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Saqira S, Chariton A, Hose GC. Multiple stressors unpredictably affect primary producers and decomposition in a model freshwater ecosystem. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 347:123680. [PMID: 38467363 DOI: 10.1016/j.envpol.2024.123680] [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: 09/14/2023] [Revised: 02/11/2024] [Accepted: 02/27/2024] [Indexed: 03/13/2024]
Abstract
Freshwater ecosystems are affected by various stressors, such as contamination and exotic species, making them amongst the most imperilled biological systems on the planet. In Australia and elsewhere, copper is one of the most common metal contaminants in freshwater systems and the European carp (Cyprinus carpio L.) is one of the most pervasive and widespread invasive fish species. Copper (Cu) and carp can both directly affect primary production and decomposition, which are critical and interrelated nutrient cycling processes and ecosystem services. The aim of this study was to explore the direct and indirect effects of Cu and carp individually, and together on periphyton cover, chlorophyll a concentration, growth of the macrophyte Vallisneria spiralis L., and the decomposition of leaf litter and cotton strips in a controlled, factorial experiment in outdoor experimental ponds. In isolation, Cu reduced macrophyte growth and organic matter decomposition, while chlorophyll a concentrations and periphyton cover remained unchanged, possibly due to the Low-Cu concentrations in the overlying water. Carp addition alone had a direct negative effect on the biomass of aquatic plants outside protective cages, but also increased plant biomass inside the cages, periphyton cover and chlorophyll a concentrations. Leaf litter was more decomposed in the carp only ponds compared to controls, while there was no significant effect on cotton strip decomposition. Aquatic plants were absent in the Cu + carp ponds caused by the combined effects of Cu toxicity, carp disturbance and the increase in turbidity due to carp bioturbation. Increases in periphyton cover in Low-Cu + carp, while absence in the High-Cu + carp ponds, and differences in the decomposition of surface and buried cotton strips were not as predicted, which highlights the need for such studies to understand the complex interactions among stressors for environmental risk assessment.
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Affiliation(s)
- Sajida Saqira
- School of Natural Sciences, Macquarie University, NSW, 2109, Australia
| | - Anthony Chariton
- School of Natural Sciences, Macquarie University, NSW, 2109, Australia
| | - Grant C Hose
- School of Natural Sciences, Macquarie University, NSW, 2109, Australia.
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2
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Harford AJ, Simpson SL, Humphrey CL, Parry DL, Kumar A, Chandler L, Stauber JL, van Dam RA. Sediment spiking and equilibration procedures to achieve partitioning of uranium similar to contamination in tropical wetlands near a mine site. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 295:118673. [PMID: 34923059 DOI: 10.1016/j.envpol.2021.118673] [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: 08/29/2021] [Revised: 12/06/2021] [Accepted: 12/10/2021] [Indexed: 06/14/2023]
Abstract
The derivation of sediment quality guideline values (SQGVs) presents significant challenges. Arguably the most important challenge is to conduct toxicity tests using contaminated sediments with physico-chemistry that represents real-world scenarios. We used a novel metal spiking method for an experiment that ultimately aims to derive a uranium SQGV. Two pilot studies were conducted to inform the final spiking design, i.e. percolating a uranyl sulfate solution through natural wetland sediments. An initial pilot study that used extended mixing equilibration phases produced hardened sediments not representative of natural sediments. A subsequent percolation method produced sediment with similar texture to natural sediment and was used as the method for spiking the sediments. The range of total recoverable uranium (TR-U) concentrations achieved was 8-3200 mg/kg. This reflected the concentrations found in natural wetlands and water management ponds found on a uranium mine site and was above natural levels. Dilute-acid extractable uranium (AE-U) concentrations were >80% of total concentrations, indicating that much of the uranium in the spiked sediment was labile and potentially bioavailable. The portion of TR-U extractable as AE-U was similar at the start and end of the 4.5-month field-deployment. Porewater uranium (PW-U) analyses indicated that partition coefficients (Kd) were 2000-20,000 L/kg, and PW-U was greater in post- than pre-field-deployed samples when TR-U was ≤1500 mg/kg, indicating the binding became weaker during the field-deployment period. At higher spiked-U concentrations, the PW-U was lower post-field-deployment. Comparing the physico-chemical data of the spiked sediments with environmental monitoring data from sediments in the vicinity of a uranium mining operation indicated that they were representative of sediments contaminated by mining and that the U-spiked sediments had a clear U concentration gradient. This confirmed the suitability of the spiking procedure for preparing sediments that were suitable for deriving a SQGV for uranium.
