uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Colored organic matter increases CO2 in meso-eutrophic lake water through altered light climate and acidity
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.ORCID iD: 0000-0002-0078-2810
Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.ORCID iD: 0000-0002-3082-8728
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.ORCID iD: 0000-0003-3509-8266
Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.ORCID iD: 0000-0002-9918-7789
Show others and affiliations
2019 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 64, no 2, p. 744-756Article in journal (Refereed) Published
Abstract [en]

Many surface waters across the boreal region are browning due to increased concentrations of colored allochthonous dissolved organic carbon (DOC). Browning may stimulate heterotrophic metabolism, may have a shading effect constraining primary production, and may acidify the water leading to decreased pH with a subsequent shift in the carbonate system. All these effects are expected to result in increased lake water carbon dioxide (CO2) concentrations. We tested here these expectations by assessing the effects of both altered allochthonous DOC input and light conditions through shading on lake water CO2 concentrations. We used two mesocosm experiments with water from the meso‐eutrophic Lake Erken, Sweden, to determine the relative importance of bacterial activities, primary production, and shifts in the carbonate system on CO2 concentrations. We found that DOC addition and shading resulted in a significant increase in partial pressure of CO2 (pCO2) in all mesocosms. Surprisingly, there was no relationship between bacterial activities and pCO2. Instead the experimental reduction of light by DOC and/or shading decreased the photosynthesis to respiration ratio leading to increased pCO2. Another driving force behind the observed pCO2 increase was a significant decrease in pH, caused by a decline in photosynthesis and the input of acidic DOC. Considering that colored allochthonous DOC may increase in a warmer and wetter climate, our results could also apply for whole lake ecosystems and pCO2 may increase in many lakes through a reduction in the rate of photosynthesis and decreased pH.

Place, publisher, year, edition, pages
2019. Vol. 64, no 2, p. 744-756
National Category
Oceanography, Hydrology and Water Resources
Identifiers
URN: urn:nbn:se:uu:diva-366220DOI: 10.1002/lno.11072ISI: 000461865500022OAI: oai:DiVA.org:uu-366220DiVA, id: diva2:1263908
Available from: 2018-11-18 Created: 2018-11-18 Last updated: 2020-03-09Bibliographically approved
In thesis
1. Carbon Dioxide in Inland Waters: Drivers and Mechanisms Across Spatial and Temporal Scales
Open this publication in new window or tab >>Carbon Dioxide in Inland Waters: Drivers and Mechanisms Across Spatial and Temporal Scales
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Inland waters are an essential component of the global carbon cycle as they are very active sites for carbon transformation processes. Much of this carbon is transformed into the greenhouse gas carbon dioxide (CO2) and emitted into the atmosphere. The biogeochemical and hydrological mechanisms driving CO2 concentrations in inland waters are manifold. Although some of them have been studied in detail, there are still knowledge gaps regarding the relative importance of the different CO2-driving mechanisms, both on a spatial and a temporal scale. The main aim of this thesis was to fill some of the knowledge gaps by studying long- and short-term effects of enhanced dissolved organic carbon (DOC) concentrations on surface water partial pressure of CO2 (pCO2) as well as to investigate both internal (i.e., within the water body) and external (i.e., catchment) drivers of pCO2 in inland waters. Based on analyses of long-term data from more than 300 boreal lakes and streams and on results from two mesocosm experiments as well as a detailed catchment study, one of the main results of the thesis was that DOC concentrations were, on a temporal scale, generally uncoupled to pCO2. Indeed, additions of allochthonous DOC to lake water could result in increased pCO2 in waters but not as originally expected by stimulation of bacterial activity but instead by light driven suppression of primary production, at least in mesotrophic waters. Changes in the carbonate system was also found to be a main driver for surface water pCO2. Finally, also external processes such as groundwater inputs contributed substantially to variations of surface water pCO2. In a detailed study on carbon in groundwater, pCO2 in groundwater was found to decrease with soil depth and correlated negatively with pH, which increased with soil depth. Conclusively, this thesis show that pCO2 does not follow the trends of increased DOC in boreal surface waters but instead correlates with changes in primary production and shifts in the carbonate system. Additionally, the dominating mechanisms driving pCO2 clearly differ between lakes and streams. Consequently, simulations of future CO2 dynamics and emissions from inland waters cannot rely on DOC concentrations as a pCO2 predictor, but rather need to incorporate several pCO2 driving mechanisms, and consider the difference between lakes and streams.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 50
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1838
Keywords
carbon dioxide, dissolved organic carbon, inland water, lake, stream, groundwater, mesocosm, carbonate system, carbon
National Category
Biological Sciences
Research subject
Biology with specialization in Limnology
Identifiers
urn:nbn:se:uu:diva-390882 (URN)978-91-513-0720-6 (ISBN)
Public defence
2019-10-04, Friessalen, Evolutionsbiologiskt Centrum, Norbyvägen 18, Uppsala, 09:30 (English)
Opponent
Supervisors
Available from: 2019-09-12 Created: 2019-08-15 Last updated: 2019-10-15

Open Access in DiVA

fulltext(667 kB)172 downloads
File information
File name FULLTEXT01.pdfFile size 667 kBChecksum SHA-512
6c069fdecc5aa36c6f537cebf5615757f8adb4c4b5123b39da7eedf5fa1d382ec48a2311adee9faec1e9f5b76f1a7d0a90dd31627030ba31e030f73d946daadb
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Nydahl, AnnaWallin, MarcusTranvik, LarsHiller, CarolinAttermeyer, KatrinGarrison, Julie A.Chaguaceda, FernandoScharnweber, KristinWeyhenmeyer, Gesa A.

Search in DiVA

By author/editor
Nydahl, AnnaWallin, MarcusTranvik, LarsHiller, CarolinAttermeyer, KatrinGarrison, Julie A.Chaguaceda, FernandoScharnweber, KristinWeyhenmeyer, Gesa A.
By organisation
LimnologyLUVAL
In the same journal
Limnology and Oceanography
Oceanography, Hydrology and Water Resources

Search outside of DiVA

GoogleGoogle Scholar
Total: 172 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 222 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf