ORCID Profile
0000-0002-8001-0940
Current Organisations
University of Sydney
,
Charles Darwin University
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Publisher: Elsevier BV
Date: 05-2012
DOI: 10.1016/J.JPROT.2012.03.031
Abstract: Polychaetes are often used in toxicological studies to understand mechanisms of resistance and for biomarker detection, however, we know of only a few genetic pathways involved in resistance. We found the marine polychaete Ophelina sp.1 (Opheliidae) in sediment containing high copper levels and investigated this phenomenon by measuring metal accumulation in the worms and changes in gene and protein expression. We sequenced the transcriptome of Ophelina sp.1 from both the impacted and reference sediments using 454-sequencing and analysed their proteomes using differential in gel electrophoresis (DIGE). We used the sequenced transcriptome to guide protein identification. Transcripts coding for the copper chaperone, Atox1, were up-regulated in the worms inhabiting the high copper sediment. In addition, genes coding for respiratory proteins, detoxification proteins and cytoskeletal proteins were significantly altered in metal-exposed worms many of these changes were also detected in the proteome. This dual approach has provided a better understanding of heavy metal resistance in polychaetes and we now have a wider range of suitable indicator genes and proteins for future biomarker development.
Publisher: Springer Science and Business Media LLC
Date: 10-2007
Publisher: Springer Science and Business Media LLC
Date: 27-10-2011
DOI: 10.1007/S00248-011-9966-9
Abstract: Tolerant species of polychaete worms can survive in polluted environments using various resistance mechanisms. One aspect of resistance not often studied in polychaetes is their association with symbiotic bacteria, some of which have resistance to metals and may help the organism to survive. We used "next generation" 454 sequencing of bacterial 16S rRNA sequences associated with polychaetes from a copper- and zinc-polluted harbor and from a reference site to determine bacterial community structure. We found changes in the bacteria at the polluted site, including increases in the abundance of bacteria from the order Alteromonadales. These changes in the bacteria associated with polychaetes may be relatively easy to detect and could be a useful indicator of metal pollution.
Publisher: Springer Science and Business Media LLC
Date: 07-01-1997
Abstract: Studies of the ecology of mangroves show that a wide variety of factors, including salinity, desiccation, disturbance, competition and predation, may affect the distribution and abundance of species. Field studies were done to examine the relative importance of several of these factors in the establishment and early survival of Ceriops tagal, a species common in mid-to high-shore regions of mangrove forests in northern Australia. The fate of marked and tethered propagules was followed to estimate the range of dispersal and the intensity of predation. Propagules were artificially planted under different thicknesses of shade cloth (none, 30%, 80%) and in different habitats (clearing, forest, clearing-forest fringe) to examine the effects of light and soil conditions on survival and growth. Results suggested that dispersal was very limited: only 9% of marked propagules were ever found more than 3 m from the parent tree. Losses to predators were great, with 83% of tethered propagules being damaged or consumed within 3 months. On average, 56% of planted propagules survived for at least 6 weeks and 76% of these initiated growth. Survival in clearings was lower than in other habitats, with 29% fewer surviving six weeks and 48% fewer surviving 15 months. The growth of seedlings was correlated with soil temperature, but the effects of treatments were complex. Overall, results indicated that poor dispersal and establishment were the main factors likely to limit the colonisation and population growth of this species.
Publisher: Elsevier BV
Date: 10-1990
Publisher: Elsevier BV
Date: 12-2013
DOI: 10.1016/J.MARENVRES.2013.10.005
Abstract: We collected polychaete ersity and abundance data at a range of impacted and reference sites near an alumina refinery in Melville Bay, northern Australia. The aims were to measure the impact of sediment modified by the alumina refinery discharge on polychaete communities and secondly to gather baseline data from which to measure future changes. Polychaete communities in both soft-bottom habitats and subtidal areas adjacent to mangrove forests were studied. We also developed and deployed an artificial substratum device to s le polychaetes associated with hard-substrate habitats. For each habitat, polychaete community composition was different between impacted and reference sites and at multiple time points. The impact of future changes either from bioremediation or management practices can be measured against these baseline data. Indicator species analysis was used to identify polychaete species that were significantly different at the locations tested, and we discuss their potential as indicator species.
