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McCarthy JS, Brown KE, King CK, Nielsen UN, Plaisted K, Wallace SMN, Reichman SM. Population growth of two limno-terrestrial Antarctic microinvertebrates in different aqueous soil media. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:33086-33097. [PMID: 38676867 PMCID: PMC11133119 DOI: 10.1007/s11356-024-32905-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 03/10/2024] [Indexed: 04/29/2024]
Abstract
Terrestrial microinvertebrates provide important carbon and nutrient cycling roles in soil environments, particularly in Antarctica where larger macroinvertebrates are absent. The environmental preferences and ecology of rotifers and tardigrades in terrestrial environments, including in Antarctica, are not as well understood as their temperate aquatic counterparts. Developing laboratory cultures is critical to provide adequate numbers of individuals for controlled laboratory experimentation. In this study, we explore aspects of optimising laboratory culturing for two terrestrially sourced Antarctic microinvertebrates, a rotifer (Habrotrocha sp.) and a tardigrade (Acutuncus antarcticus). We tested a soil elutriate and a balanced salt solution (BSS) to determine their suitability as culturing media. Substantial population growth of rotifers and tardigrades was observed in both media, with mean rotifer population size increasing from 5 to 448 ± 95 (soil elutriate) and 274 ± 78 (BSS) individuals over 60 days and mean tardigrade population size increasing from 5 to 187 ± 65 (soil elutriate) and 138 ± 37 (BSS) over 160 days. We also tested for optimal dilution of soil elutriate in rotifer cultures, with 20-80% dilutions producing the largest population growth with the least variation in the 40% dilution after 36 days. Culturing methods developed in this study are recommended for use with Antarctica microinvertebrates and may be suitable for similar limno-terrestrial microinvertebrates from other regions.
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Affiliation(s)
- Jordan S McCarthy
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville, VIC, 3010, Australia
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Kathryn E Brown
- Environmental Stewardship Program, Australian Antarctic Division, 203 Channel Highway, Kingston, TAS, 7050, Australia
| | - Catherine K King
- Environmental Stewardship Program, Australian Antarctic Division, 203 Channel Highway, Kingston, TAS, 7050, Australia
| | - Uffe N Nielsen
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2750, Australia
| | - Katie Plaisted
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville, VIC, 3010, Australia
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Stephanie M N Wallace
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville, VIC, 3010, Australia
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Suzie M Reichman
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville, VIC, 3010, Australia.
- School of BioSciences, University of Melbourne, Parkville, VIC, 3010, Australia.
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Brown KE, Wasley J, King CK. Assessing risks from fuel contamination in Antarctica: Dynamics of diesel ageing in soil and toxicity to an endemic nematode. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 249:114345. [PMID: 36508834 DOI: 10.1016/j.ecoenv.2022.114345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Fuel spills are a major source of contamination in terrestrial environments in Antarctica. Little is known of the effects of hydrocarbon contaminants in fuels on Antarctic terrestrial biota, and how these change as fuel ages within soil. In this study we investigate the sensitivity of juveniles of the endemic Antarctic nematode Plectus murrayi to diesel-spiked soil. Toxicity tests were conducted on soil elutriates, and changes in concentrations of hydrocarbons, polar compounds and PAHs were assessed as the spiked soil was artificially aged at 3 °C over a 45-week period, representing multiple summer seasons of fuel degradation. Nematodes were most sensitive to elutriates made from freshly spiked soils (LC50 419 μg/L TPH and 156 μg/L TPH-SG), with a subsequent decline in toxicity observed in the first 6 weeks of laboratory ageing (LC50 2945 μg/L TPH and 694 μg/L TPH-SG). Effects were still evident up to 45 weeks (lowest observed effect concentration 2123 μg/L TPH) despite hydrocarbons being depleted from soils with ageing (84 % loss) and elutriates becoming dominated by polar metabolites (95 % polar). Nematode sensitivity throughout the ageing period showed evidence of a relationship between LC50 and the proportions of the lighter carbon range fraction of TPH in elutriates, the F2 fraction (C10-14). This study is the first to estimate the sensitivity of Antarctic terrestrial fauna to diesel and provides novel data on the dynamics of fuel chemistry under Antarctic conditions and how this influences toxicity. Findings contribute to predicting ecological risk at existing diesel fuel spill sites in Antarctica, to the derivation of site-specific remediation targets, and to environmental guidelines to assess ecosystem health.
