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Wang T, Yang X, Li Z, Chen W, Wen X, He Y, Ma C, Yang Z, Zhang C. MeHg production in eutrophic lakes: Focusing on the roles of algal organic matter and iron-sulfur-phosphorus dynamics. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131682. [PMID: 37270963 DOI: 10.1016/j.jhazmat.2023.131682] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/20/2023] [Accepted: 05/21/2023] [Indexed: 06/06/2023]
Abstract
The mechanisms by which eutrophication affects methylmercury (MeHg) production have not been comprehensively summarized, which hinders accurately predicting the MeHg risk in eutrophic lakes. In this review, we first discussed the effects of eutrophication on biogeochemical cycle of mercury (Hg). Special attentions were paid to the roles of algal organic matter (AOM) and iron (Fe)-sulfur (S)-phosphorus (P) dynamics in MeHg production. Finally, the suggestions for risk control of MeHg in eutrophic lakes were proposed. AOM can affect in situ Hg methylation by stimulating the abundance and activities of Hg methylating microorganisms and regulating Hg bioavailability, which are dependent on bacteria-strain and algae species, the molecular weight and composition of AOM as well as environmental conditions (e.g., light). Fe-S-P dynamics under eutrophication including sulfate reduction, FeS formation and P release could also play crucial but complicated roles in MeHg production, in which AOM may participate through influencing the dissolution and aggregation processes, structural order and surface properties of HgS nanoparticles (HgSNP). Future studies should pay more attention to the dynamics of AOM in responses to the changing environmental conditions (e.g., light penetration and redox fluctuations) and how such variations will subsequently affect MeHg production. The effects of Fe-S-P dynamics on MeHg production under eutrophication also deserve further investigations, especially the interactions between AOM and HgSNP. Remediation strategies with lower disturbance, greater stability and less cost like the technology of interfacial O2 nanobubbles are urgent to be explored. This review will deepen our understanding of the mechanisms of MeHg production in eutrophic lakes and provide theoretical guidance for its risk control.
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Affiliation(s)
- Tantan Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Xu Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Zihao Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Wenhao Chen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Xin Wen
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Yubo He
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Chi Ma
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Zhongzhu Yang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China
| | - Chang Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China.
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AŽdajić M, Yumvihoze E, Blais JM, Poulain AJ. The effect of legacy gold mining on methylmercury cycling and microbial community structure in northern freshwater lakes. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:1220-1230. [PMID: 34318847 DOI: 10.1039/d1em00129a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Smelting activities at Giant Mine (Yellowknife, NWT, Canada) have resulted in high sulfate and arsenic concentrations in nearby lakes. Here we tested whether historic smelting affects current mercury (Hg) cycling in 35 freshwater lakes over a 2800 km2 area around the former gold mine. We sampled lake water and sediment over three consecutive years (2015-2017) using a factorial sampling design that accounted for different environmental variables known to affect the net methylmercury (MeHg) levels in water. Stable Hg(ii) and MeHg isotope tracers were used to quantify Hg methylation and demethylation rate constants in sediments, and 16S rRNA gene amplicon sequencing was used to characterize microbial community structure. This study reveals that the fraction of methylated total Hg (% MeHg) found in surface water is positively correlated to the sulfate gradient, while the rate at which Hg is methylated (Km) in sediments is negatively correlated with total arsenic, and positively correlated with dissolved organic carbon, total phosphorous, and % MeHg in the water. Furthermore, 6 of the 28 lakes that had detectable demethylation rate constants (Kd) also had significantly lower DOC concentrations than lakes with non-detectable Kd. Our results also show that legacy pollution from smelting activities is affecting the structure of microbial communities in lake sediments. This study reveals the complex dynamics of Hg cycling in this northern environment, highlighting the importance of large-scale studies in which the effect of multiple pollution gradients (e.g. arsenic and sulfate) must be taken into consideration.
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Affiliation(s)
- Mija AŽdajić
- Department of Biology, University of Ottawa, 30 Marie-Curie, Ottawa, Ontario K1N 6N5, Canada.