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Affiliation(s)
- Andrew J Harford
- Environmental Research Institute of the Supervising Scientist (eriss), Department of Agriculture, Water and the Environment, Darwin, Northern Territory, Australia.
| | - Stuart L Simpson
- Centre for Environmental Contaminants Research, Water Quality Management, CSIRO Land and Water, Lucas Heights, New South Wales, Australia
| | - Christopher L Humphrey
- Environmental Research Institute of the Supervising Scientist (eriss), Department of Agriculture, Water and the Environment, Darwin, Northern Territory, Australia
| | - David L Parry
- Rio Tinto, PO Box 2470, Brisbane, Queensland, Australia
| | - Anu Kumar
- Environmental Assessment and Technologies, CSIRO Land and Water, Glen Osmond, South Australia, Australia
| | - Lisa Chandler
- Environmental Research Institute of the Supervising Scientist (eriss), Department of Agriculture, Water and the Environment, Darwin, Northern Territory, Australia
| | - Jennifer L Stauber
- Centre for Environmental Contaminants Research, Water Quality Management, CSIRO Land and Water, Lucas Heights, New South Wales, Australia
| | - Rick A van Dam
- Environmental Research Institute of the Supervising Scientist (eriss), Department of Agriculture, Water and the Environment, Darwin, Northern Territory, Australia; WQadvice, Adelaide, South Australia, Australia
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Cervi EC, Clark S, Boye KE, Gustafsson JP, Baken S, Burton GA. Copper transformation, speciation, and detoxification in anoxic and suboxic freshwater sediments. CHEMOSPHERE 2021; 282:131063. [PMID: 34111636 DOI: 10.1016/j.chemosphere.2021.131063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/19/2021] [Accepted: 05/28/2021] [Indexed: 06/12/2023]
Abstract
The complex chemistry of copper (Cu) in freshwater sediments at low concentrations is not well understood. We evaluated the transformation processes of Cu added to freshwater sediments under suboxic and anoxic conditions. Freshwater sediments from three sources in Michigan with different characteristics (Spring Creek, River Raisin, and Maple Lake) were spiked with 30 or 60 mg kg-1 Cu and incubated under a nitrogen atmosphere. After 28-d, each treatment subset was amended with organic matter (OM) to promote anoxic conditions and evaluate its effects on Cu speciation. OM addition triggered a shift from suboxic to anoxic conditions, and sequential extractions showed that Cu accordingly shifted from acid-soluble to oxidizable fractions. Extended X-ray absorption fine-structure (EXAFS) spectroscopy revealed that Cu sulfides dominated all anoxic samples except for Spring Creek 30 mg kg-1, where Cu(I) was predominantly complexed to thiol groups of OM. Covellite and chalcopyrite (CuFeS2) were the predominant Cu species in nearly all anoxic samples, as determined by Raman spectroscopy, scanning electron microscopy, and X-ray absorption near-edge structure (XANES) spectroscopy. Copper reduction also occurred under suboxic conditions: for two of three sediments, around 80% had been reduced to Cu(I), while the remaining 20% persisted as Cu(II) complexed to OM. However, in the third coarsest (i.e., Spring Creek), around 50% of the Cu had been reduced, forming Cu(I)-OM complexes, while the remainder was Cu(II)-OM complexes. Toxicity tests showed that survival of H. azteca and D. magna were significantly lower in suboxic treatments. Anoxic sediments triggered a near-complete transformation of Cu to sulfide minerals, reducing its toxicity.
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Affiliation(s)
- E C Cervi
- Golder Associates Brazil, Belo Horizonte, MG 30112-010, Brazil.
| | - S Clark
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI 48109, USA
| | - K E Boye
- Stanford Synchrotron Radiation Lightsource, SLAC National Laboratory, Menlo Park, CA 94025, USA
| | - J P Gustafsson
- Department of Soil and Environment, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - S Baken
- European Copper Institute, Brussels, B-1150, Belgium
| | - G A Burton
- School for Environment and Sustainability, University of Michigan, Ann Arbor, MI 48109, USA
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Thit A, Selck H. Biodynamics and adverse effects of CuO nanoparticles and CuCl 2 in the oligochaete T. tubifex: Cu form influence biodynamics in water, but not sediment. Nanotoxicology 2021; 15:673-689. [PMID: 34137642 DOI: 10.1080/17435390.2021.1913657] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The use of copper oxide (CuO) NPs results in the release of these particles into the aquatic environment. Here, the particles settle out and accumulate in the sediment. However, little is known about the biodynamics of sediment-associated NPs in benthic organisms. We compared the toxicity and biodynamics of CuO NPs (7 nm) and dissolved Cu (CuCl2) in the sediment-dwelling oligochaete, Tubifex tubifex, to gain insights into the relative importance of metal form (CuCl2 vs CuO NPs) and exposure route (water vs sediment). Isotopically enriched 65Cu was used as a tracer to distinguish background from newly accumulated 65Cu in worms. For each exposure route, we conducted three experiments: one uptake, one elimination, and one longer-term net accumulation experiment to parameterize uptake and elimination of 65CuCl2 and 65CuO NPs in T. tubifex. 65Cu accumulation was detected for both 65CuCl2 and 65CuO NPs regardless of whether T. tubifex were exposed in sediment- or water-only setups. Water exposures to 65CuCl2 resulted in tail trauma whereas limited effects were seen for sediment exposures or exposures to 65CuO NPs via either exposure route. Uptake rate constants and accumulation of 65Cu in T. tubifex were higher following 65CuCl2 exposure than 65CuO NPs, in water, but not in sediment. Thus, the relative importance of exposure route and Cu form for uptake dynamics is not straightforward suggesting that findings on bioaccumulation and toxicity in water exposures cannot be directly extrapolated to sediment.