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Affiliation(s)
- Kathryn E Brown
- Australian Antarctic Division, Kingston, Tasmania, Australia.
| | - Jane Wasley
- Australian Antarctic Division, Kingston, Tasmania, Australia.
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McCarthy JS, Wallace SMN, Brown KE, King CK, Nielsen UN, Allinson G, Reichman SM. Preliminary investigation of effects of copper on a terrestrial population of the antarctic rotifer Philodina sp. CHEMOSPHERE 2022; 300:134413. [PMID: 35385763 DOI: 10.1016/j.chemosphere.2022.134413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Terrestrial microinvertebrates in Antarctica are potentially exposed to contaminants due to the concentration of human activity on ice-free areas of the continent. As such, knowledge of the response of Antarctic microinvertebrates to contaminants is important to determine the extent of anthropogenic impacts. Antarctic Philodina sp. were extracted from soils and mosses at Casey station, East Antarctica and exposed to aqueous Cu for 96 h. The Philodina sp. was sensitive to excess Cu, with concentrations of 36 μg L-1 Cu (48 h) and 24 μg L-1 Cu (96 h) inhibiting activity by 50%. This is the first study to be published describing the ecotoxicologically derived sensitivity of a rotifer from a terrestrial population to metals, and an Antarctic rotifer to contaminants. It is also the first study to utilise bdelloid rotifer cryptobiosis (chemobiosis) as a sublethal ecotoxicological endpoint. This preliminary investigation highlights the need for further research into the responses of terrestrial Antarctic microinvertebrates to contaminants.
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Affiliation(s)
- Jordan S McCarthy
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville VIC, 3010, Australia; School of BioSciences, University of Melbourne, Parkville VIC, 3010, Australia.
| | - Stephanie M N Wallace
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville VIC, 3010, Australia; School of BioSciences, University of Melbourne, Parkville VIC, 3010, Australia.
| | - Kathryn E Brown
- Environmental Protection Program, Australian Antarctic Division, Kingston TAS, 7050, Australia.
| | - Catherine K King
- Environmental Protection Program, Australian Antarctic Division, Kingston TAS, 7050, Australia.
| | - Uffe N Nielsen
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith NSW, 2751, Australia.
| | - Graeme Allinson
- School of Science, RMIT University, Melbourne VIC, 3000, Australia.
| | - Suzie M Reichman
- Centre for Anthropogenic Pollution Impact and Management (CAPIM), University of Melbourne, Parkville VIC, 3010, Australia; School of BioSciences, University of Melbourne, Parkville VIC, 3010, Australia.
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Koppel DJ, Bishop J, Kopalová K, Price GAV, Brown KE, Adams MS, King CK, Jolley DF. Metal lability and environmental risk in anthropogenically disturbed Antarctic melt streams. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 287:117627. [PMID: 34426394 DOI: 10.1016/j.envpol.2021.117627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 06/07/2021] [Accepted: 06/18/2021] [Indexed: 06/13/2023]
Abstract
Antarctic melt streams are important ecosystems that increasingly face contaminant pressures from anthropogenic sources. Metal contaminants are often reported in the limno-terrestrial environment but their speciation is not well characterised, making environmental risk assessments difficult. This paper characterises labile metal concentrations in five melt streams and three shallow lakes around the Casey and Wilkes research stations in East Antarctica using chemical extracts and field deployments of diffusive gradients in thin-film (DGT) samplers. An acute toxicity test with field-collected Ceratadon purpeus and taxonomic identification of diatoms in melt streams were used to infer environmental risk. Copper and zinc were the most labile metals in the melt streams. DGT-labile copper concentrations were up to 3 μg Cu L-1 in melt-stream waters but not labile below the sediment-water interface. DGT-labile zinc concentrations were consistent above and below the sediment-water interface at concentrations up to 14 μg Zn L-1 in four streams, but one stream showed evidence of zinc mineralisation in the sediment with a flux to overlying and pore waters attributed to the reductive dissolution of iron and manganese oxides. Other metals, such as chromium, nickel, and lead were acid-extractable from the sediments, but not labile in pore waters or overlying waters. All streams had unique compositions of freshwater diatoms, but one had particularly reduced diversity and richness, which correlated to metal contamination and sediment physico-chemical properties such as a finer particle size. In laboratory bioassays with field-collected samples of the Antarctic moss C. purpeus, there was no change in photosynthetic efficiency following 28-d exposure to 700, 900, 1060, or 530 μg L-1 of cadmium, copper, nickel, and zinc, respectively. This study shows that microorganisms such as diatoms may be at greater risk from contaminants than mosses, and highlights the importance of geochemical factors controlling metal lability.
