A1 Journal article (refereed)
Increasing temperature and productivity change biomass, trophic pyramids and community‐level omega‐3 fatty acid content in subarctic lake food webs (2021)
Keva, O., Taipale, S. J., Hayden, B., Thomas, S. M., Vesterinen, J., Kankaala, P., & Kahilainen, K. K. (2021). Increasing temperature and productivity change biomass, trophic pyramids and community‐level omega‐3 fatty acid content in subarctic lake food webs. Global Change Biology, 27(2), 282-296. https://doi.org/10.1111/gcb.15387
JYU authors or editors
Publication details
All authors or editors: Keva, Ossi; Taipale, Sami J.; Hayden, Brian; Thomas, Stephen M.; Vesterinen, Jussi; Kankaala, Paula; Kahilainen, Kimmo K.
Journal or series: Global Change Biology
ISSN: 1354-1013
eISSN: 1365-2486
Publication year: 2021
Publication date: 30/10/2020
Volume: 27
Issue number: 2
Pages range: 282-296
Publisher: Wiley-Blackwell
Publication country: United Kingdom
Publication language: English
DOI: https://doi.org/10.1111/gcb.15387
Publication open access: Not open
Publication channel open access:
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/72447
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.
Keywords: aquatic ecosystems; food webs; nutrients (animals and humans); omega fatty acids; climate changes; land use; silviculture; dissolved organic carbon
Free keywords: DOC; food web structure; forestry; land‐use; nutrients; omega‐3 HUFA; trophic level; trophic pyramid
Contributing organizations
Ministry reporting: Yes
Reporting Year: 2021
JUFO rating: 3