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Affiliation(s)
- Amalie Thit
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - Henriette Selck
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
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Sutcliffe B, Hose GC, Harford AJ, Midgley DJ, Greenfield P, Paulsen IT, Chariton AA. Microbial communities are sensitive indicators for freshwater sediment copper contamination. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 247:1028-1038. [PMID: 30823331 DOI: 10.1016/j.envpol.2019.01.104] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 01/20/2019] [Accepted: 01/26/2019] [Indexed: 06/09/2023]
Abstract
Anthropogenic activities, such as mining and agriculture, have resulted in many freshwater systems having elevated concentrations of copper. Despite the prevalence of this contamination, and the vital ecological function of prokaryotes, just three studies have investigated prokaryote community responses to copper concentration in freshwater sediments. To address this, the current study investigated these communities in outdoor mesocosms spiked with varying copper concentrations. We profiled the prokaryotic communities at the taxonomic level, using next-generation high-throughput sequencing techniques, as well as their function, using baiting with leaf analogues, and Biolog Ecoplates for community-level physiological profiling. Sediments containing just 46 mg kg-1 of copper, had distinctly different microbial communities compared with controls, as determined by both DNA and RNA 16S ribosomal RNA gene (rRNA) profiling. In addition to this, sediment communities displayed a greatly reduced utilisation of carbon substrates under elevated copper, while the communities recruited onto leaf analogues were also disparate from those of control ponds. Given the vital role of prokaryotes in ecosystem processes, including carbon cycling, these changes are potentially of great ecological relevance, and are seen to occur well below the 'low risk' sediment quality guideline values (SQGV) used by regulatory bodies internationally.
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Affiliation(s)
- B Sutcliffe
- Macquarie University, Sydney, New South Wales, 2109, Australia; Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia.
| | - G C Hose
- Macquarie University, Sydney, New South Wales, 2109, Australia
| | - A J Harford
- Supervising Scientist Branch, Department of the Environment and Energy, Darwin, NT, Australia
| | - D J Midgley
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia
| | - P Greenfield
- Macquarie University, Sydney, New South Wales, 2109, Australia; Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia
| | - I T Paulsen
- Macquarie University, Sydney, New South Wales, 2109, Australia
| | - A A Chariton
- Macquarie University, Sydney, New South Wales, 2109, Australia.
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Guo Z, Ye H, Xiao J, Hogstrand C, Zhang L. Biokinetic Modeling of Cd Bioaccumulation from Water, Diet and Sediment in a Marine Benthic Goby: A Triple Stable Isotope Tracing Technique. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:8429-8437. [PMID: 29983045 DOI: 10.1021/acs.est.8b00027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Aquatic animals are often simultaneously exposed to metals through multiple routes in the natural environment. This study explored a triple stable isotope tracing method to quantify simultaneous cadmium (Cd) uptake biokinetics by yellow stripe goby from water (traced by 110Cd), sediment (traced by 111Cd), and diet (traced by 113Cd) when the fish were exposed to Cd for 24 h. The simultaneous uptake of Cd from multiple routes during 4 weeks was then predicted by the modified biokinetic model. The results demonstrated that the uptake rate constant of waterborne 110Cd, sediment-associated 111Cd, and dietary 113Cd was 3.1 L kg-1 d-1, 2.2 × 10-4 g g-1 d-1, and 3.3 × 10-3 g g-1 d-1 in the fish. Sedimentary Cd was less bioavailable than the waterborne and dietary Cd; however, sediment could become the predominant Cd source of the total Cd bioaccumulation when the partition coefficient of Cd between sediment and seawater ( Kd) is larger than 6 × 104 L kg-1. The simultaneous uptake of Cd from the three routes could be successfully predicted by the modified model. The model revealed that the Cd bioaccumulation generally increased with the increase of ambient Cd concentration in all the three routes. Overall, our findings demonstrated that the multiple stable isotopes tracing method and the modified biokinetic model have a wide generality and applicability for predicting Cd bioaccumulation under multiple routes of metal exposure scenario and may have application to other metals.