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Xu Z, Wu S, Christie P, Gao X, Xu J, Xu S, Liang P. Impacts of estuarine dissolved organic matter and suspended particles from fish farming on the biogeochemical cycling of mercury in Zhoushan island, eastern China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135921. [PMID: 31818602 DOI: 10.1016/j.scitotenv.2019.135921] [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: 10/11/2019] [Revised: 12/01/2019] [Accepted: 12/02/2019] [Indexed: 06/10/2023]
Abstract
Changes in the biogeochemical cycling of mercury (Hg) and Hg species were investigated in a typical marine aquaculture area located at Zhoushan island, Zhejiang province, east China. Mercury species were analyzed in different environmental samples collected during a field survey and a simulation batch experiment. The field work comprised both summer and winter collection of water and sediment samples from marine aquaculture sites (MAS) in a field survey and from corresponding reference sites (CRS) located 2500 m from the MAS. THg concentrations in water were 91.3 ± 70.3 and 115 ± 22.6 pmol L-1 in summer and winter, respectively. Particulate Hg accounting for ˃60% of THg and positively correlated with total suspended solid content in water. Dissolved organic carbon in water was positively correlated with dissolved Hg. Significantly higher (p < 0.001, F = 102) total methylmercury (TMeHg) contents were observed in MAS (0.31 ± 0.26 ng g-1) than in CRS (0.06 ± 0.03 ng g-1) in the sediment solid phase. Moreover, MeHg formation rate in MAS was clearly higher than in CRS in the simulation experiment. Both the field survey and the simulation experiment highlighted the readier formation of MeHg in MAS than in CRS. TMeHg levels in blackhead seabream (Acanthopagrus schlegelii), red snapper (Lutjanus campechanus) and perch (Perca fluviatilis) were only 52.7 ± 5.74, 23.7 ± 2.51 and 24.3 ± 3.86 ng g-1, values significantly lower than the safety guideline (1000 ng g-1) established by the World Health Organization.
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Affiliation(s)
- Zhentao Xu
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China
| | - Shengchun Wu
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China; Zhejiang Province Key Laboratory of Soil Contamination and Bioremediation, Hangzhou 311300, China
| | - Peter Christie
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China
| | - Xuefei Gao
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China
| | - Jialin Xu
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China
| | - Su Xu
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China.
| | - Peng Liang
- School of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou 311300, Zhejiang Province, China; Zhejiang Province Key Laboratory of Soil Contamination and Bioremediation, Hangzhou 311300, China.
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Wang F, Outridge PM, Feng X, Meng B, Heimbürger-Boavida LE, Mason RP. How closely do mercury trends in fish and other aquatic wildlife track those in the atmosphere? - Implications for evaluating the effectiveness of the Minamata Convention. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 674:58-70. [PMID: 31003088 DOI: 10.1016/j.scitotenv.2019.04.101] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/07/2019] [Accepted: 04/08/2019] [Indexed: 05/28/2023]
Abstract
The Minamata Convention to reduce anthropogenic mercury (Hg) emissions entered into force in 2017, and attention is now focused on how to best monitor its effectiveness at reducing Hg exposure to humans. A key question is how closely Hg concentrations in the human food chain, especially in fish and other aquatic wildlife, will track the changes in atmospheric Hg that are expected to occur following anthropogenic emission reductions. We investigated this question by evaluating several regional groups of case studies where Hg concentrations in aquatic biota have been monitored continuously or intermittently for several decades. Our analysis shows that in most cases Hg time trends in biota did not agree with concurrent Hg trends in atmospheric deposition or concentrations, and the divergence between the two trends has become more apparent over the past two decades. An over-arching general explanation for these results is that the impact of changing atmospheric inputs on biotic Hg is masked by two factors: 1) The aquatic environment contains a large inventory of legacy emitted Hg that remains available for bio-uptake leading to a substantial lag in biotic response time to a change in external inputs; and 2) Biotic Hg trends reflect the dominant effects of changes in multi-causal, local and regional processes (e.g., aquatic or terrestrial biogeochemical processes, feeding ecology, climate) that control the speciation, bioavailability, and bio-uptake of both present-day and legacy emitted Hg. Globally, climate change has become the most prevalent contributor to the divergence. A wide range of biotic Hg outcomes can thus be expected as anthropogenic atmospheric Hg emissions decline, depending on how these processes operate on specific regions and specific organisms. Therefore, evaluating the effectiveness of the Minamata Convention will require biomonitoring of multiple species that represent different trophic and ecological niches in multiple regions of the world.