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Affiliation(s)
- Darren J Koppel
- Faculty of Science, University of Technology Sydney, NSW, Australia; Faculty of Science and Engineering, Curtin University, Perth, WA, Australia; CSIRO Land and Water, Lucas Heights, NSW, Australia.
| | - Jordan Bishop
- Department of Ecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Kateřina Kopalová
- Department of Ecology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Gwilym A V Price
- Faculty of Science, University of Technology Sydney, NSW, Australia; CSIRO Land and Water, Lucas Heights, NSW, Australia
| | - Kathryn E Brown
- Australian Antarctic Division, Kingston, Tasmania, Australia
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Koppel DJ, Whitelaw N, Adams MS, King CK, Jolley DF. The microalga Phaeocystis antarctica is tolerant to salinity and metal mixture toxicity interactions. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:1362-1375. [PMID: 34351327 DOI: 10.1039/d1em00233c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Salinity in the Antarctic nearshore marine environment is seasonally dynamic and climate change is driving greater variability through altered sea ice seasons, ocean evaporation rates, and increased terrestrial ice melt. The greatest salinity changes are likely to occur in the nearshore environment where elevated metal exposures from historical waste or wastewater discharge occur. How salinity changes affect metal toxicity has not yet been investigated. This study investigated the toxicity of cadmium, copper, nickel, lead, and zinc, and their equitoxic mixtures across a salinity gradient to the Antarctic marine microalga Phaeocystis antarctica. In the metal-free control exposures, algal population growth rates were significantly lower at salinities <20 PSU or >35 PSU compared to the control growth rate at 35 PSU of 0.60 ± 0.05 doublings per day and there was no growth below 10 or above 68 PSU. Salinity-induced changes to metal speciation and activity were investigated using the WHAM VII model. Percentages of free ion activity and metal-organic complexes increased at decreasing salinities while the activity of inorganic metal complexes increased with increasing salinities. Despite metal speciation and activity changes, toxicity was generally unchanged across the salinity gradient except that there was less copper toxicity and more lead toxicity than model predictions at salinities of 15 and 25 PSU and antagonistic interactions in metal-mixture treatments. In mixtures with and without copper, it was shown that copper was responsible for ∼50% of the antagonism from observed toxicity at salinities below 45 PSU. Across all treatments, using different metal fractions in toxicity models did not improve toxicity predictions compared to dissolved metal concentrations. These results provide evidence that P. antarctica is unlikely to be at a greater risk from metal contaminants as a result of salinity changes.
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Affiliation(s)
- Darren J Koppel
- Faculty of Science and Engineering, Curtin University, Perth, WA, Australia.
