Environmental and biological factors are joint drivers of mercury biomagnification in subarctic lake food webs along a climate and productivity gradient

Autor: Sami J. Taipale, Salla A. Ahonen, Ossi Keva, Natalia Kozak, Kjartan Østbye, Brian Hayden, Kimmo K. Kahilainen
Přispěvatelé: Biological stations, Lammi Biological Station, Kilpisjärvi Biological Station
Jazyk: angličtina
Rok vydání: 2021
Předmět:
010504 meteorology & atmospheric sciences
Biomagnification
TROPHIC POSITION
maankäyttö
010501 environmental sciences
METHYLMERCURY
01 natural sciences
Food chain
Biological Factors
ONTARIO LAKES
CHAIN STRUCTURE
Climate change
ympäristömyrkyt
Waste Management and Disposal
Land-use
Apex predator
Trophic level
kalat
Stable isotopes
2. Zero hunger
FRESH-WATER
Ecology
Fishes
vesiekosysteemit
BIOACCUMULATION
selkärangattomat
Pollution
Subarctic climate
climate change
Productivity (ecology)
Environmental Monitoring
Food chain length
Environmental Engineering
Food Chain
elohopea
chemistry.chemical_element
stable isotopes
kasautuminen
WHITEFISH
land-use
Environmental Chemistry
Animals
ravintoketjut
Ecosystem
1172 Environmental sciences
0105 earth and related environmental sciences
fish
food chain length
Lake ecosystem
Mercury
15. Life on land
ilmastonmuutokset
CHARR SALVELINUS-ALPINUS
invertebrates
Invertebrates
Mercury (element)
Lakes
Fish
chemistry
isotooppianalyysi
13. Climate action
Environmental science
MARINE
Water Pollutants
Chemical
Zdroj: Science of the Total Environment
ISSN: 0048-9697
Popis: 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 degrees N), climatic (+3.2 degrees 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. 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 that the sources of nutrients and mercury should be considered in future bioaccumulation and biomagnification studies. (c) 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
Databáze: OpenAIRE
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