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Brunberg, Anna-Kristina
Alternative names
Publications (10 of 16) Show all publications
Vrede, T., Ballantyne, A. P., Mille-Lindblom, C., Algesten, G., Gudasz, C., Lindahl, S. & Brunberg, A.-K. (2009). Effects of N:P loading ratios on phytoplankton community composition, primary production, and N fixation in a eutrophic lake. Freshwater Biology, 54(2), 331-344
Open this publication in new window or tab >>Effects of N:P loading ratios on phytoplankton community composition, primary production, and N fixation in a eutrophic lake
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2009 (English)In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 54, no 2, p. 331-344Article in journal (Refereed) Published
Abstract [en]

1. The aim of this study was to assess the effects of different nitrogen (N) to  phosphorus (P) loading ratios on phytoplankton community composition and primary production in a naturally eutrophic lake. Furthermore, the sources of N fuelling primary production were estimated using 15N stable isotope tracers.

2. A mesocosm experiment was performed with the same amount of P added to all mesocosms (similar to internal loading rates) but with a range of N additions (0–86 μm N), resulting in a gradient of N : P supply ratios.

3. Low N : P supply ratios resulted in a significant shift in the phytoplankton assemblage to a community dominated by N-fixing cyanobacteria and a supply of atmospheric N2 estimated to be up to 60% of total supply.

4. The N : P loading ratio had no significant effect on primary production, total nitrogen (TN) concentration or particulate N concentration.

5. Our results imply that a reduced N : P ratio of the nutrient load does not necessarily result in a lower TN concentration and downstream N export due to compensation by N-fixing cyanobacteria.

 

 

Keywords
15N stable isotopes, eutrophication, nitrogen, phosphorus, stoichiometry
National Category
Biological Sciences
Identifiers
urn:nbn:se:uu:diva-111716 (URN)10.1111/j.1365-2427.2008.02118.x (DOI)000262470300009 ()
Available from: 2009-12-21 Created: 2009-12-21 Last updated: 2022-01-28Bibliographically approved
Sobek, S., Söderbäck, B., Karlsson, S., Andersson, E. & Brunberg, A.-K. (2006). A carbon budget of a small humic lake: An example of the importance of lakes for organic matter cycling in boreal catchments. Ambio, 35(8), 469-475
Open this publication in new window or tab >>A carbon budget of a small humic lake: An example of the importance of lakes for organic matter cycling in boreal catchments
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2006 (English)In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 35, no 8, p. 469-475Article in journal (Refereed) Published
Abstract [en]

Lakes play an important role in the cycling of organic matter in the boreal landscape, due to the frequently high extent of bacterial respiration and the efficient burial of organic carbon in sediments. Based on a mass balance approach, we calculated a carbon budget for a small humic Swedish lake in the vicinity of a potential final repository for radioactive waste in Sweden, in order to assess its potential impact on the environmental fate of radionuclides associated with organic matter. We found that the lake is a net heterotrophic ecosystem, subsidized by organic carbon inputs from the catchment and from emergent macrophyte production. The largest sink of organic carbon is respiration by aquatic bacteria and subsequent emission of carbon dioxide to the atmosphere. Although the annual burial of organic carbon in the sediment is a comparatively small sink, it results in the build-up of the largest carbon pool in the lake. Hence, lakes may simultaneously disperse and accumulate organic-associated radionuclides leaking from a final repository.

National Category
Biological Sciences
Identifiers
urn:nbn:se:uu:diva-23080 (URN)10.1579/0044-7447(2006)35[469:ACBOAS]2.0.CO;2 (DOI)000243606600006 ()17334054 (PubMedID)
Available from: 2008-01-28 Created: 2008-01-28 Last updated: 2018-06-05
Andersson, E. & Brunberg, A.-K. (2006). Inorganic nutrient acquisition in a shallow clearwater lake: dominance of benthic microbiota. Aquatic Sciences, 68(2), 172-180
Open this publication in new window or tab >>Inorganic nutrient acquisition in a shallow clearwater lake: dominance of benthic microbiota
2006 (English)In: Aquatic Sciences, ISSN 1015-1621, E-ISSN 1420-9055, Vol. 68, no 2, p. 172-180Article in journal (Refereed) Published
Abstract [en]

This mesocosm study from the oligotrophic Lake Eckarfjärden in Sweden shows, in contrast to many previous studies, that benthic microbiota dominated production following elevated nutrient concentrations in the water. Increased nutrient concentrations favoured microphytobenthos, whereas phytoplankton biomass remained roughly the same. Microphytobenthos biomass and production were clearly stimulated by nitrogen addition, while phytoplankton showed signs of phosphorus limitation. There were tight interactions between pelagic and benthic habitats and between organisms, and pelagic as well as benthic heterotrophic bacteria were disfavoured when microphytobenthos had access to nitrogen.

We conclude that increased nutrient concentrations in the water column may trigger immediate responses in both habitats, altering the tight interactions between microbiota, but not necessarily resulting in a shift towards pelagic production.