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Affiliation(s)
- Zhiqiang Guo
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology , Chinese Academy of Sciences , Guangzhou 510301 , China
- State Key Laboratory of Marine Resource Utilization in South China Sea, College of Marine Science , Hainan University , Haikou 570228 , China
| | - Hengzhen Ye
- State Key Laboratory of Marine Resource Utilization in South China Sea, College of Marine Science , Hainan University , Haikou 570228 , China
| | - Juan Xiao
- College of Food Science and Technology , Hainan University , Haikou 570228 , China
| | - Christer Hogstrand
- Metals Metabolism Group, School of Life Course Sciences , King's College London , 150 Stamford Street , London SE1 9NH , U.K
| | - Li Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology , Chinese Academy of Sciences , Guangzhou 510301 , China
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Sutcliffe B, Chariton AA, Harford AJ, Hose GC, Greenfield P, Midgley DJ, Paulsen IT. Diverse fungal lineages in subtropical ponds are altered by sediment-bound copper. FUNGAL ECOL 2018. [DOI: 10.1016/j.funeco.2018.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Willis BE, Bishop WM. Understanding Fate and Effects of Copper Pesticides in Aquatic Systems. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/gep.2016.45004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Thit A, Dybowska A, Købler C, Kennaway G, Selck H. Influence of copper oxide nanoparticle shape on bioaccumulation, cellular internalization and effects in the estuarine sediment-dwelling polychaete, Nereis diversicolor. MARINE ENVIRONMENTAL RESEARCH 2015; 111:89-98. [PMID: 26149327 DOI: 10.1016/j.marenvres.2015.06.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 06/09/2015] [Accepted: 06/15/2015] [Indexed: 06/04/2023]
Abstract
CuO nanoparticles (NPs) released into the aquatic environment will likely accumulate in the sediment. Here we synthesized and characterized CuO NPs with different shapes and thus sizes: spheres, rods and spindles. Nereis diversicolor were exposed for 10 days to control sediment or sediment spiked with CuO NPs or aqueous Cu (Cu-Aq, CuCl2) at 7, 70 and 140 μg Cu g(-1) dw sediment. Cu from all Cu treatments accumulated in worms in a concentration-dependent manner. Only Cu-Aq decreased burrowing, suggesting that worms avoid Cu when added to sediment as Cu-Aq, but not CuO NPs. Transmission Electron Microscopy of gut sections indicated limited presence of CuO NP-like objects in the gut lumen, but evidence on whether accumulated Cu from CuO NP exposure was internalized as particles was not conclusive. Overall, bioavailability and avoidance was not influenced by particle shape or size, whereas Cu form (Cu-Aq vs particulate) and exposure concentration had significant impact.
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Affiliation(s)
- Amalie Thit
- Dept. of Environmental, Social and Spatial Change, Roskilde University, Roskilde, Denmark.
| | | | - Carsten Købler
- Dept. of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark.
| | | | - Henriette Selck
- Dept. of Environmental, Social and Spatial Change, Roskilde University, Roskilde, Denmark.
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Ramskov T, Thit A, Croteau MN, Selck H. Biodynamics of copper oxide nanoparticles and copper ions in an oligochaete - Part I: Relative importance of water and sediment as exposure routes. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 164:81-91. [PMID: 25935103 DOI: 10.1016/j.aquatox.2015.04.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/18/2015] [Accepted: 04/21/2015] [Indexed: 06/04/2023]
Abstract
Copper oxide (CuO) nanoparticles (NPs) are widely used, and likely released into the aquatic environment. Both aqueous (i.e., dissolved Cu) and particulate Cu can be taken up by organisms. However, how exposure routes influence the bioavailability and subsequent toxicity of Cu remains largely unknown. Here, we assess the importance of exposure routes (water and sediment) and Cu forms (aqueous and nanoparticulate) on Cu bioavailability and toxicity to the freshwater oligochaete, Lumbriculus variegatus, a head-down deposit-feeder. We characterize the bioaccumulation dynamics of Cu in L. variegatus across a range of exposure concentrations, covering both realistic and worst-case levels of Cu contamination in the environment. Both aqueous Cu (Cu-Aq; administered as Cu(NO3)2) and nanoparticulate Cu (CuO NPs), whether dispersed in artificial moderately hard freshwater or mixed into sediment, were weakly accumulated by L. variegatus. Once incorporated into tissues, Cu elimination was negligible, i.e., elimination rate constants were in general not different from zero for either exposure route or either Cu form. Toxicity was only observed after waterborne exposure to Cu-Aq at very high concentration (305μgL(-1)), where all worms died. There was no relationship between exposure route, Cu form or Cu exposure concentration on either worm survival or growth. Slow feeding rates and low Cu assimilation efficiency (approximately 30%) characterized the uptake of Cu from the sediment for both Cu forms. In nature, L. variegatus is potentially exposed to Cu via both water and sediment. However, sediment progressively becomes the predominant exposure route for Cu in L. variegatus as Cu partitioning to sediment increases.
