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Ecomorphological divergence drives differential mercury bioaccumulation in polymorphic European whitefish (Coregonus lavaretus) populations of subarctic lakes.

https://arctichealth.org/en/permalink/ahliterature294218
Source
Sci Total Environ. 2017 Dec 01; 599-600:1768-1778
Publication Type
Journal Article
Date
Dec-01-2017
Author
Kimmo K Kahilainen
Stephen M Thomas
Elina K M Nystedt
Ossi Keva
Tommi Malinen
Brian Hayden
Author Affiliation
Department of Environmental Sciences, University of Helsinki, P.O. Box 65, FIN-00014, Finland; Kilpisjärvi Biological Station, Käsivarrentie 14622, FIN-99490 Kilpisjärvi, Finland. Electronic address: kimmo.kahilainen@helsinki.fi.
Source
Sci Total Environ. 2017 Dec 01; 599-600:1768-1778
Date
Dec-01-2017
Language
English
Publication Type
Journal Article
Keywords
Animals
Ecosystem
Food chain
Gills
Lakes - chemistry
Mercury - metabolism
Salmonidae - anatomy & histology - metabolism
Scandinavian and Nordic Countries
Water Pollutants, Chemical - metabolism
Abstract
Resource polymorphism, whereby ancestral trophic generalists undergo divergence into multiple specialist morphs, is common in salmonid fish populations inhabiting subarctic lakes. However, the extent to which such resource specialization into the three principal lake habitats (littoral, profundal, and pelagic) affects patterns of contaminant bioaccumulation remains largely unexplored. We assessed total mercury concentrations (THg) of European whitefish (Coregonus lavaretus (L.)) and their invertebrate prey in relation to potential explanatory variables across 6 subarctic lakes, of which three are inhabited by polymorphic (comprised of four morphs) and three by monomorphic populations. Among invertebrate prey, the highest THg concentrations were observed in profundal benthic macroinvertebrates, followed by pelagic zooplankton, with concentrations lowest in littoral benthic macroinvertebrates in both lake types. Broadly similar patterns were apparent in whitefish in polymorphic systems, where average age-corrected THg concentrations and bioaccumulation rates were the highest in pelagic morphs, intermediate in the profundal morph, and the lowest in the littoral morph. In monomorphic systems, age-corrected THg concentrations were generally lower, and showed pronounced lake-specific variation. In the polymorphic systems, we found significant relationships between whitefish muscle tissue THg concentration and gill raker count, resource use, lipid content and maximum length, whilst no such relationships were apparent in the monomorphic systems. Across all polymorphic lakes, the major variables explaining THg in whitefish were gill raker count and age, whereas in monomorphic systems, the factors were lake-specific. Whitefish resource polymorphism across the three main lake habitats therefore appears to have profound impacts on THg concentration and bioaccumulation rate. This highlights the importance of recognizing such intraspecific diversity in both future scientific studies and mercury monitoring programs.
PubMed ID
28545204 View in PubMed
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Ecomorphological divergence drives differential mercury bioaccumulation in polymorphic European whitefish (Coregonus lavaretus) populations of subarctic lakes.

https://arctichealth.org/en/permalink/ahliterature282913
Source
Sci Total Environ. 2017 May 20;599-600:1768-1778
Publication Type
Article
Date
May-20-2017
Author
Kimmo K Kahilainen
Stephen M Thomas
Elina K M Nystedt
Ossi Keva
Tommi Malinen
Brian Hayden
Source
Sci Total Environ. 2017 May 20;599-600:1768-1778
Date
May-20-2017
Language
English
Publication Type
Article
Abstract
Resource polymorphism, whereby ancestral trophic generalists undergo divergence into multiple specialist morphs, is common in salmonid fish populations inhabiting subarctic lakes. However, the extent to which such resource specialization into the three principal lake habitats (littoral, profundal, and pelagic) affects patterns of contaminant bioaccumulation remains largely unexplored. We assessed total mercury concentrations (THg) of European whitefish (Coregonus lavaretus (L.)) and their invertebrate prey in relation to potential explanatory variables across 6 subarctic lakes, of which three are inhabited by polymorphic (comprised of four morphs) and three by monomorphic populations. Among invertebrate prey, the highest THg concentrations were observed in profundal benthic macroinvertebrates, followed by pelagic zooplankton, with concentrations lowest in littoral benthic macroinvertebrates in both lake types. Broadly similar patterns were apparent in whitefish in polymorphic systems, where average age-corrected THg concentrations and bioaccumulation rates were the highest in pelagic morphs, intermediate in the profundal morph, and the lowest in the littoral morph. In monomorphic systems, age-corrected THg concentrations were generally lower, and showed pronounced lake-specific variation. In the polymorphic systems, we found significant relationships between whitefish muscle tissue THg concentration and gill raker count, resource use, lipid content and maximum length, whilst no such relationships were apparent in the monomorphic systems. Across all polymorphic lakes, the major variables explaining THg in whitefish were gill raker count and age, whereas in monomorphic systems, the factors were lake-specific. Whitefish resource polymorphism across the three main lake habitats therefore appears to have profound impacts on THg concentration and bioaccumulation rate. This highlights the importance of recognizing such intraspecific diversity in both future scientific studies and mercury monitoring programs.
PubMed ID
28545204 View in PubMed
Less detail