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Affiliation(s)
- Feiyue Wang
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
| | - Peter M Outridge
- Centre for Earth Observation Science, and Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; Geological Survey of Canada, Natural Resources Canada, 601 Booth St., Ottawa, ON K1A 0E8, Canada
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China
| | - Lars-Eric Heimbürger-Boavida
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
| | - Robert P Mason
- Department of Marine Sciences, University of Connecticut, 1080 Shennecossett Road, Groton, CT 06340, USA
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Xu Q, Zhao L, Wang Y, Xie Q, Yin D, Feng X, Wang D. Bioaccumulation characteristics of mercury in fish in the Three Gorges Reservoir, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 243:115-126. [PMID: 30172117 DOI: 10.1016/j.envpol.2018.08.048] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 08/12/2018] [Accepted: 08/16/2018] [Indexed: 06/08/2023]
Abstract
Newly constructed reservoirs were recognized as hotspot of mercury (Hg) methylation, and then methylmercury (MeHg) accumulation in food chains. The risk of elevated MeHg concentrations in fish is one of the most important concerns in newly constructed reservoirs. The Three Gorges Reservoir (TGR) is one of the largest reservoirs in the world. However, the distribution and bioaccumulation characteristics of Hg species within the food chains and its potential ecological risk in the TGR remain poorly understood. In this study, 264 fish individuals covering 18 species were collected from the TGR. Total mercury (THg) and MeHg concentrations in different organs (gill, heart, liver, muscle and swim bladder) of fish species were analyzed; the values of δ13C and δ15N in fish muscle were determined as well to reveal the biomagnification properties of Hg in food chains. Our results showed that concentrations of THg (0.5-272 ng g-1, w.w.) and MeHg (0.1-199 ng g-1, w.w.) in fish muscle from the TGR ubiquitously fall below the safe fish consumption limit on Hg recommended by WHO (500 ng g-1, w.w.) and the US-EPA Water Quality Criterion for MeHg (300 ng g-1, w.w.). The short food web jointly with the limited trophic magnification factor in the TGR explained the relatively low Hg concentrations in predators. Among the five fish organs, muscle represented the highest Hg concentrations, followed by heart, liver, swim bladder, and gill, suggesting that muscle has the highest ability to accumulate Hg compared to the other organs. More importantly, no discernible "reservoir effect" was observed in the TGR within the initial few years after impoundment due to its special eco-environment including: 1) neutral and slightly alkaline pH and low dissolved organic carbon of water, 2) less vegetation coverage in inundated areas, 3) simple food web.
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Affiliation(s)
- Qinqin Xu
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Lei Zhao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Yongmin Wang
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Qing Xie
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Deliang Yin
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Dingyong Wang
- College of Resources and Environment, Southwest University, Chongqing 400715, PR China; Chongqing Key Laboratory of Agricultural Resources and Environment, Chongqing 400716, PR China.
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6
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Jiang T, Bravo AG, Skyllberg U, Björn E, Wang D, Yan H, Green NW. Influence of dissolved organic matter (DOM) characteristics on dissolved mercury (Hg) species composition in sediment porewater of lakes from southwest China. WATER RESEARCH 2018; 146:146-158. [PMID: 30243058 DOI: 10.1016/j.watres.2018.08.054] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/20/2018] [Accepted: 08/25/2018] [Indexed: 06/08/2023]
Abstract
The origin and composition of dissolved organic matter (DOM) in porewater of lake sediments is intricate and decisive for fate of pollutants including mercury (Hg). While there are many reports on the relationship between dissolved organic carbon concentration (DOC) and mercury (Hg) concentrations in aquatic systems, there are few in which DOM compositional properties, that may better explain the fate of Hg, have been the focus. In this study, porewaters from sediments of three lakes, Caihai Lake (CH), Hongfeng Lake (HF) and Wujiangdu Lake (WJD), all located in southwest China, were selected to test the hypothesis that DOM optical properties control the fate of Hg in aquatic ecosystems. Porewater DOM was extracted and characterized by UV-Vis absorption and fluorescence spectroscopy. A two end-member (autochthonous and allochthonous DOM) mixing model was used to unveil the origin of DOM in porewaters of the three lakes. Our results show a higher input of terrestrial DOM in the pristine lake CH, as compared to lakes HF and WJD lakes, which were both influenced by urban environments and enriched in autochthonous DOM. While the relationships between the concentrations of DOC and the different chemical forms of Hg forms were quite inconsistent, we found important links between specific DOM components and the fate of Hg in the three lakes. In particular, our results suggest that allochthonous, terrestrial DOM inhibits Hg(II) availability for Hg methylating micro-organisms. In contrast, autochthonous DOM seems to have been stimulated MeHg formation, likely by enhancing the activity of microbial communities. Indeed, DOM biodegradation experiments revealed that differences in the microbial activity could explain the variation in the concentration of MeHg. While relationships between concentrations of DOC and Hg vary among different sites and provide little information about Hg cycling, we conclude that the transport and transformation of Hg (e.g. the methylation process) are more strongly linked to DOM chemical composition and reactivity.
