Do faunal assemblages reflect the exchange intensity in groundwater zones?

Abstract

The exchange of water with groundwater is a key determinant of water quality and faunal assemblage. Water exchange not only occurs with running waters, but also through percolation, interception (soil, porous alluvium), and evaporation. The aim of this study was to identify how different types of exchange were related to the groundwater faunal assemblage of an alluvial aquifer. Hydrological exchange is largely governed by pore space and thus ultimately by geological formation. In the Marbling Brook catchment of Western Australia the different geological formations did not eventuate in hydrochemically distinct groundwater zones. The cluster analysis of faunal assemblages revealed five groups within the faunal samples which did not reflect spatial patterns such as geological, chemical or topographic features. Discriminant analysis showed that these five groups were best characterized by a range of abiotic features including dissolved oxygen, land-use, and temperature. These variables signal different types and intensities of exchange with the surface.

Differences between groundwater fauna in shallow and in deep intergranular aquifers as an indication of different characteristics of habitats and hydraulic connections

“…However, fauna from deeper boreholes and piezometers can be collected from open boreholes (i.e. boreholes without installed pumps) using the Cvetkov net or modified plankton nets/phreatic nets (Malard et al, 2002;Karanovic, 2006;Schmidt et al, 2007;Eberhard et al, 2009;Hahn and Fuchs, 2009). Air-lift pumps can be utilised in deep boreholes (Malard et al, 1994) but, for effective collection, a high-capacity, compact air-compressor is required.…”

“…Although these numbers appear large, most records are based on a single sampling at single locations and sporadic sampling over long time intervals. This situation has changed over the last three decades, as groundwater ecology research has intensified Schmidt et al, 2007;Gibert and Culver, 2009;Hahn and Fuchs, 2009;Larned, 2012). Ecological studies of groundwater ecosystems, in intergranular aquifers in particular, developed rapidly during the 1990's (Gibert et al, 1990;Danielopol et al, 2001;Gibert, 2001;Gibert and Deharveng, 2002;Hancock et al, 2005;Danielopol and Griebler, 2008).…”

Pilbara stygofauna: deep groundwater of an arid landscape contains globally significant radiation of biodiversity

“…Groundwater of the Swan Coastal Plain and adjacent Darling Range in the south-west supports communities consisting mostly of syncarids and stygophilic copepods (e.g. Schmidt et al 2007;Tang and Knott 2009;GHD 2010;Bennelongia 2009a). Various relatively small cave systems support limited stygofauna communities (e.g.…”

An inter-catchment comparison of groundwater biota in the cotton-growing region of north-western New South Wales

“…Geology and water quality influence biotic distribution as they determine water flow, energy exchange, and habitat structure Hahn 2006;Hancock and Boulton 2009;Griebler and Lueders 2009). Other influences on the distribution of groundwater biota include climate, vegetation, water quality, links with the hyporheic zone, and human activities (Galassi et al 1999a(Galassi et al , 1999bCho and Kim 2000;Jasinska and Knott 2000;Schmidt et al 2007;Tomlinson 2008;Griebler and Lueders 2009;Hahn and Fuchs 2009;Stein et al 2010; Korbel et al 2013). Consequently, aquifers with similar geology, history, and environment might be expected to have similar groundwater faunas.…”

“…karst, alluvial, fracture rock; Galassi et al 2009a;Hahn and Fuchs 2009); however, few studies have examined the relationships between biota and environmental conditions over local (within aquifer) and regional (between similar aquifers) scales (e.g. Schmidt et al 2007;Malard et al 2009;Stoch and Galassi 2010).…”