Browsing by Author "Jolley, DF"
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- ItemThe effect of dissolved nickel and copper on the adult coral Acropora muricata and its microbiome(Elsevier, 2019-04-03) Gissi, F; Reichelt-Brushett, AJ; Chariton, AA; Stauber, JL; Greenfield, P; Humphrey, C; Salmon, M; Stephenson, SA; Cresswell, T; Jolley, DFThe potential impacts of mining activities on tropical coastal ecosystems are poorly understood. In particular, limited information is available on the effects of metals on scleractinian corals which are foundation species that form vital structural habitats supporting other biota. This study investigated the effects of dissolved nickel and copper on the coral Acropora muricata and its associated microbiota. Corals collected from the Great Barrier Reef were exposed to dissolved nickel (45, 90, 470, 900 and 9050 μg Ni/L) or copper (4, 11, 32 and 65 μg Cu/L) in flow through chambers at the National Sea Simulator, Townsville, Qld, Australia. After a 96-h exposure DNA metabarcoding (16S rDNA and 18S rDNA) was undertaken on all samples to detect changes in the structure of the coral microbiome. The controls remained healthy throughout the study period. After 36 h, bleaching was only observed in corals exposed to 32 and 65 μg Cu/L and very high nickel concentrations (9050 μg Ni/L). At 96 h, significant discolouration of corals was only observed in 470 and 900 μg Ni/L treatments, the highest concentrations tested. While high concentrations of nickel caused bleaching, no changes in the composition of their microbiome communities were observed. In contrast, exposure to copper not only resulted in bleaching, but altered the composition of both the eukaryote and bacterial communities of the coral's microbiomes. Our findings showed that these effects were only evident at relatively high concentrations of nickel and copper, reflecting concentrations observed only in extremely polluted environments. Elevated metal concentrations have the capacity to alter the microbiomes which are inherently linked to coral health. Crown Copyright ©2019. Published by Elsevier Ltd.
- ItemMetal speciation and potential bioavailability changes during discharge and neutralisation of acidic drainage water(Elsevier, 2014-05) Simpson, SL; Vardanega, CR; Jarolimek, C; Jolley, DF; Angel, BM; Mosely, LMThe discharge of acid drainage from the farm irrigation areas to the Murray River in South Australia represents a potential risk to water quality. The drainage waters have low pH (2.9–5.7), high acidity (up to 1190 mg L−1 CaCO3), high dissolved organic carbon (10–40 mg L−1), and high dissolved Al, Co, Ni and Zn (up to 55, 1.25, 1.30 and 1.10 mg L−1, respectively) that represent the greatest concern relative to water quality guidelines (WQGs). To provide information on bioavailability, changes in metal speciation were assessed during mixing experiments using filtration (colloidal metals) and Chelex-lability (free metal ions and weak inorganic metal complexes) methods. Following mixing of drainage and river water, much of the dissolved aluminium and iron precipitated. The concentrations of other metals generally decreased conservatively in proportion to the dilution initially, but longer mixing periods caused increased precipitation or adsorption to particulate phases. Dissolved Co, Mn and Zn were typically 95–100% present in Chelex-labile forms, whereas 40–70% of the dissolved nickel was Chelex-labile and the remaining non-labile fraction of dissolved nickel was associated with fine colloids or complexed by organic ligands that increased with time. Despite the different kinetics of precipitation, adsorption and complexation reactions, the dissolved metal concentrations were generally highly correlated for the pooled data sets, indicating that the major factors controlling the concentrations were similar for each metal (pH, dilution, and time following mixing). For dilutions of the drainage waters of less than 1% with Murray River water, none of the metals should exceed the WQGs. However, the high concentrations of metals associated with fine precipitates within the receiving waters may represent a risk to some aquatic organisms. © 2013, Elsevier Ltd.