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Affiliation(s)
- Tao Jiang
- Department of Environment Science and Engineering, College of Resources and Environment, Southwest University, Chongqing, 400716, China; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Andrea G Bravo
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish National Research Council (CSIC), Barcelona, 08034, Spain
| | - Ulf Skyllberg
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå SE-90183, Sweden
| | - Erik Björn
- Department of Chemistry, Umeå University, SE-901-87, Umeå, Sweden
| | - Dingyong Wang
- Department of Environment Science and Engineering, College of Resources and Environment, Southwest University, Chongqing, 400716, China
| | - Haiyu Yan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
| | - Nelson W Green
- School of Chemical and Biomolecular Engineering, Atlanta, GA, 30332, United States
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Emmerton CA, Cooke CA, Wentworth GR, Graydon JA, Ryjkov A, Dastoor A. Total Mercury and Methylmercury in Lake Water of Canada's Oil Sands Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:10946-10955. [PMID: 30229653 DOI: 10.1021/acs.est.8b01680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Increased delivery of mercury to ecosystems is a common consequence of industrialization, including in the Athabasca Oil Sands Region (AOSR) of Canada. Atmospheric mercury deposition has been studied previously in the AOSR; however, less is known about the impact of regional industry on toxic methylmercury (MeHg) concentrations in lake ecosystems. We measured total mercury (THg) and MeHg concentrations for five years from 50 lakes throughout the AOSR. Mean lake water concentrations of THg (0.4-5.3 ng L-1) and MeHg (0.01-0.34 ng L-1) were similar to those of other boreal lakes and <5% of all samples exceeded Provincial water quality guidelines. Lakes with the highest THg concentrations were found >100 km northwest of oil sands mines and received runoff from geological formations high in metals concentrations. MeHg concentrations were highest in those lakes, and in smaller productive lakes closer to oil sands mines. Simulated annual average direct deposition of THg to sampled lakes using an atmospheric chemical transport model showed <2% of all mercury deposited to sampled lakes was emitted from oil sands activities. Consequently, spatial patterns of mercury in AOSR lakes were likely most influenced by watershed and lake conditions, though mercury concentrations in these lakes may be perturbed with future development and climatic change.
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Affiliation(s)
- Craig A Emmerton
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | - Colin A Cooke
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | - Gregory R Wentworth
- Environmental Monitoring and Science Division , Alberta Environment and Parks , Edmonton , Alberta T5J 5C6, Canada
| | | | - Andrei Ryjkov
- Air Quality Research Division , Environment and Climate Change Canada , Dorval , Quebec H9P 1J3, Canada
| | - Ashu Dastoor
- Air Quality Research Division , Environment and Climate Change Canada , Dorval , Quebec H9P 1J3, Canada
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Liang P, Feng X, You Q, Gao X, Xu J, Wong M, Christie P, Wu SC. The effects of aquaculture on mercury distribution, changing speciation, and bioaccumulation in a reservoir ecosystem. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:25923-25932. [PMID: 28940142 DOI: 10.1007/s11356-017-0189-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 09/12/2017] [Indexed: 06/07/2023]
Abstract
A survey was conducted in a freshwater reservoir located in Guizhou province, south China, to investigate the influence of fish aquaculture activities on mercury (Hg) distribution, speciation change, and bioaccumulation. Water, sediment, and aquaculture fish samples were collected from aquaculture sites (AS) and the corresponding reference sites (RS). The results showed that total mercury (THg) concentration in overlying water in Wujiangdu reservoir reached 6.87 ± 14.9 ng L-1. THg concentration in a different layer follows the sequence: surface layer > bottom layer > three intermediate layers with significant difference. In addition, the total methylmercury (TMeHg) concentration in overlying water was 0.113 ± 0.211 ng L-1. The highest TMeHg was observed in the bottom layer. Both dissolved Hg (DHg) and dissolved methylmercury (DMeHg) accounted for more than 50% of THg and TMeHg in the top four layers of overlying water, respectively. In contrast, particulate Hg (PHg) and particulate methylmercury were the major portion of THg and TMeHg in bottom layer and reached to 67 and 58.7% of THg and TMeHg, respectively. Aquaculture activities were estimated to contribute an annual loading of approximately 69.8 ng g-1of THg yearly in the top 1 cm of sediment underneath the rafts due to unconsumed fish feed. The extra loading of THg in sediment may have potential to stimulate the release of Hg to the overlying water. Both DMeHg and DHg in sediment pore water and organic matter (OM) contents in the top 4 cm of AS were noticeably higher than RS, which indicated that the accumulation of OM due to aquaculture activities promoted MeHg production in the top surface of sediment pore water. No significant difference was noted between THg in RS (296 ± 104 ng g-1) and AS (274 ± 132 ng g-1) in the solid phase. In addition, the sediments were net sources of both MeHg and inorganic Hg. For Hg in fish tissues, THg and inorganic Hg (IHg) in the liver were significantly higher (THg: p < 0.001, F = 9.98; IHg: p < 0.001, F = 13.1) than those in the other organs. In contrast, MeHg concentration in the muscle was significantly higher than (p < 0.01, F = 4.83) that in the other organs.