- Faculty of Science, Medicine, and Health, University of Wollongong, Wollongong, NSW, Australia
- CSIRO Land and Water, Lucas Heights, NSW, Australia
| | - Nicholas Whitelaw
- Faculty of Science, Medicine, and Health, University of Wollongong, Wollongong, NSW, Australia
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Koppel DJ, Av Price G, Brown KE, Adams MS, King CK, Gore DB, Jolley DF. Assessing metal contaminants in Antarctic soils using diffusive gradients in thin-films. CHEMOSPHERE 2021; 269:128675. [PMID: 33657749 DOI: 10.1016/j.chemosphere.2020.128675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/08/2020] [Accepted: 10/16/2020] [Indexed: 06/12/2023]
Abstract
Metal contaminants in Antarctic soils are typically found around research stations which are concentrated in ice-free coastal areas. The risk of these contaminants to the Antarctic environment is not well understood, given Antarctica's unique organisms and climate. This study assessed the use of diffusive gradients in thin-films (DGT), a passive sampler that measures fluxes of labile metals from soils to porewaters, in Antarctic soils. DGT-labile measurements were compared to three chemical extractants of increasing strength including high-purity water, dilute acid (1 M HCl), and concentrated acids (3:1 v/v HNO3:HCl), to understand differences in contaminant geochemistry that may affect environmental risk. One site had high lead concentrations measured with dilute (114 ± 4 mg kg-1) and concentrated (150 ± 10 mg kg-1) acids, while DGT-labile concentrations were below the method detection limit (0.5 μg L-1), indicating that the lead species has low solubility or lability. Another site had low concentrations of zinc measured by dilute (36.2 ± 0.5 mg kg-1) or concentrated (76 ± 6 mg kg-1) acid extracts, but had high DGT-labile concentrations (350 ± 80 μg L-1). This reflects an active source of zinc supplied from soil to pore water over time. Copper was found to be acid extractable, water-soluble, and DGT-labile, with DGT-labile concentrations of up to 12 μg L-1. Despite the soil and metal-specific geochemical differences, any of the extracts could be used with statistical clustering techniques to identify differences in sites with elevated metal concentrations. This study shows that the DGT-method can identify contaminated sites comparably to chemical extracts but provides environmentally relevant measurements of metal contaminant lability in Antarctic soils.
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Affiliation(s)
- Darren J Koppel
- Faculty of Science, University of Technology Sydney, NSW, Australia; Faculty of Science Medicine and Health, University of Wollongong, NSW, Australia; CSIRO Land and Water, Lucas Heights, NSW, Australia.
| | - Gwilym Av Price
- Faculty of Science, University of Technology Sydney, NSW, Australia; CSIRO Land and Water, Lucas Heights, NSW, Australia
| | - Kathryn E Brown
- Australian Antarctic Division, Kingston, Tasmania, Australia
| | | | | | - Damian B Gore
- Department of Earth and Environmental Sciences, Macquarie University, NSW, Australia
| | - Dianne F Jolley
- Faculty of Science Medicine and Health, University of Wollongong, NSW, Australia; CSIRO Land and Water, Lucas Heights, NSW, Australia
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Signal Decoding for Glutamate Modulating Egg Laying Oppositely in Caenorhabditis elegans under Varied Environmental Conditions. iScience 2020; 23:101588. [PMID: 33089099 PMCID: PMC7567941 DOI: 10.1016/j.isci.2020.101588] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 08/07/2020] [Accepted: 09/16/2020] [Indexed: 11/24/2022] Open
Abstract
Animals' ability to sense environmental cues and to integrate this information to control fecundity is vital for continuing the species lineage. In this study, we observed that the sensory neurons Amphid neuron (ASHs and ADLs) differentially regulate egg-laying behavior in Caenorhabditis elegans under varied environmental conditions via distinct neuronal circuits. Under standard culture conditions, ASHs tonically release a small amount of glutamate and inhibit Hermaphrodite specific motor neuron (HSN) activities and egg laying via a highly sensitive Glutamate receptor (GLR)-5 receptor. In contrast, under Cu2+ stimulation, ASHs and ADLs may release a large amount of glutamate and inhibit Amphid interneuron (AIA) interneurons via low-sensitivity Glutamate-gated chloride channel (GLC)-3 receptor, thus removing the inhibitory roles of AIAs on HSN activity and egg laying. However, directly measuring the amount of glutamate released by sensory neurons under different conditions and assaying the binding kinetics of receptors with the neurotransmitter are still required to support this study directly. Short-term exposure of CuSO4 evokes hyperactive egg laying ASHs inhibit HSNs and egg laying via GLR-5 receptor under no Cu2+ treatment AIA interneurons suppress HSNs and thus egg laying through ACR-14 signaling Under noxious Cu2+ treatment, ASHs and ADLs suppress AIAs and augment egg laying
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