Social and Behavioral Sciences Commons^™

Bryophyte Species Composition Over Moisture Gradients In The Windmill Islands, East Antarctica: Development Of A Baseline For Monitoring Climate Change Impacts, J Wasley, S A. Robinson, J D. Turnbull, D H. King, W Wanek, M Popp

Faculty of Science - Papers (Archive)

Extreme environmental conditions prevail on the Antarctic continent and limit plant diversity to cryptogamic communities, dominated by bryophytes and lichens. Even small abiotic shifts, associated with climate change, are likely to have pronounced impacts on these communities that currently exist at their physiological limit of survival. Changes to moisture availability, due to precipitation shifts or alterations to permanent snow reserves, will most likely cause greatest impact. In order to establish a baseline for determining the effect of climate change on continental Antarctic terrestrial communities and to better understand bryophyte species distributions in relation to moisture in a floristically important Antarctic …

A Simple Post-Hoc Method To Add Spatial Context To Predictive Species Distribution Models, Michael B. Ashcroft, Kristine O. French, Laurie A. Chisholm

Faculty of Science - Papers (Archive)

Methods to incorporate spatial context into species distribution models (SDMs) are underutilised, with predictions usually based only on environmental space and ignoring geographic space. The goals of this study were to demonstrate a relatively simple post-hoc method to include spatial context in SDMs and to quantify the improvement over purely niche-based models. The method involved producing a standard niche-based model using established techniques, such as Maxent, and then calculating the neighbourhood average of the model output in geographic space. In effect, we tested whether the spatially averaged model output was better at predicting species distributions than the raw model output. …

Are Competitive Effects Of Native Species On An Invader Mediated By Water Availability?, Tanya J. Mason, Kristine French, Ken Russell

Faculty of Science - Papers (Archive)

Question: Climate change processes could influence the dynamics of biotic interactions such as plant competition, especially in response to disturbance phenomena such as invasional processes. Are competitive effects of native species on an invadermediated bywater availability?

Location: Glasshouse facility, New SouthWales, Australia.

Methods: We constructed competitive hierarchies for a representative suite of species from coastal dune communities that have been invaded by the Asteraceae shrub, bitou (Chrysanthemoides monilifera subsp. rotundata). We used a comparative phytometer approach, where the invader species was grown with or without a suite of native species in glasshouse trials. This was used to construct competition hierarchies …

Larval Tolerance To Salinity In Three Species Of Australian Anuran: An Indication Of Saline Specialisation In Litoria Aurea, Brian D. Kearney, Phillip G. Byrne, Richard D. Reina

Faculty of Science - Papers (Archive)

Recent anthropogenic influences on freshwater habitats are forcing anuran populations to rapidly adapt to high magnitude changes in environmental conditions or face local extinction. We examined the effects of ecologically relevant elevated salinity levels on larval growth, metamorphosis and survival of three species of Australian anuran; the spotted marsh frog (Limnodynastes tasmaniensis), the painted burrowing frog (Neobatrachus sudelli) and the green and golden bell frog (Litoria aurea), in order to better understand the responses of these animals to environmental change. Elevated salinity (16% seawater) negatively impacted on the survival of L. tasmaniensis (35% survival) …

Competition Strength Of Two Significant Invasive Species In Coastal Dunes, K French

Faculty of Science - Papers (Archive)

To investigate the effect of increased nutrient availability on competition amongst invasive and native plants, I measured changes in above and below ground biomass of Chrysanthemoides monilifera spp. rotundata (bitou bush) and Asparagus aethiopicus (asparagus fern) competing with two native species, Banksia integrifolia and Ficinia nodosa, under highand low-nutrient regimes. Bitou bush, as a primary invader, was competitive under all conditions lowering the growth of native species in both high and low nutrients. Asparagus fern as a secondary invader, did not influence growth of native species but responded, like bitou bush, to high nutrients. Native species were generally negatively …

The Use Of Representative Species As Surrogates For Wetland Inundation, Kerrylee Rogers, Timothy J. Ralph, Neil Saintilan

Faculty of Science - Papers (Archive)