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Affiliation(s)
- Peng Liang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, People's Republic of China
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, People's Republic of China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002, People's Republic of China.
| | - Qiongzhi You
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China
| | - Xuefei Gao
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China
| | - Jialin Xu
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China
| | - Minghung Wong
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, People's Republic of China
| | - Peter Christie
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China
| | - Sheng-Chun Wu
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, 311300, Zhejiang Province, People's Republic of China.
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Lan C, Chen J, Wang J, Guo J, Yu J, Yu P, Yang H, Liu Y. Application of Circular Bubble Plume Diffusers to Restore Water Quality in a Sub-Deep Reservoir. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14111298. [PMID: 29072625 PMCID: PMC5707937 DOI: 10.3390/ijerph14111298] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/19/2017] [Accepted: 10/22/2017] [Indexed: 11/27/2022]
Abstract
Circular bubble plume diffusers have been confirmed as an effective technology for the restoration of the deep water system, but have never been applied in sub-deep water system. In this study, circular bubble plume diffusers were used, for the first time, to restore water quality in the Aha Reservoir, a typical sub-deep reservoir in Southwest China. Axisymmetric intrusive gravity currents were formed with a horizontal radius of 250 m at the equilibrium depth and the intrusion of oxygen-enriched water occurred within the depth of 10–14 m, while thermal stratification remained intact. A total of 95% of the imported oxygen was dissolved, but most was consumed by organic matter and other reduced substances within the hypolimnion. The oxygen consumption of organic matter, NH4+ and remaining reduced materials, accounted for 41.4–52.5%, 25% and 13.3–24.4% of the total imported oxygen, respectively. Compared with the control sites, dissolved oxygen level in the hypolimnion increased 3–4 times, and concentrations of NH4+, total Fe and total Mn were reduced by 15.5%, 45.5% and 48.9%, respectively. A significant decrease in total phosphorus and nitrogen concentrations was observed in the experimental zone (0.04–0.02 mg/L and 1.9–1.7 mg/L, respectively). This indicates that circular bubble plumes have great potential for oxygenation of the hypolimnion and improving water quality in the sub-deep water system. Nevertheless, further efforts are needed to improve the discrete bubble model to elaborate the oxygen transmission dynamics and the plume formation processes in sub-deep water systems, incorporating oxygen consumption processes.
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Affiliation(s)
- Chen Lan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jingan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Jianyang Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Jia Yu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Pingping Yu
- College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, China.
| | - Haiquan Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Yong Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
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Zhao L, Guo Y, Meng B, Yao H, Feng X. Effects of damming on the distribution and methylation of mercury in Wujiang River, Southwest China. CHEMOSPHERE 2017; 185:780-788. [PMID: 28734214 DOI: 10.1016/j.chemosphere.2017.07.077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/09/2017] [Accepted: 07/15/2017] [Indexed: 06/07/2023]
Abstract
Newly built reservoirs are regarded as sensitive ecosystem for mercury (Hg) methylation. A comprehensive study was conducted to understand the influence of damming on the distribution and methylation of Hg within a river-reservoir ecosystem in Wujiang River Basin (WRB), Southwest China. Hg species in inflow-outflow rivers of six cascade reservoirs were analyzed each month during 2006. Mean concentrations of total Hg (THg) and methylmercury (MeHg) in river water in WRB were 3.41 ± 1.98 ng L-1 and 0.15 ± 0.06 ng L-1, respectively. THg and particulate Hg (PHg) concentrations in outflow rivers of reservoirs significantly decreased after dam construction, suggesting that a considerable amount of PHg was intercepted by way of sedimentation. However, the influence of damming on the distributions of dissolved Hg (DHg) and reactive Hg (RHg) in rivers was less pronounced. MeHg concentrations in outflow rivers of the older reservoirs significantly increased compared to inflow rivers with the maximum increasing factor of 92%, indicating the active net Hg methylation in the reservoirs. However, the difference between MeHg in inflow rivers and outflow rivers were less pronounced in the newly constructed reservoirs, indicating that these reservoirs were not active sites of Hg methylation. The construction of the cascade reservoirs resulted in the elevation of MeHg in several sections of the Wujiang River, which attributed to the net Hg methylation in reservoirs and discharge of MeHg from hypolimnion. MeHg-enriched water in outflow rivers from hypolimnetic water could be transported to downstream, posing potential threat to the aquatic food web and human health.
