Trace metal biomonitoring in the east Gippsland Lakes estuary using the barnacle amphibalanus variegatus and mussel mytilus edulis
- Authors: Willems, Daniel , Reeves, Jessica , Morrison, Paul , Trestrail, Charlene , Nugegoda, Dayanthi
- Date: 2020
- Type: Text , Journal article
- Relation: Environmental Science and Pollution Research Vol. 27, no. 3 (2020), p. 3361-3383
- Full Text: false
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- Description: The Gippsland Lakes estuary, a Ramsar listed wetland, in Victoria, Australia, is an area of potential concern for metal pollution due to influxes of human population and associated anthropogenic activities. A biomonitoring exercise was undertaken where the concentrations of 9 metals (Cr, Fe, Cu, Zn, As, Se, Ag, Cd and Hg) were analysed in the soft tissue of two common sessile invertebrates: the mussel Mytilus edulis and the barnacle Amphibalanus variegatus from 6 locations on two different occasions throughout the Gippsland Lakes estuary. A salinity gradient exists in the Lakes, from seawater at Lakes Entrance in the east, decreasing down to < 10 PSU in the west at Lake Wellington during times of rainfall, which is a major factor governing the growth and distribution of both species. Dissolved metal levels in general were low; however, Cu at most sites exceeded the 90% trigger values, while all Zn concentrations exceeded the lowest 80% trigger values of the ANZECC marine water quality guidelines for environmental health. Elevated levels of Cu and Zn were found particularly in barnacles at some sites with environmental contamination due to leaching from anti fouling paints and sacrificial zinc anodes. Elevated levels of Ag and Cd were found in mussels at the Hollands Landing site, which is immediately adjacent to a boat ramp, and Cd and Ag at this site are suspected to originate from inland anthropogenic sources. Concentrations of As in M. edulis across all 6 sites in both sampling periods had mean wet weight As concentrations exceeding the maximum level stated in the FSANZ guidelines. A. variegatus contained elevated levels of Hg especially at the North Arm site with a maximum of 13.6 μg Hg/g dry wt., while A. variegatus also showed temporal changes in Hg concentrations across sites. The maximum Hg concentration found in Mytilus edulis was 1.49 μg Hg/g dry wt. at the Hollands Landing site. Previous contaminant studies of biota in the Lakes have targeted sampling of singular predatory or migratory species, such as Black Bream (Acanthopagrus butcheri) and the Burrunan dolphin (Tursiops australis). This is the first biomonitoring study conducted on sessile organisms to assess metal contamination in the system. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
A continental narrative : Human settlement patterns and Australian climate change over the last 35,000 years
- Authors: Williams, Alan , Veth, Peter , Steffen, Will , Ulm, Sean , Turney, Chris , Reeves, Jessica , Phipps, Steven , Smith, Mike
- Date: 2015
- Type: Text , Journal article
- Relation: Quaternary Science Reviews Vol. 123, no. (2015), p. 91-112
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- Description: Drawing on the recent synthesis of Australian palaeoclimate by the OZ-INTIMATE group (Reeves etal., 2013a), we consider the effects of climate systems on past human settlement patterns and inferred demography. We use 5044 radiocarbon dates from ~1750 archaeological sites to develop regional time-series curves for different regions defined in the OZ-INTIMATE compilation as the temperate, tropics, interior and Southern Ocean sectors to explore human-climate relationships in Australia over the last 35,000 years. Correlations undertaken with improved palaeoclimatic data and archaeological records indicate that the regional time-series curves are robust, and can be used as a proxy for human behaviour. However, interrogation of the datasets is essential with artificial peaks and taphonomic over-correction being critical considerations. The time-series curves are interpreted as reflecting population growth, stasis and even decline in phase with terminal Pleistocene/early Holocene climatic fluctuations. This coupling, however, decreases during the last 5000 years, most likely due to increased population levels, greater territoriality, technological solutions to stress, and social and ideational innovation. Curves from all sectors show exponential population growth over the last 5000 years. We identify future research priorities, highlighting the paucity of archaeological records across several parts of Australia (<1 dated site/4,000km2), especially around the fringes of the arid zone, and the need for improved taphonomic correction techniques. Finally, we discuss how these time-series curves represent a first-order framework, not dissimilar to global climate models, which researchers can continue to test and refine with local, regional and continental records. © 2015.