A1 Journal article (refereed)
Ecosystem responses to increased organic carbon concentration : comparing results based on long-term monitoring and whole-lake experimentation (2019)
Kankaala, P., Arvola, L., Hiltunen, M., Huotari, J., Jones, R. I., Nykänen, H., Ojala, A., Olin, M., Peltomaa, E., Peura, S., Rask, M., Tulonen, T., & Vesala, S. (2019). Ecosystem responses to increased organic carbon concentration : comparing results based on long-term monitoring and whole-lake experimentation. Inland Waters, 9(4), 489-502. https://doi.org/10.1080/20442041.2019.1600938
JYU authors or editors
Publication details
All authors or editors: Kankaala, Paula; Arvola, Lauri; Hiltunen, Minna; Huotari, Jussi; Jones, Roger I.; Nykänen, Hannu; Ojala, Anne; Olin, Mikko; Peltomaa, Elina; Peura, Sari; et al.
Journal or series: Inland Waters
ISSN: 2044-2041
eISSN: 2044-205X
Publication year: 2019
Volume: 9
Issue number: 4
Pages range: 489-502
Publisher: Taylor & Francis
Publication country: United Kingdom
Publication language: English
DOI: https://doi.org/10.1080/20442041.2019.1600938
Publication open access: Not open
Publication channel open access:
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/66467
Publication is parallel published: https://erepo.uef.fi/handle/123456789/7784
Abstract
Recent increases in terrestrial dissolved organic carbon (DOC) concentrations in northern inland waters have many ecological consequences. We examined available data on carbon cycles and food webs of 2 boreal headwater lakes in southern Finland. Basic limnology and catchment characteristics of a pristine lake, Valkea-Kotinen (VK), were monitored over the past 25 years while the lake has undergone browning and DOC increased from ∼11 to 13 mg L−1. Pronounced changes in the early 2000s represent a regime shift in DOC concentration and color. Lake Alinen Mustajärvi (AM) was manipulated for 2 years by additions of labile DOC (cane sugar), raising the DOC concentration from ∼10 to 12 mg L−1, but not changing light conditions. The 2 different approaches both revealed increased concentrations and efflux of carbon dioxide (CO2) from the lakes and thus net heterotrophy and changes in the pelagic community structure following an increase in DOC concentration. Long-term monitoring of VK revealed a decline in phytoplankton primary production (PP) along with browning, which was reflected in retarded growth of young (1–2-year-old) perch. In the experimentally manipulated lake (AM), PP was not affected, and the growth of young perch was more variable. The results suggested the importance of a pathway from labile DOC via benthic invertebrates to perch. Although provided with this extra resource, the food chain based on DOC proved inefficient. Long-term monitoring and whole-lake experimentation are complementary approaches for revealing how freshwater ecosystems respond to climate and/or atmospheric deposition-induced changes, such as browning.
Keywords: ecosystems (ecology); lakes; organic substances; carbon
Free keywords: ecosystem responses; organic carbon concentration
Contributing organizations
Ministry reporting: Yes
Reporting Year: 2019
JUFO rating: 1