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Affiliation(s)
- Lei Zhao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Yanna Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; PowerChina Guiyang Engineering Corporation Limited, Guiyang 550081, PR China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China.
| | - Heng Yao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China.
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Noh S, Kim CK, Kim Y, Lee JH, Han S. Assessing correlations between monomethylmercury accumulation in fish and trophic states of artificial temperate reservoirs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 580:912-919. [PMID: 28012652 DOI: 10.1016/j.scitotenv.2016.12.039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/02/2016] [Accepted: 12/04/2016] [Indexed: 06/06/2023]
Abstract
We investigated monomethylmercury (MMHg) concentrations in 448 samples of four common fish species (barbel steed, largemouth bass, leopard mandarin, and bluegill) and the trophic states of 14 artificial reservoirs in South Korea in order to understand how trophic states of reserviors affect MMHg concentrations in fish. The trophic state index (TSI) of each reservoir was determined using empirical equations based on the monthly chlorophyll-a, total phosphorus, and Secchi depth, collected over a three-year period. The length-normalized MMHg concentrations in fish showed a negative correlation with the TSI based on chlorophyll-a (r2=0.90) and total phosphorus (r2=0.75) that may be a result of particle dilution of MMHg in surface waters. This study revealed that MMHg accumulation in fish was better correlated with TSI than MMHg in water, therefore, we suggest that the measurement of TSI based on chlorophyll-a and total phosphorus is an effective way to predict MMHg bioaccumulation across diverse reservoirs.
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Affiliation(s)
- Seam Noh
- Division of Chemical Research, National Institute of Environmental Research (NIER), Incheon, Republic of Korea; School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Chan-Kook Kim
- Environmental Health & Safety Research Institute, EH R&C Co., Ltd., Bucheon, Republic of Korea
| | - Younghee Kim
- Division of Chemical Research, National Institute of Environmental Research (NIER), Incheon, Republic of Korea
| | - Jong-Hyeon Lee
- Environmental Health & Safety Research Institute, EH R&C Co., Ltd., Bucheon, Republic of Korea.
| | - Seunghee Han
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea.
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Liang P, Gao X, You Q, Zhang J, Cao Y, Zhang C, Wong MH, Wu SC. Role of mariculture in the loading and speciation of mercury at the coast of the East China Sea. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 218:1037-1044. [PMID: 27613319 DOI: 10.1016/j.envpol.2016.08.055] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/03/2016] [Accepted: 08/23/2016] [Indexed: 06/06/2023]
Abstract
The effects of mariculture on mercury (Hg) contamination and speciation in water, sediment and cultured fish in a typical mariculture zone located in Xiangshan bay, Zhejiang province, east China, were studied. Water, sediment and fish samples were collected from mariculture sites (MS) and from corresponding reference sites (RS) 2500 m away from the MS. The THg concentration in overlying water in Xiangshan bay reached as high as 16.6 ± 19.5 ng L-1, indicating that anthropogenic sources in this bay may contribution on Hg contamination in overlying water. Mariculture activities resulted in an increase in THg concentration in water from surface and bottom layers, which may be attributed to the discharge of domestic sewage and the accumulation of unconsumed fish feed and fish excreta in the benthic environment. Methylmercury (MeHg) concentrations in the bottom layer of overlying water and top surface layer of porewater underneath MS were higher than at RS, implying that mariculture activities promote Hg methylation in the interface between sediments and water. In addition, the concentrations of MeHg in sediment and porewater were significantly higher in summer than winter. It was observed that THg and MeHg contents in the muscle of blackhead seabream (Acanthopagrus schlegelii) (fed by the trash fish) were significantly higher (p < 0.001) than those in red snapper (Lutjanus campechanus) or perch (Perca fluviatilis) (fed by pellet fish feed). The THg and MeHg concentrations in the fish meat were closely related to the feeding mode, which indicate that fish feed rather than environmental media is the major pathway for Hg accumulation in fish muscle.