Publisher: Elsevier BV
Date: 06-2013
DOI: 10.1016/J.JENVRAD.2013.01.007
Abstract: As a key part of water management at the Ranger Uranium Mine (Northern Territory, Australia), stockpile (ore and waste) runoff water was applied to natural woodland on the mine lease in accordance with regulatory requirements. Consequently, the soil in these Land Application Areas (LAAs) presents a range of uranium concentrations. Soil s les were collected from LAAs with different concentrations of uranium and extracts were plated onto LB media containing no (0 ppm), low (3 ppm), medium (250 ppm), high (600 ppm) and very high (1500 ppm) uranium concentrations. These concentrations were similar to the range of measured uranium concentrations in the LAAs soils. Bacteria grew on all plates except for the very high uranium concentrations, where only fungi were recovered. Identifications based on bacterial 16S rRNA sequence analysis showed that the dominant cultivable bacteria belonged to the genus Bacillus. Members of the genera Paenibacillus, Lysinibacillus, Klebsiella, Microbacterium and Chryseobacterium were also isolated from the LAAs soil s les. Fungi were identified by sequence analysis of the intergenic spacer region, and members of the genera Aspergillus, Cryptococcus, Penicillium and Curvularia were dominant on plates with very high uranium concentrations. Members of the Paecilomyces and Alternaria were also present but in lower numbers. These findings indicate that fungi can tolerate very high concentrations of uranium and are more resistant than bacteria. Bacteria and fungi isolated at the Ranger LAAs from soils with high concentrations of uranium may have uranium binding capability and hence the potential for uranium bioremediation.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/BT04162
Abstract: Mangrove forests are an integral part of tropical coastal ecosystems, particularly in northern Australia. In the Northern Territory, studies have determined the extent and species ersity of these associations but little is known of biomass or productivity. We s led the above- and below-ground biomass of the four most abundant species, Avicennia marina, Bruguiera exaristata, Ceriops australis and Rhizophora stylosa, developed allometric relationships and examined partitioning. Unlike many other studies, we s led below-ground biomass, which constituted a substantial proportion (0.29–0.57) of the total dry weight. Our results should be valuable in modelling potential changes in carbon allocation resulting from small- and large-scale ecosystem changes.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/BT04066
Abstract: Mangrove communities in the tropical north of Australia are some of the most species rich in the world, yet surprisingly little is known of their reproductive and vegetative phenology. This study investigated the phenology of four mangrove species: Avicennia marina (Forsk.) Vierh., Ceriops australis (C.T.White) Ballment, T.J.Sm & Stoddart, Rhizophora stylosa Griff. and Sonneratia alba J.Smith, in Darwin Harbour over 24 months. Investigations included documenting the flowering and fruiting phenology, periods of leaf flush and leaf longevity. Flowering in these mangroves generally occurred during the dry season (June–October), with the exception of R. stylosa in which flowering occurred in the middle of the wet (December–February). Fruits and propagules were released in the dry and ‘build up’ periods (August–November), with the exception of A. marina, which released propagules in the middle of the wet season. Fruit and/or propagule maturation took less than 2 months in A. marina and S. alba, whereas in C. australis and R. stylosa maturation took 12 and 11 months, respectively. Timing of new leaf production generally coincided with the wet season, after the flowering and fruiting periods of each of the four species. Periods of leaf flush and leaf fall were often closely linked, and species with longer-lived leaves produced fewer leaves at each period of leaf flush. Maximum leaf longevity varied considerably among mangroves, ranging from 8 months in the lower canopy of S. alba to more than 24 months in C. australis. There was also large variability in leaf longevity among different regions of the canopy, with shade leaves generally living longer than sun leaves, and leaves in the upper canopy (3–7 m) longer than those in the lower regions (0–3 m).