National Category
Natural Sciences
Identifiers
urn:nbn:se:uu:diva-93056 (URN)10.1007/s00027-006-0805-x (DOI)
Available from: 2005-05-11 Created: 2005-05-11 Last updated: 2018-06-05Bibliographically approved
Andersson, E. & Brunberg, A.-K. (2006). Net autotrophy in an oligotrophic lake rich in dissolved organic carbon and with high benthic primary production. Aquatic Microbial Ecology, 43(1), 1-10
Open this publication in new window or tab >>Net autotrophy in an oligotrophic lake rich in dissolved organic carbon and with high benthic primary production
2006 (English)In: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 43, no 1, p. 1-10Article in journal (Refereed) Published
Abstract [en]

Biomass and production of microbiota—primary producers as well as heterotrophic bacteria—were studied both in the pelagial and in the benthic habitat over 2 yr in the shallow oligotrophic Lake Eckarfjärden, Sweden. Both biomass and production of microbiota were concentrated in the benthic habitat. Despite a high dissolved organic carbon (DOC) concentration of about 25 mg C l–1 in the water, the total bacterial production was lower than the total primary production. Moreover, measurements of DOC concentrations in the in- and outflow, and CO2-saturation measurements, indicate that the system is net autotrophic. Generally, low-productive systems (<100 µg C l–1 d–1) tend to be net heterotrophic. In contrast, we found a low-productive (55 µg C l–1 d–1) but net autotrophic system, the conditions of which were largely influenced by benthic production. Many lakes in the world are shallow and may provide substantial benthic areas suitable for primary production. Hence, it is important to include this habitat when evaluating whether lakes are autotrophic or heterotrophic systems.

National Category
Natural Sciences
Identifiers
urn:nbn:se:uu:diva-93055 (URN)10.3354/ame043001 (DOI)
Available from: 2005-05-11 Created: 2005-05-11 Last updated: 2018-06-05Bibliographically approved
Brydsten, L., Carlsson, T., Brunberg, A.-K. & Blomqvist, P. (2004). A method for determination of morphometry, sediment distribution, and habitat diversity of lake basins and its application to three lakes in Uppland.. Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden.
Open this publication in new window or tab >>A method for determination of morphometry, sediment distribution, and habitat diversity of lake basins and its application to three lakes in Uppland.
2004 (English)Report (Other academic)
Place, publisher, year, edition, pages
Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden., 2004
Identifiers
urn:nbn:se:uu:diva-79182 (URN)
Available from: 2006-04-05 Created: 2006-04-05 Last updated: 2018-06-05
Brunberg, A.-K., Carlsson, T., Brydsten, L. & Strömgren, M. (2004). Forsmark site investigation. Identification of catchments, lake-related drainage parameters and lake habitats.. Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden.
Open this publication in new window or tab >>Forsmark site investigation. Identification of catchments, lake-related drainage parameters and lake habitats.
2004 (English)Report (Other academic)
Place, publisher, year, edition, pages
Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden., 2004
Identifiers
urn:nbn:se:uu:diva-79183 (URN)
Available from: 2006-04-05 Created: 2006-04-05 Last updated: 2018-06-05
Brunberg, A.-K., Carlsson, T., Brydsten, L. & Strömgren, M. (2004). Oskarshamn site investigation. Identification of catchments, lake-related drainage parameters and lake habitats.. Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden.
Open this publication in new window or tab >>Oskarshamn site investigation. Identification of catchments, lake-related drainage parameters and lake habitats.
2004 (English)Report (Other academic)
Place, publisher, year, edition, pages
Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden., 2004
Identifiers
urn:nbn:se:uu:diva-79186 (URN)
Available from: 2006-04-05 Created: 2006-04-05 Last updated: 2018-06-05
Karlsson-Elfgren, I. & Brunberg, A.-K. (2004). The Importance of Shallow Sediments in the Recruitment of Anabaena and Aphanizomenon (Cyanophyceae). Journal of Phycology, 40(5), 831-836
Open this publication in new window or tab >>The Importance of Shallow Sediments in the Recruitment of Anabaena and Aphanizomenon (Cyanophyceae)
2004 (English)In: Journal of Phycology, ISSN 0022-3646, E-ISSN 1529-8817, Vol. 40, no 5, p. 831-836Article in journal (Refereed) Published
Abstract [en]

Recruitment of Anabaena and Aphanizomenon from the sediments to the water column was investigated in shallow (1-2 m) and deep (6-7 m) areas of Lake Limmaren, central Sweden. Recruitment traps attached to the bottom were sampled weekly throughout the summer season (June through September). A comparison between the two sites shows that the largest part of the recruited cells originated from the shallow site, although recruitment occurred at all depths in the lake. There were also differences between the species, regarding the site as well as the timing of the recruitment. The contribution of the inoculum to the pelagic population was calculated to vary between 0.003% and 0.05% for the different species. From these results we conclude that shallow sediments are more important than deep ones for the recruitment and that the inoculum in Lake Limmaren is small but may still be an important factor in the population dynamics.

National Category
Ecology
Identifiers
urn:nbn:se:uu:diva-90428 (URN)10.1111/j.1529-8817.2004.04070.x (DOI)
Available from: 2003-05-14 Created: 2003-05-14 Last updated: 2018-06-05Bibliographically approved
Brunberg, A.-K. & Blomqvist, P. (2003). Ontogeny of lake ecosystems in the Forsmark area - chemical analysis of deep sediment cores. Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden.
Open this publication in new window or tab >>Ontogeny of lake ecosystems in the Forsmark area - chemical analysis of deep sediment cores
2003 (English)Report (Other academic)
Place, publisher, year, edition, pages
Swedish Nuclear Fuel and Waste Management Co., Stockholm, Sweden., 2003
Identifiers
urn:nbn:se:uu:diva-47535 (URN)
Available from: 2006-04-05 Created: 2006-04-05 Last updated: 2018-06-05
Brunberg, A.-K. & Blomqvist, P. (2003). Recruitment of Microcystis (Cyanophyceae) from lake sediments: the importance of littoral inocula. J. Phycol., 39, 58-63.
Open this publication in new window or tab >>Recruitment of Microcystis (Cyanophyceae) from lake sediments: the importance of littoral inocula
2003 (English)In: J. Phycol., Vol. 39, p. 58-63.Article in journal (Refereed) Published
Identifiers
urn:nbn:se:uu:diva-47534 (URN)
Available from: 2006-04-05 Created: 2006-04-05 Last updated: 2018-06-05
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