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Affiliation(s)
- Peng Liang
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Lin'an, Zhejiang Province 311300, China; Department of Science and Environmental Studies, The Hong Kong University of Education, Tai Po, Hong Kong Special Administrative Region
| | - Xuefei Gao
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China
| | - Qiongzhi You
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China
| | - Jin Zhang
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Lin'an, Zhejiang Province 311300, China
| | - Yucheng Cao
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Lin'an, Zhejiang Province 311300, China
| | - Chan Zhang
- College of Law and Political Science, Zhejiang Agriculture and Forestry University, Lin'an, Zhejiang Province 311300, China
| | - Ming-Hung Wong
- Department of Science and Environmental Studies, The Hong Kong University of Education, Tai Po, Hong Kong Special Administrative Region
| | - Sheng-Chun Wu
- School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province 311300, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Lin'an, Zhejiang Province 311300, China.
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Lucotte M, Paquet S, Moingt M. Climate and Physiography Predict Mercury Concentrations in Game Fish Species in Quebec Lakes Better than Anthropogenic Disturbances. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:710-723. [PMID: 26825460 DOI: 10.1007/s00244-016-0261-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 01/11/2016] [Indexed: 06/05/2023]
Abstract
The fluctuations of mercury levels (Hg) in fish consumed by sport fishers in North-Eastern America depend upon a plethora of interrelated biological and abiological factors. To identify the dominant factors ultimately controlling fish Hg concentrations, we compiled mercury levels (Hg) during the 1976-2010 period in 90 large natural lakes in Quebec (Canada) for two major game species: northern pike (Esox lucius) and walleye (Sander vitreus). Our statistical analysis included 28 geographic information system variables and 15 climatic variables, including sulfate deposition. Higher winter temperatures explained 36% of the variability in higher walleye growth rates, in turn accounting for 54% of the variability in lower Hg concentrations. For northern pike, the dominance of a flat topography in the watershed explained 31% of the variability in lower Hg concentrations. Higher mean annual temperatures explained 27% of the variability in higher pike Hg concentrations. Pelagic versus littoral preferred habitats for walleye and pike respectively could explain the contrasted effect of temperature between the two species. Heavy logging could only explain 2% of the increase in walleye Hg concentrations. The influence of mining on fish Hg concentrations appeared to be masked by climatic effects.
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Affiliation(s)
- Marc Lucotte
- Institute of Environmental Sciences and GEOTOP, University of Quebec at Montreal, P.O. Box 8888, Centre-Ville Station, Montreal, QC, H3C 3P8, Canada
| | - Serge Paquet
- Institute of Environmental Sciences and GEOTOP, University of Quebec at Montreal, P.O. Box 8888, Centre-Ville Station, Montreal, QC, H3C 3P8, Canada
| | - Matthieu Moingt
- Institute of Environmental Sciences and GEOTOP, University of Quebec at Montreal, P.O. Box 8888, Centre-Ville Station, Montreal, QC, H3C 3P8, Canada.
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Ma M, Wang D, Sun T, Zhao Z, Du H. Forest runoff increase mercury output from subtropical forest catchments: an example from an alpine reservoir in a national nature reserve (southwestern China). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:2745-2756. [PMID: 25205157 DOI: 10.1007/s11356-014-3549-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 09/01/2014] [Indexed: 06/03/2023]
Abstract
For a typical alpine forest reservoir that does not have other obvious mercury pollution sources, mercury levels in its downstream water can reflect the characteristics of mercury inputs and risks of a remote forest. To confirm this proposal, eight sampling campaigns were carried out in 2012 and 2013 to investigate the distribution patterns of Hg species in the water column and sediment profiles at four sampling stations in an alpine forest reservoir, southwestern China. The concentrations of total Hg (THg) and methylmercury (MeHg) in water samples of DaHong Reservoir varied from 2.8 to 8.2 ng L(-1) and 0.06 to 2.9 ng L(-1), respectively. The concentrations of these Hg species in the wet seasons (summer and fall) were significantly higher than those in the dry season (winter and spring). Forest field runoff and diffusion of Hg from sediments could be the reasons for elevated concentrations of these Hg species in the wet season. Elevated MeHg concentrations in water samples from the bottom water and water-sediment interface demonstrated an active net Hg methylation in the downstream of DaHong (DH) Reservoir. Dissolved MeHg levels in the pore water of surface sediments and the bottom of downstream were apparently higher than those in the upstream, which indicated that MeHg sources of sediment pore water varied in space. MeHg diffusive fluxes from sediment to overlying water were higher in the wet season than those in the dry season, demonstrating that high temperatures favor Hg methylation processes in sediment.