The complex task of determining the inundation requirements of large floodplain wetlands is often simplified through the use of representative, umbrella or flagship species. This subset of species is targeted based on the assumption that their collective inundation requirements serve as a surrogate for the broader suite of species found within the wetland. We tested the application of representative species commonly used in wetland and water management planning in the Murray-Darling Basin. In a review of the water requirements of 155 plants and animals, we collated information on preferred inundation timing, duration, depth, rate of rise and fall, and inter-flood …

Recruitment Limitation Of Native Species In Invaded Coastal Dune Communities, Kristine O. French, Natalie A. Sullivan, Tanya J. Mason

Faculty of Science - Papers (Archive)

"Recruitment limitation may limit the ability of sites to regenerate after disturbances such as weed invasion and weed management. We investigated seed bank constraints and dispersal limitation in coastal dune communities on the east coast of Australia. The ability of sites to regenerate naturally following weed removal was assessed in coastal dune communities invaded by the invasive alien, bitou bush (Chrysanthemoides monilifera subsp. rotundata). To investigate recruitment limitation, seed banks and vegetation of invaded, native, intensively managed (selective application of herbicide and some re-vegetation) and extensively managed (large-scale, non-selective herbicide application) sites were compared. We investigated the dispersal mechanisms of …

An Assessment Of Three Harpacticoid Copepod Species For Use In Ecotoxicological Testing, Daniel J. Ward, Victor Perez-Landa, David A. Spadaro, Stuart L. Simpson, Dianne F. Jolley

Faculty of Science - Papers (Archive)

The relatively short life cycles of harpacticoid copepods makes them appropriate animals for use in tests that rapidly assess the #180, sublethal, or chronic effects of sediment contaminants. In this study, four harpacticoid copepod species (Nitocra spinipes, Tisbe tenuimana, Robertgurneya hopkinsi, and Halectinosoma sp.) were isolated from clean marine sediments, and procedures for laboratory culturing were developed. Halectinosoma sp. was abandoned due to handling difficulties. For the remaining species, the influence of food type and quantity on life-cycle progression was assessed. A mixed diet, comprising two species of algae (Tetraselmis sp. and Isochrysis sp.) and fish food (Sera …

Novel Technique Shows Different Hydrophobic Chemical Signatures Of Exotic And Indigenous Plant Soils With Similar Effects Of Extracts On Indigenous Species Seedling Growth, Emilie-Jane Ens, Kristine O. French, John B. Bremner, Jurgen Korth

Faculty of Science - Papers (Archive)

Changes to ecosystem abiotic parameters are regarded as possible mechanisms facilitating plant invasion and community composition shifts. This study compared the hydrophobic chemical signatures of soil from exotic bitou bush (Chrysanthemoides monilifera spp. rotundata) invaded, indigenous acacia (Acacia longifolia var. sophorae) dominated and bare sand (unvegetated) habitats using a novel, rapid, capturing technique which utilised AmberliteA (R) XAD4 resin filled bags that were placed in situ. The hydrophobic chemical signature of the bitou bush soil extract was significantly different to the acacia soil and bare sand extracts. High concentrations of 18 sesquiterpenes dominated the hydrophobic signature of the bitou bush …

Variable Direct And Indirect Effects Of A Habitat-Modifying Invasive Species On Mortality Of Native Fauna, James E. Byers, Jeffrey T. Wright, Paul E. Gribben

Faculty of Science - Papers (Archive)

Habitat-modifying invasive species can influence rates of predation on native prey either directly by providing protective structure or indirectly by modifying traits of prey species responding to the habitat. The alga Caulerpa taxifolia is one of the most successful invasive species of shallow-water marine systems globally, often provisioning habitat in areas previously lacking in vegetated structure. We experimentally evaluated the direct effect of Caulerpa to provide refuge for the native clam Anadara trapezia and how this balances with its influence on two trait-mediated indirect interactions that may increase Anadara's susceptibility to predators. Specifically, Caulerpa's alteration of physical and chemical properties …

Effects Of Soil Temperature Regimes After Fire On Seed Dormancy And Germination In Six Australian Fabaceae Species, Victor Santana, Ross A. Bradstock, Mark Ooi, Andrew J. Denham, Tony D. Auld, M Baeza

Faculty of Science - Papers (Archive)