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Affiliation(s)
- Tina Ramskov
- Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde, Denmark; US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025, United States.
| | - Amalie Thit
- Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde, Denmark.
| | - Marie-Noële Croteau
- US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025, United States.
| | - Henriette Selck
- Department of Environmental, Social and Spatial Change, Roskilde University, PO Box 260, Universitetsvej 1, DK-4000 Roskilde, Denmark; US Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025, United States.
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Gardham S, Chariton AA, Hose GC. Direct and indirect effects of copper-contaminated sediments on the functions of model freshwater ecosystems. ECOTOXICOLOGY (LONDON, ENGLAND) 2015; 24:61-70. [PMID: 25261958 DOI: 10.1007/s10646-014-1355-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/18/2014] [Indexed: 06/03/2023]
Abstract
Copper is acutely toxic to, and directly affects, primary producers and decomposers, which are key players in essential processes such as the nutrient cycle in freshwater ecosystems. Even though the indirect effects of metals (for example effects due to changes in species interactions) may be more common than direct effects, little is known about the indirect effects of copper on primary producers and decomposers. The effects of copper on phytoplankton, macrophytes, periphyton and organic matter decomposition in an outdoor lentic mesocosm facility were assessed, and links between the responses examined. Copper directly decreased macrophyte growth, subsurface organic matter decomposition, and the potential for high phytoplankton Chlorophyll a concentrations. However, periphyton cover and organic matter decomposition on the surface of the sediment were stimulated by the presence of copper. These latter responses were attributed to indirect effects, due to a reduction in grazing pressure from snails, particularly Physa acuta, in the higher copper-contaminated mesocosms. This permitted the growth of periphyton and other heterotrophs, ultimately increasing decomposition at the sediment surface. The present study demonstrates the pronounced influence indirect effects may have on ecological function, findings that may not be observed in traditional laboratory studies (which utilize single species or simplistic communities).
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Affiliation(s)
- Stephanie Gardham
- Department of Environment and Geography, Macquarie University, Sydney, NSW, 2109, Australia,
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Gardham S, Chariton AA, Hose GC. Invertebrate community responses to a particulate- and dissolved-copper exposure in model freshwater ecosystems. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2014; 33:2724-2732. [PMID: 25143236 DOI: 10.1002/etc.2728] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/09/2014] [Accepted: 08/18/2014] [Indexed: 06/03/2023]
Abstract
Historical contamination has left a legacy of high copper concentrations in the sediments of freshwater ecosystems worldwide. Previous mesocosm studies have focused on dissolved-copper exposures in the overlying waters, which, because of altered exposure pathways, may not accurately predict the effects of copper exposure on invertebrate communities at historically contaminated sites. The present study assessed the effects of copper on the establishment of invertebrate communities within a large outdoor pond mesocosm facility containing environmentally relevant copper-spiked sediments. High particulate copper concentrations (>400 mg/kg dry wt) caused a pronounced effect on the benthic community richness, abundance, and structure in the mesocosms, but particulate copper concentrations below 100 mg/kg dry weight had no effect. Furthermore, there were no effects of copper on the invertebrate communities within the water column, even in the highest copper treatment. The response of the benthic community to copper was influenced by interspecific interactions, the stage of ecological succession, and interspecies variation in sensitivity to copper. The present study demonstrates the importance of using environmentally realistic exposure scenarios that provide both particulate and dissolved exposure pathways. It also emphasizes that risk assessments for aquatic ecosystems should consider the influence of interspecific interactions and interspecies variation in driving the biotic response to contamination.
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Affiliation(s)
- Stephanie Gardham
- Department of Environment and Geography, Macquarie University, New South Wales, Australia; Centre for Environmental Contaminants Research, Oceans and Atmosphere Flagship, CSIRO, New South Wales, Australia
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