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.JENVRAD.2015.07.014
Abstract: Ranger Uranium Mine (RUM) is situated in the wet-dry tropics of Northern Australia. Land application (irrigation) of stockpile (ore and waste) runoff water to natural woodland on the mine lease is a key part of water management at the mine. Consequently, the soil in these Land Application Areas (LAAs) presents a range of uranium (U) and other metals concentrations. Knowledge of seasonal and temporal changes in soil U and physicochemical parameters at RUM LAAs is important to develop suitable management and rehabilitation strategies. Therefore, soil s les were collected from low, medium, high and very high U sites at RUM LAAs for two consecutive years and the effect of time and season on soil physicochemical parameters particularly U and other major solutes applied in irrigation water was measured. Concentrations of some of the solutes applied in the irrigation water such as sulphur (S), iron (Fe) and calcium (Ca) showed significant seasonal and temporal changes. Soil S, Fe and Ca concentration decreased from year 1 to year 2 and from dry to wet seasons during both years. Soil U followed the same pattern except that we recorded an increase in soil U concentrations at most of the RUM LAAs after year 2 wet season compared to year 2 dry season. Thus, these sites did not show a considerable decrease in soil U concentration from year 1 to year 2. Sites which contained elevated U after wet season 2 also had higher moisture content which suggests that pooling of U containing rainwater at these sites may be responsible for elevated U. Thus, U may be redistributed within RUM LAAs due to surface water movement. The study also suggested that a decrease in U concentrations in LAA soils at very high U (>900 mg kg(-1)) sites is most likely due to transport of particulate matter bound U by surface runoff and U may not be lost from the surface soil due to vertical movement through the soil profile. Uranium attached to particulate matter may reduce its potential for environmental impact. These findings suggest that U is effectively adsorbed by the soils and thus land application may serve as a useful tool for U management in the wet-dry tropics of northern Australia.
Publisher: Elsevier BV
Date: 04-2002
Publisher: Elsevier BV
Date: 11-2011
Publisher: Elsevier BV
Date: 05-2011
Publisher: Elsevier BV
Date: 12-2015
DOI: 10.1016/J.SCITOTENV.2015.07.114
Abstract: The detection of microcontaminants in aquatic environments raises concerns about their potential to exert ecotoxicological effects and impact human health. In contrast to freshwater habitats, little information is available on environmental concentrations in urban estuarine and marine environments. This study investigated an extensive range of organic and inorganic microcontaminants in the Darwin Harbour catchment, a tropical estuary in northern Australia undergoing rapid urbanisation and industrial development. We s led wastewater effluent and surface water from seven sites in Darwin Harbour for pharmaceuticals and personal care products, alkylphenols, hormones, pesticides, herbicides and metals. In vitro bioassays were used to estimate the (anti)estrogenic and (anti)androgenic activities of s les. Seventy-nine of 229 organic microcontaminants analysed were detected at concentrations ranging from 0.01 to 20 μg/L, with acesulfame, paracetamol, cholesterol, caffeine, DEET and iopromide detected at the highest concentrations in wastewater effluent (20 μg/L, 17 μg/L, 11 μg/L, 11 μg/L, 10 μg/L and 7.6 μg/L, respectively). Levels of estrogenic activity ranged from estradiol equivalency quotients (EEQs) of <0.10 to 6.29±0.16 ng/L while levels of androgenic activity ranged from dihydrotestosterone equivalency quotients (DHTEQs) of <3.50 to 138.23±3.71 ng/L. Environmental concentrations of organic microcontaminants were comparable to ranges reported from aquatic environments worldwide with sewage effluent discharges representing the dominant source of entry into Darwin Harbour. The measured concentration range of DEET was higher than ranges reported in previous studies.
Publisher: Wiley
Date: 21-11-2002
Publisher: Elsevier BV
Date: 02-2006
Publisher: Elsevier BV
Date: 09-2014
Publisher: Springer Science and Business Media LLC
Date: 12-2001
Publisher: Springer Science and Business Media LLC
Date: 02-2006
Publisher: Brill
Date: 2013
Publisher: Elsevier BV
Date: 11-2003
Publisher: Springer Science and Business Media LLC
Date: 02-1987
DOI: 10.1007/BF00378716
Publisher: Springer Science and Business Media LLC
Date: 02-1987
DOI: 10.1007/BF00378715
Publisher: Springer Science and Business Media LLC
Date: 04-01-2012
Publisher: Informa UK Limited
Date: 2013
No related grants have been discovered for Keith McGuinness.