In addition to direct fire cues such as heat, smoke and charred wood, the passage of fire leads indirectly to changes in environmental conditions which may be able to break physical dormancy in hard-coated seeds. After a fire, the open canopy and the burnt material lying on the surface alter the thermal properties of the soil, resulting in elevated soil temperatures for long periods of time. We simulated daily temperature regimes experienced at different depths of soil profile after a summer fire. Our aim was to determine whether these temperature regimes and the duration of exposure (5, 15 and 30 …

Establishment And Persistence Of Species-Rich Patches In A Species-Poor Landscape: Role Of A Structure-Forming Subtidal Barnacle, A. R. Davis, David. W. Ward

Faculty of Science - Papers (Archive)

Some sessile invertebrates are capable of maintaining space in barren habitats produced by sea urchins, thereby creating species-rich patches in a species-poor landscape. We sought to determine the role of a large and common barnacle, Austrobalanus imperator, in the establishment and persistence of these species-rich patches. Barnacle density was modified in 2 experiments at sites in southeastern Australia. The first experiment concerned community establishment and involved the addition of barnacles in 4 densities (zero [control], low, medium and high) to plots on vertical rock surfaces. The addition of barnacles at ecologically realistic densities and spatial arrangements rapidly resulted in statistically …

Thermal Attributes Of Chrysomya Species, James F. Wallman, Leigh Nelson, Mark P. Dowton

Faculty of Science - Papers (Archive)

The correct identification of forensically important arthropods for post-mortem interval estimation is crucial, as the rate of larval development can vary substantially between species. The identification of forensically important blowflies of the genus Chrysomya (Diptera: Calliphoridae) may be hampered by their close morphological similarities, especially as immatures. The aim of this study was to establish whether genetically closely related blowfly species would share similar developmental profiles. This could permit the application of developmental data to a number of closely related species, including those for which thermodevelopmental studies are lacking. If Australian Chrysomya were found to share developmental profiles, identification of …

Plasma Cholinesterase Characteristics In Native Australian Birds: Significance For Monitoring Avian Species For Pesticide Exposure, Karen J. Fildes, Judit K. Szabo, Lee Astheimer, Michael Hooper, William A. Buttemer

Faculty of Science - Papers (Archive)

Cholinesterase-inhibiting pesticides are applied throughout Australia to control agricultural pests. Blood plasma cholinesterase (ChE) activity is a sensitive indicator of exposure to organophosphorus insecticides in vertebrates. To aid biomonitoring and provide reference data for wildlife pesticide-risk assessment, plasma acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were characterised in nine species of native bird: King Quails (Excalfactoria chinensis), Budgerigars (Melopsittacus undulatus), White-plumed Honeyeaters (Lichenostomas penicillatus), Yellow-throated Miners (Manorina flavigula), Willie Wagtails (Rhipidura leucophrys), Australian Reed-Warblers (Acrocephalus australis), Brown Songlarks (Cincloramphus cruralis), Double-barred Finches (Taeniopygia bichenovii) and Australasian Pipits (Anthus novaeseelandiae). Plasma ChE activities in all species were within the range of most …

Molecular And Morphological Description Of A Hepatozoon Species In Reptiles And Their Ticks In The Northern Territory, Australia, Inger-Marie E. Vilcins, Beata Ujvari, Julie M. Old, Elizabeth Deane

Faculty of Science - Papers (Archive)

Ticks, representing 3 species of Amblyomma, were collected from the water python (Liasis fuscus) and 3 additional reptile species in the Northern Territory, Australia, and tested for the presence of Hepatozoon sp., the most common blood parasites of snakes. In addition, blood smears were collected from 5 reptiles, including the water python, and examined for the presence of the parasite. Hepatozoon sp. DNA was detected in all tick and reptile species, with 57.7% of tick samples (n = 187) and 35.6% of blood smears (n = 35) showing evidence of infection. Phylogenetic analysis of the 18S rRNA gene demonstrated that …

Macroglobulin And Haptoglobin Suppress Amyloid Formation By Interacting With Prefibrillar Protein Species, Justin J. Yerbury, Janet R. Kumita, Sarah Meehan, Christopher M. Dobson, Mark R. Wilson

Faculty of Science - Papers (Archive)

