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Deane, D. C.

Publications and source records attributed to Deane, D. C..

2 recordsLinked to original sources

Water plant functional groups: a trait-based classification database for Australian plants

Trait-based functional classifications of species offer improved generality in predicting responses to environmental conditions. Water plant functional groups (WPFG) are one such classification. Grouping plant species based on traits associated with germination, growth and reproductive requirements, WPFG have proven useful in examining plant trait-hydrological relationships in aquatic plant research in Australia. Here, we collate existing information from across academic, government and personal databases to create the most comprehensive compilation of plant taxa assignments to WPFG available. Taxonomic nomenclature was first standardized using accepted names under the Australian Plant Census/Australian Plant Name Index. We then assessed agreement among source classifications and derived a consensus-weighted fuzzy classification that retains uncertainty in WPFG assignment at both the species- and genus-level. The resulting database provides evidence-based classifications for the most commonly observed water plants in temperate Australia, including evidence of affinity to all functional groups. This approach supports greater consistency, transparency and reproducibility in WPFG assignment across studies while allowing users to select the level of classification most appropriate to their application. The database is freely available for download from the Zenodo digital repository.

ecology↗

Quantifying the hydrological niche of swamp vegetation communities using indicator species

Indicator species are typically used to infer the presence of other biota or specific environmental conditions. Here we use indicator species to quantify the hydrological niche of their corresponding vegetation communities within Coastal Upland Swamps of the Sydney Basin Bioregion, Australia. Swamp vegetation organizes naturally into five recognised communities, thought to occupy distinct positions along a hydrological gradient. However, longwall mining reduces hydro-period, potentially impacting the observed vegetation. We modelled the hydrological niche for each community using the relative frequency of 20 vascular plant indicator species (four for each community) and time series soil moisture data from 11 unmined sites across four swamps. We then used this model to predict indicator species frequencies in 3 mine-impacted sites. Indicator species were modelled as a function of the average number of days-per-year that swamps remained saturated at the base of the root zone (30 cm below surface). Hydrological niches were well differentiated for four communities with the estimated optimal mean annual days-per-year saturated ranging from Restioid heath at 16 [<16, 29] (mean {+/-} [95% uncertainty]) to Ti-tree thicket at 352 [322, >353]. Banksia thicket 96 [65, 154] and Cyperoid heath 257 [204, 297] communities were intermediate. However, Sedgeland indicator species showed limited variation with changing saturation, and their hydrological niche remains unclear. The model under-predicted the frequency of Cyperoid heath and over-predicted Banksia thicket indicator species in mine-impacted sites, suggesting vegetation is not yet in equilibrium with hydrology. Results suggest indicator species can provide a reliable basis for determining the hydrological niche of wetland plant communities, which can in turn predict community-level impacts of hydrological change.

ecology↗