Increasing temperature and productivity change biomass, trophic pyramids and community-level omega-3 fatty acid content in subarctic lake food webs.

https://arctichealth.org/en/permalink/ahliterature304287
Source
Glob Chang Biol. 2021 Jan; 27(2):282-296
Publication Type
Journal Article
Date
Jan-2021
Author
Ossi Keva
Sami J Taipale
Brian Hayden
Stephen M Thomas
Jussi Vesterinen
Paula Kankaala
Kimmo K Kahilainen
Author Affiliation
Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
Source
Glob Chang Biol. 2021 Jan; 27(2):282-296
Date
Jan-2021
Language
English
Publication Type
Journal Article
Abstract
Climate change in the Arctic is outpacing the global average and land-use is intensifying due to exploitation of previously inaccessible or unprofitable natural resources. A comprehensive understanding of how the joint effects of changing climate and productivity modify lake food web structure, biomass, trophic pyramid shape and abundance of physiologically essential biomolecules (omega-3 fatty acids) in the biotic community is lacking. We conducted a space-for-time study in 20 subarctic lakes spanning a climatic (+3.2°C and precipitation: +30%) and chemical (dissolved organic carbon: +10 mg/L, total phosphorus: +45 µg/L and total nitrogen: +1,000 µg/L) gradient to test how temperature and productivity jointly affect the structure, biomass and community fatty acid content (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) of whole food webs. Increasing temperature and productivity shifted lake communities towards dominance of warmer, murky-water-adapted taxa, with a general increase in the biomass of primary producers, and secondary and tertiary consumers, while primary invertebrate consumers did not show equally clear trends. This process altered various trophic pyramid structures towards an hour glass shape in the warmest and most productive lakes. Increasing temperature and productivity had negative fatty acid content trends (mg EPA + DHA/g dry weight) in primary producers and primary consumers, but not in secondary nor tertiary fish consumers. The massive biomass increment of fish led to increasing areal fatty acid content (kg EPA + DHA/ha) towards increasingly warmer, more productive lakes, but there were no significant trends in other trophic levels. Increasing temperature and productivity are shifting subarctic lake communities towards systems characterized by increasing dominance of cyanobacteria and cyprinid fish, although decreasing quality in terms of EPA + DHA content was observed only in phytoplankton, zooplankton and profundal benthos.
PubMed ID
33124178 View in PubMed
Less detail

Increasing temperature and productivity change biomass, trophic pyramids and community-level omega-3 fatty acid content in subarctic lake food webs.