α₂-Macroglobulin (α₂M) and haptoglobin (Hp) are both abundant secreted glycoproteins that are best known for their protease trapping and hemoglobin binding activities, respectively. Like the small heat shock proteins, both these glycoproteins have in common the ability to protect a range of proteins from stress-induced amorphous aggregation and have been described as extracellular chaperones. Using an array of biophysical techniques, this study establishes that in vitro at substoichiometric levels and under physiological conditions α₂M and Hp both inhibit the formation of amyloid fibrils from a range of proteins. We also provide evidence that both …

Uptake And Internalisation Of Copper By Three Marine Microalgae: Comparison Of Copper-Sensitive And Copper-Tolerant Species, Jacqueline L. Levy, Brad M. Angel, Jennifer L. Stauber, Wing L. Poon, Stuart L. Simpson, Shuk Han Cheng, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Although it has been well established that different species of marine algae have different sensitivities to metals, our understanding of the physiological and biochemical basis for these differences is limited. This study investigated copper adsorption and internalisation in three algal species with differing sensitivities to copper. The diatom Phaeodactylum tricornutum was particularly sensitive to copper, with a 72-h IC50 (concentration of copper to inhibit growth rate by 50%) of 8.0 μg Cu L^-1, compared to the green algae Tetraselmis sp. (72-h IC50 47 μg Cu L^-1) and Dunaliella tertiolecta (72-h IC50 530 μg Cu L^{-1 …}

Soil Temperatures During Autumn Prescribed Burning: Implications For The Germination Of Fire Responsive Species?, Trent D. Penman, A L. Towerton

Faculty of Science - Papers (Archive)

Prescribed fire is a widely applied management tool in native forests. There have been concerns raised about the ecological impacts of prescribed fire on native flora. One aspect of the debate is the extent towhich prescribed fire heats the soil to levels reported to trigger germination in the soil seed banks.We used Thermochrons to test soil temperatures at 2 and 5 cm in prescribed burns in dry sclerophyll forests. Soil temperatures during the burns were generally low (<40◦C) with less than 5% of sites being exposed to temperatures necessary for the germination of fire-dependent shrub species. High temperatures were associated with high fuel consumption and large woody debris. This information suggests that prescribed fires, carried out according to standard practices, in these forests are unlikely to trigger germination in the majority of the soil-stored seed banks. If ecological burns in these forests are aimed at promoting populations of senescing obligate seeder species, they need to be hotter than standard practice if they are to achieve their objectives, although we acknowledge that there are inherent risks associated with hotter burns.

Current Applications Of Hyperspectral Remote Sensing In The Discrimination Of Australian Eucalypt Species, Laurie A. Chisholm, B Datt

Faculty of Science - Papers (Archive)

hyperspectral remote sensing provides detail on biophysical variables related to forest ecosystem processes useful for tracking and predicting structure and function of vegetation considerable potential of laboratory spectrometry and near-range work in the field to derive stress indicators and changes in cholorphyll content has been demonstrated that includes a range of studies conducted on unique Australian vegetation types.

Effects Of Javan Rusa Deer (Cervus Timorensis) On Native Plant Species In The Jibbon-Bundeena Area, Royal National Park, New South Wales, David Keith, Belinda Pellow

Faculty of Science - Papers (Archive)

A reconnaissance survey and exclosure experiment were carried out to examine the effects of Javan rusa deer on native flora and vegetation in Royal National Park on the southern outskirts of Sydney, Australia. Of 78 native plant species examined during the survey, only nine showed no evidence of vertebrate herbivory or physical damage and the majority of these plants were ferns and sedges. The other 69 species showed effects that included defoliation (young and/or old leaves), removal of shoots, bark-stripping, stem breakages and destruction or consumption of reproductive material. These effects varied in severity between species and from place to …

A New Species Of Goodenia (Goodeniaceae) From Nocoleche Nature Reserve, Far Western Plains, New South Wales, Belinda J. Pellow, John L. Potter

Faculty of Science - Papers (Archive)

Goodenia nocoleche was cultivated in sediment collected from a freshwater temporary wetland in Nocoleche Nature Reserve. Here it is newly described and illustrated with additional notes on its ecology.