Rainfall as a trigger of ecological cascade effects in an Australian groundwater ecosystem

Saccò, M; Blyth, AJ; Humphreys, WF; Cooper, SJB; White, NE; Campbell, M; Mousavi-Derazmahalleh, M; Hua, Q; Mazumder, D; Smith, Colin; Griebler, C; Grice, K

doi:10.26181/605d6f1f73ba0

Rainfall as a trigger of ecological cascade effects in an Australian groundwater ecosystem

journal contribution

posted on 2021-03-26, 05:13 authored by M Saccò, AJ Blyth, WF Humphreys, SJB Cooper, NE White, M Campbell, M Mousavi-Derazmahalleh, Q Hua, D Mazumder, Colin SmithColin Smith, C Griebler, K Grice

© 2021, The Author(s). Groundwaters host vital resources playing a key role in the near future. Subterranean fauna and microbes are crucial in regulating organic cycles in environments characterized by low energy and scarce carbon availability. However, our knowledge about the functioning of groundwater ecosystems is limited, despite being increasingly exposed to anthropic impacts and climate change-related processes. In this work we apply novel biochemical and genetic techniques to investigate the ecological dynamics of an Australian calcrete under two contrasting rainfall periods (LR—low rainfall and HR—high rainfall). Our results indicate that the microbial gut community of copepods and amphipods experienced a shift in taxonomic diversity and predicted organic functional metabolic pathways during HR. The HR regime triggered a cascade effect driven by microbes (OM processors) and exploited by copepods and amphipods (primary and secondary consumers), which was finally transferred to the aquatic beetles (top predators). Our findings highlight that rainfall triggers ecological shifts towards more deterministic dynamics, revealing a complex web of interactions in seemingly simple environmental settings. Here we show how a combined isotopic-molecular approach can untangle the mechanisms shaping a calcrete community. This design will help manage and preserve one of the most vital but underrated ecosystems worldwide.

Funding

We wish to acknowledge the traditional custodians of the land, the Wongai people, and their elders, past, present and emerging. We acknowledge and respect their continuing culture and the contribution they make to the life of Yilgarn region. The authors thank Flora, Peter and Paul Axford of Sturt Meadows Station for their kindness and generosity in providing both accommodation and access to their property. M.S. was supported by a Curtin International Postgraduate Research Scholarship (CIPRS) and an AINSE postgraduate scholarship (PGRA). We acknowledge financial support from the Australia Research Council (Linkage Project LP140100555) and the Australian Government's National Collaborative Research Infrastructure Strategy (NCRIS) for the Centre for Accelerator Science at the Australian Nuclear Science and Technology Organisation. This work was supported by resources provided by the Pawsey Supercomputing Centre with funding from the Australian Government and the Government of Western Australia.

History

Publication Date

2021-02-12

Journal

Scientific Reports

Volume

11

Issue

1

Article Number

3694

Pagination

15p.

Publisher

Springer Nature

ISSN

2045-2322

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