Environmental and biological factors are joint drivers of mercury biomagnification in subarctic lake food webs along a climate and productivity gradient
Kozak, N., Ahonen, S. A., Keva, O., Østbye, K., Taipale, S. J., Hayden, B., & Kahilainen, K. K. (2021). Environmental and biological factors are joint drivers of mercury biomagnification in subarctic lake food webs along a climate and productivity gradient. Science of the Total Environment, 779, Article 146261. https://doi.org/10.1016/j.scitotenv.2021.146261
Published inScience of the Total Environment
© 2021 The Authors. Published by Elsevier B.V.
Subarctic lakes are getting warmer and more productive due to the joint effects of climate change and intensive land-use practices (e.g. forest clear-cutting and peatland ditching), processes that potentially increase leaching of peat- and soil-stored mercury into lake ecosystems. We sampled biotic communities from primary producers (algae) to top consumers (piscivorous fish), in 19 subarctic lakes situated on a latitudinal (69.0–66.5° N), climatic (+3.2 °C temperature and + 30% precipitation from north to south) and catchment land-use (pristine to intensive forestry areas) gradient. We first tested how the joint effects of climate and productivity influence mercury biomagnification in food webs focusing on the trophic magnification slope (TMS) and mercury baseline (THg baseline) level, both derived from linear regression between total mercury (log10THg) and organism trophic level (TL). We examined a suite of environmental and biotic variables thought to explain THg baseline and TMS with stepwise generalized multiple regression models. Finally, we assessed how climate and lake productivity affect the THg content of top predators in subarctic lakes. We found biomagnification of mercury in all studied lakes, but with variable TMS and THg baseline values. In stepwise multiple regression models, TMS was best explained by negative relationships with food chain length, climate-productivity gradient, catchment properties, and elemental C:N ratio of the top predator (full model R2 = 0.90, p < 0.001). The model examining variation in THg baseline values included the same variables with positive relationships (R2 = 0.69, p = 0.014). Mass-standardized THg content of a common top predator (1 kg northern pike, Esox lucius) increased towards warmer and more productive lakes. These results indicate that increasing eutrophication via forestry-related land-use activities increase the THg levels at the base of the food web and in top predators, suggesting these sources of nutrients and mercury should be considered in future bioaccumulation and biomagnification studies. ...
Publication in research information system
MetadataShow full item record
Additional information about fundingFunding was received from the Academy of Finland (projects 1140903, 1268566 to KKK), and Inland Norway University of Applied Sciences PhD scholarship for NK.
Showing items with similar title or keywords.
Mercury and amino acid content relations in northern pike (Esox lucius) in subarctic lakes along a climate-productivity gradient Kozak, Natalia; Kahilainen, Kimmo K.; Pakkanen, Hannu K.; Hayden, Brian; Østbye, Kjartan; Taipale, Sami J. (Elsevier, 2023)Mercury is a highly toxic element for consumers, but its relation to amino acids and physiology of wild fish is not well known. The main aim of this study was to evaluate how total mercury content (THg) of northern pike ...
Allochthony, fatty acid and mercury trends in muscle of Eurasian perch (Perca fluviatilis) along boreal environmental gradients Keva, Ossi; Kiljunen, Mikko; Hämäläinen, Heikki; Jones, Roger I.; Kahilainen, Kimmo K.; Kankaala, Paula; Laine, Miikka B.; Schilder, Jos; Strandberg, Ursula; Vesterinen, Jussi; Taipale, Sami J. (Elsevier, 2022)Environmental change, including joint effects of increasing dissolved organic carbon (DOC) and total phosphorus (TP) in boreal northern lakes could potentially affects food web energy sources and the biochemical composition ...
Land-use and climate related drivers of change in the reindeer management system in Finland : Geography of perceptions Rasmus, Sirpa; Wallen, Henri; Turunen, Minna; Landauer, Mia; Tahkola, Juho; Jokinen, Mikko; Laaksonen, Sauli (Elsevier BV, 2021)Drivers of change in the reindeer management system are rather well-known. But when developing the governance to support the traditional livelihoods, it is crucial to understand also practitioner perceptions. Systematic ...
Increasing temperature and productivity change biomass, trophic pyramids and community‐level omega‐3 fatty acid content in subarctic lake food webs Keva, Ossi; Taipale, Sami J.; Hayden, Brian; Thomas, Stephen M.; Vesterinen, Jussi; Kankaala, Paula; Kahilainen, Kimmo K. (Wiley-Blackwell, 2021)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 ...
Poor nutritional quality of primary producers and zooplankton driven by eutrophication is mitigated at upper trophic levels Taipale, Sami Johan; Ventelä, Anne‐Mari; Litmanen, Jaakko; Anttila, Lauri (John Wiley & Sons, 2022)Eutrophication and rising water temperature in freshwaters may increase the total production of a lake while simultaneously reducing the nutritional quality of food web components. We evaluated how cyanobacteria blooms, ...