https://arctichealth.org/en/permalink/ahliterature311779
Source
Glob Chang Biol. 2021 Jan; 27(2):282-296
Publication Type
Journal Article
Date
Jan-2021
Author
Ossi Keva
Sami J Taipale
Brian Hayden
Stephen M Thomas
Jussi Vesterinen
Paula Kankaala
Kimmo K Kahilainen
Author Affiliation
Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
Source
Glob Chang Biol. 2021 Jan; 27(2):282-296
Date
Jan-2021
Language
English
Publication Type
Journal Article
Keywords
Animals
Biomass
Fatty Acids, Omega-3
Food chain
Lakes
Phytoplankton
Temperature
Abstract
Climate change in the Arctic is outpacing the global average and land-use is intensifying due to exploitation of previously inaccessible or unprofitable natural resources. A comprehensive understanding of how the joint effects of changing climate and productivity modify lake food web structure, biomass, trophic pyramid shape and abundance of physiologically essential biomolecules (omega-3 fatty acids) in the biotic community is lacking. We conducted a space-for-time study in 20 subarctic lakes spanning a climatic (+3.2°C and precipitation: +30%) and chemical (dissolved organic carbon: +10 mg/L, total phosphorus: +45 µg/L and total nitrogen: +1,000 µg/L) gradient to test how temperature and productivity jointly affect the structure, biomass and community fatty acid content (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) of whole food webs. Increasing temperature and productivity shifted lake communities towards dominance of warmer, murky-water-adapted taxa, with a general increase in the biomass of primary producers, and secondary and tertiary consumers, while primary invertebrate consumers did not show equally clear trends. This process altered various trophic pyramid structures towards an hour glass shape in the warmest and most productive lakes. Increasing temperature and productivity had negative fatty acid content trends (mg EPA + DHA/g dry weight) in primary producers and primary consumers, but not in secondary nor tertiary fish consumers. The massive biomass increment of fish led to increasing areal fatty acid content (kg EPA + DHA/ha) towards increasingly warmer, more productive lakes, but there were no significant trends in other trophic levels. Increasing temperature and productivity are shifting subarctic lake communities towards systems characterized by increasing dominance of cyanobacteria and cyprinid fish, although decreasing quality in terms of EPA + DHA content was observed only in phytoplankton, zooplankton and profundal benthos.
PubMed ID
33124178 View in PubMed
Less detail

Total mercury concentrations in liver and muscle of European whitefish (Coregonus lavaretus (L.)) in a subarctic lake - Assessing the factors driving year-round variation.

https://arctichealth.org/en/permalink/ahliterature290219
Source
Environ Pollut. 2017 Dec; 231(Pt 2):1518-1528
Publication Type
Journal Article
Date
Dec-2017
Author
Ossi Keva
Brian Hayden
Chris Harrod
Kimmo K Kahilainen
Author Affiliation
Department of Environmental Sciences, University of Helsinki, P.O.Box 65, FIN-00014, Finland. Electronic address: ossi.keva@helsinki.fi.
Source
Environ Pollut. 2017 Dec; 231(Pt 2):1518-1528
Date
Dec-2017
Language
English
Publication Type
Journal Article
Keywords
Animals
Arctic Regions
Environmental Monitoring - methods
Finland
Lakes - chemistry
Liver - chemistry - metabolism
Mercury - analysis
Muscles - chemistry - metabolism
Salmonidae - metabolism
Seasons
Water Pollutants, Chemical - analysis
Abstract
Subarctic lakes are characterised by extreme seasonal variation in light and temperature which influences growth, maturation, condition and resource use of fishes. However, our understanding of how seasonal changes affect mercury concentrations of fishes is limited. We conducted a year-round study (3 ice-covered months, 3 open-water months) with open-water inter-annual aspect (3 years: samples from August/September), focusing on total mercury (THg) concentrations and ecological characteristics of a common freshwater fish, European whitefish (Coregonus lavaretus (L.)) from a subarctic lake. We measured THg concentrations from tissues with fast (liver, n = 164) and moderate (muscle, n = 225) turnover rates, providing information on THg dynamics over different temporal scales. In both tissues, lipid-corrected THg concentrations were highest in winter (liver: 1.70 ± 0.88 µg/g, muscle: 0.24 ± 0.05 µg/g) and lowest in summer (liver: 0.87 ± 0.72 µg/g, muscle: 0.19 ± 0.04 µg/g). THg concentrations increased in winter following the summer-autumn dietary shift to pelagic zooplankton and starvation after spawning. Whitefish THg concentrations decreased towards summer, and were associated with consumption of benthic macroinvertebrates and subsequent growth dilution. Mercury bioaccumulated in both tissues with age, both showing the strongest regression slopes in winter and lowest in summer. THg concentrations in liver and muscle tissue were correlated throughout the year, however the correlation was lowest in summer, indicating high metabolism during somatic growing season in summer and growth dilution. Multiple linear regression models explained 50% and 55% of the THg variation in liver and muscle both models dominated by seasonally-variable factors i.e. sexual maturity, d13C, and condition factor. Seasonally varying bioaccumulation slopes and the higher level of intra-annual variation (21%) in whitefish THg concentration in muscle than the inter-annual accumulation (8%) highlight the importance of including seasonal factors in future THg studies.
PubMed ID
28923342 View in PubMed
Less detail