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Affiliation(s)
- Ming Ma
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China
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15
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Qiu G, Feng X, Jiang G. Synthesis of current data for Hg in areas of geologic resource extraction contamination and aquatic systems in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2012; 421-422:59-72. [PMID: 22221874 DOI: 10.1016/j.scitotenv.2011.09.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 09/04/2011] [Accepted: 09/06/2011] [Indexed: 05/15/2023]
Abstract
China has become the largest contributor of anthropogenic atmospheric mercury (Hg) in the world owing to its fast growing economy and the largest of populations. Over the last two decades, Hg has become of increasing environmental concern in China and much has been published on its distribution, transportation, methylation, and bioaccumulation in aquatic systems and areas of geologic resource extraction contaminated sites, such as coal-fired power plants, non-ferrous smelters, Hg mining and retorting sites, Au amalgam, landfills, chemical plants, etc.. Environmental compartments, like soil, water, air, and crop from areas of geologic resource extraction contamination, especially from Hg mining regions, exhibit elevated values of total-Hg and MMHg. Risk assessments indicate that the consumption of rice, which has a high bioaccumulation of MMHg, has become the dominant pathway of MMHg exposure of inhabitants living in Hg mining areas. Low concentrations less than 5ngl(-1) in total-Hg can be observed in rivers from remote areas, however, high concentrations that reached 1600ngl(-1) in total-Hg can be found in rivers from industrial and urban areas. The studies of hydropower reservoirs of southwest China indicated the old reservoirs act as net sinks for total-Hg and net sources of MMHg, while newly established ones act as net sinks for both total-Hg and MMHg, which is in sharp contrast to the evolution of biomethylation in reservoirs established in the boreal belt of North America and Eurasia. Fish from those reservoirs have relatively low levels of total-Hg, which do not exceed the maximum total-Hg limit of 0.5mgkg(-1) recommended by WHO. Currently, however, there is still a large data gap regarding Hg even in the areas mentioned above in China, which results in poor understanding of its environmental biogeochemistry. Moreover, for a better understanding of human and environmental health effects caused by the fast growing economy, long-term Hg monitoring campaigns are urgently needed.
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Affiliation(s)
- Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
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Fu X, Feng X, Wan Q, Meng B, Yan H, Guo Y. Probing Hg evasion from surface waters of two Chinese hyper/meso-eutrophic reservoirs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:5887-5896. [PMID: 20850866 DOI: 10.1016/j.scitotenv.2010.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 08/01/2010] [Accepted: 08/02/2010] [Indexed: 05/29/2023]
Abstract
Measurements of water/air exchange flux of gaseous elemental mercury (GEM) were conducted in a hyper-eutrophic reservoir and a meso-eutrophic reservoir in southwest China in both warm and cold seasons by using a dynamic flux chamber (DFC) method coupled with an automatic gaseous Hg analyzer. Both strong diurnal and seasonal variations of GEM fluxes were observed. The diurnal cycle of the GEM flux was more pronounced during sunny days compared to cloudy and rainy days, which highlights the effect of solar intensity on the GEM flux. GEM fluxes in warm seasons were considerably higher (2.5 to 4.1 times higher) than in cold seasons, which was attributed to the combined factors including meteorological factors, water quality parameters and water Hg concentrations. Clear variation in GEM fluxes was observed between the two reservoirs. Mean GEM fluxes in the hyper-eutrophic reservoir (WJD) (3.2-20.1 ng m(-2)h(-1)) were significantly higher than those in the meso-eutrophic reservoir (SFY) (0.6-4.4 ng m(-2)h(-1)). Evasion of Hg played a distinct role in the mass balance of Hg in the two reservoirs. In WJD, evasion was the second most important mechanism for Hg losses from the reservoir (17.5% of the total losses); whereas in SFY, loss of Hg via volatilization constituted an extremely little portion to the total losses of Hg (0.8%).
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Affiliation(s)
- Xuewu Fu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
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