarctic Biological Research Initiative, Bolivar, South Australia 5110, Australia.
authors.forename: Paul
authors.identifier: 0000-0001-7894-4042
authors.initials: P
authors.lastname: Czechowski
authors.affiliation: Institute for Applied Ecology , University of Canberra , Canberra, Australian Capital Territory 2601 , Australia.
authors.forename: Duanne
authors.initials: D
authors.lastname: White
authors.affiliation: Australian Centre for Ancient DNA, University of Adelaide, Adelaide, South Australia 5005, Australia; Australian Antarctic Division, Kingston, Tasmania 7050, Australia; Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, Tasmania 7001, Australia.
authors.forename: Laurence
authors.initials: L
authors.lastname: Clarke
authors.affiliation: Plant and Soil Health , South Australian Research and Development Institute , Waite Campus, Urrbrae, South Australia 5064 , Australia.
authors.forename: Alan
authors.initials: A
authors.lastname: McKay
authors.affiliation: Australian Centre for Ancient DNA , University of Adelaide , Adelaide, South Australia 5005 , Australia.
authors.forename: Alan
authors.initials: A
authors.lastname: Cooper
authors.affiliation: South Australian Museum, Science Centre, Adelaide, South Australia 5000, Australia; School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5001, Australia.
authors.forename: Mark I
authors.initials: MI
authors.lastname: Stevens
keywords: Antarctica; environmental DNA; gradient; high-throughput sequencing; invertebrates; salinity