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bioRxiv · 10.1101/2023.10.29.564639

Diving into spring biodiversity: A natural heritage assessment of Australia's Great Artesian Basin discharge wetlands

Abstract

ContextThe Great Artesian Basin (GAB) feeds thousands of springs in Australias arid centre, supporting relictual species not found elsewhere on Earth. Springs are considerably threatened by ongoing water abstraction by industry. Robust management plans are needed to prevent further extirpations of GAB taxa, but fundamental biodiversity knowledge is lacking. AimsWe aimed to characterise major organismal groups in South Australian GAB springs and surrounding wetlands, their conservation and taxonomic status, and potential biodiversity hotspots and connectivity of spring ecosystems. MethodsFocusing on South Australia as a case study, we conducted a comprehensive review of GAB spring biota based on the published scientific and grey literature. Key resultsAlmost 500 taxa have been recorded from GAB springs, the majority being invertebrates. Community composition is highly heterogeneous among spring clusters and the true extent of spring biodiversity is far greater than currently known. ConclusionsGAB springs have intrinsic value as refugia for both endemics and cosmopolitan taxa. GAB invertebrates are poorly conserved and largely lacking in taxonomic knowledge. We highlight several potential biodiversity hotspots that have been overlooked in the literature. ImplicationsFundamental biodiversity information on the GAB is crucial for decision-making in conservation management, for industry, and for Traditional Custodians. Lay summaryThe Great Artesian Basin (GAB) is Australias largest freshwater resource. Springs fed by the GAB support many species not found elsewhere on Earth, but conservation is hindered by a lack of fundamental knowledge about the plants, animals, and fungi reliant on these habitats. Using South Australia as a case study, we provide a comprehensive review of GAB biodiversity in that state.

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BibTeXRIS

Beasley-Hall, P. G., Hedges, B. A., Cooper, S. J. B., Austin, A. D., Guzik, M. T.. 2023-11-01. Diving into spring biodiversity: A natural heritage assessment of Australia's Great Artesian Basin discharge wetlands. https://doi.org/10.1101/2023.10.29.564639

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