- ItemThe response of corals and the coral microbiome to metal exposure(Society of Environmental Toxicology and Chemistry, 2017-11-12) Gissi, F; Reichelt-Brushett, AJ; Chariton, AA; Stauber, JL; Stephenson, SA; Cresswell, T; Greenfield, P; Severati, A; Humphrey, C; Jolley, DFThe mining and production of Ni is increasing in tropical regions. The potential impacts of these activities on the valuable coastal ecosystems are poorly understood. Specifically, there is little information available on the effects of Ni to corals. Scleractinian corals are keystone species for coral reefs forming vital structural habitats that support other species, resulting in habitats with high species richness and diversity. For these reasons, it is important that future research provides data which can inform the sustainable development of Ni operations in tropical regions. This study aimed to investigate the effect of dissolved Ni exposure to the scleractinian coral Acropora muricata. Utilising the facilities at the National Sea Simulator (SeaSim), flow through chambers (2.5L) were used to test the effects of Ni and Cu on adult corals and its associated microbiota. Copper was tested alongside Ni to allow for comparisons with past studies. Four replicate chambers were used for; control, 50, 100, 500, 1000, 10000 µg/L Ni and 5, 20, 50, 100 µg/L Cu. Each replicate chamber contained 3 coral fragments (5-8cm in length). After a 96-h exposure, 1 fragment from each chamber was sacrificed for 3 different analytical purposes. One replicate was air blasted to remove tissues which were flash frozen and later used for DNA and RNA sequencing of the microbiota to observe if the bacterial community structure changed in response to metal exposure. A second fragment was air blasted to remove tissues, which were then acid digested and analysed by ICP-MS to determine metal concentrations in the coral tissues. A third replicate was frozen for subsequent metal uptake and distribution analyses using elemental mapping techniques including CT scanning and XRF-ITRAX. Control treatments remained healthy throughout the exposure. After 36 h, bleaching was observed in corals exposed to 50 and 100 µg Cu/L and 10000 µg Ni/L. At 96 h significant discolouration of corals was observed in Ni treatments 500 and 1000 µg Ni/L. The effects of Cu and Ni on adult corals and associated microbiota will be discussed.
- ItemTowards sustainable environmental quality: priority research questions for the Australasian region of Oceania(John Wiley & Sons, Inc, 2019-07-05) Gaw, S; Harford, A; Pettigrove, VJ; Sevicke-Jones, G; Manning, T; Ataria, J; Cresswell, T; Dafforn, KA; Leusch, FDL; Moggridge, B; Cameron, M; Chapman, J; Coates, G; Colville, A; Death, C; Hageman, K; Hassell, KL; Hoak, M; Gadd, JB; Jolley, DF; Karami, A; Kotzakoulakis, K; Lim, R; McRae, N; Metzeling, L; Mooney, T; Myers, J; Pearson, A; Saaristo, M; Sharley, D; Stuthe, J; Sutherland, O; Thomas, O; Tremblay, L; Wood, W; Boxall, ABA; Rudd, MA; Brooks, BWEnvironmental challenges persist across the world, including the Australasian region of Oceania, where biodiversity hotspots and unique ecosystems such as the Great Barrier Reef are common. These systems are routinely affected by multiple stressors from anthropogenic activities, and increasingly influenced by global megatrends (e.g., the food–energy–water nexus, demographic transitions to cities) and climate change. Here we report priority research questions from the Global Horizon Scanning Project, which aimed to identify, prioritize, and advance environmental quality research needs from an Australasian perspective, within a global context. We employed a transparent and inclusive process of soliciting key questions from Australasian members of the Society of Environmental Toxicology and Chemistry. Following submission of 78 questions, 20 priority research questions were identified during an expert workshop in Nelson, New Zealand. These research questions covered a range of issues of global relevance, including research needed to more closely integrate ecotoxicology and ecology for the protection of ecosystems, increase flexibility for prioritizing chemical substances currently in commerce, understand the impacts of complex mixtures and multiple stressors, and define environmental quality and ecosystem integrity of temporary waters. Some questions have specific relevance to Australasia, particularly the uncertainties associated with using toxicity data from exotic species to protect unique indigenous species. Several related priority questions deal with the theme of how widely international ecotoxicological data and databases can be applied to regional ecosystems. Other timely questions, which focus on improving predictive chemistry and toxicology tools and techniques, will be important to answer several of the priority questions identified here. Another important question raised was how to protect local cultural and social values and maintain indigenous engagement during problem formulation and identification of ecosystem protection goals. Addressing these questions will be challenging, but doing so promises to advance environmental sustainability in Oceania and globally. © 2019 The Authors