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Jonsson, Anders
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Publications (10 of 34) Show all publications
Karlsson, J., Berggren, M., Ask, J., Byström, P., Jonsson, A., Laudon, H. & Jansson, M. (2014). Response to Comment: Terrestrial support of pelagic consumers in unproductive lakes- Uncertainty and potential in assessments using stable isotopes. Limnology and Oceanography, 59(5), 1800-1803.
Open this publication in new window or tab >>Response to Comment: Terrestrial support of pelagic consumers in unproductive lakes- Uncertainty and potential in assessments using stable isotopes
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2014 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 59, no 5, 1800-1803 p.Article in journal, Editorial material (Refereed) Published
National Category
Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-98410 (URN)10.4319/lo.2014.59.5.1800 (DOI)000345462100027 ()
Available from: 2015-01-22 Created: 2015-01-22 Last updated: 2017-08-31Bibliographically approved
Jansson, M., Berggren, M., Laudon, H. & Jonsson, A. (2012). Bioavailable phosphorus in humic headwater streams in boreal Sweden. Limnology and Oceanography, 57(4), 1161-1170.
Open this publication in new window or tab >>Bioavailable phosphorus in humic headwater streams in boreal Sweden
2012 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 57, no 4, 1161-1170 p.Article in journal (Refereed) Published
Abstract [en]

Bioavailable phosphorus (BAP) concentrations were determined nine times between April and October 2010 in two humic boreal headwater streams draining forest-and mire-dominated catchments. BAP was analyzed in a bioassay in which natural P-limited bacterioplankton grew with natural P as the sole P source. In both streams, approximately 90% of the BAP occurred as dissolved species (passing a 0.2-mu m filter), consisting partly of low-molecular-weight forms (passing a filter with nominal cutoff at 1 kDa) and partly of high-molecular-weight forms (passing a 0.2-mu m filter but not a 1-kDa filter). Concentrations of total dissolved BAP varied between 1 mu g L-1 and 14 mu g L-1, with the highest values in the middle of the summer. Compared to the forest stream, BAP concentrations were generally higher in the mire stream, where it occasionally amounted to nearly 50% of total P. Molybdate reactive phosphorus overestimated BAP considerably. Most of the BAP was in forms other than free orthophosphate. Temporal BAP variations showed no relationships with dissolved organic carbon (C) or iron but were positively related to air temperature and negatively related to the absorbance ratio (a254 : a365) of organic compounds in the water, indicating connections between terrestrial export of BAP and temperature-dependent terrestrial C metabolism. Concentrations of BAP can relieve stream bacteria from P limitation, and a significant share of BAP exported to streams can reach and be used in downstream lakes.

National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-59734 (URN)10.4319/lo.2012.57.4.1161 (DOI)000307269300021 ()
Available from: 2012-10-18 Created: 2012-09-25 Last updated: 2017-12-07Bibliographically approved
Jansson, M., Karlsson, J. & Jonsson, A. (2012). Carbon dioxide supersaturation promotes primary production in lakes [Letter to the editor]. Ecology Letters, 15(6), 527-532.
Open this publication in new window or tab >>Carbon dioxide supersaturation promotes primary production in lakes
2012 (English)In: Ecology Letters, ISSN 1461-023X, E-ISSN 1461-0248, Vol. 15, no 6, 527-532 p.Article in journal, Letter (Refereed) Published
Abstract [en]

Ecology Letters (2012) Abstract A majority of the worlds lakes are supersaturated with respect to carbon dioxide (CO2). By experimental manipulation of the CO2 concentration in supersaturated boreal lakes, we demonstrate that phytoplankton primary production was up to 10 times higher in supersaturated lake water in comparison with water with CO2 at equilibrium concentrations and that CO2, together with nutrients, explained most of the variation in pelagic primary production and phytoplankton biomass over a wide variety of unproductive lakes. These results suggest that phytoplankton can be co-limited by CO2 and nutrients in unproductive lakes. As import of terrestrial organic carbon and its subsequent microbial mineralisation in lakes is a driving force of CO2-supersaturation our results suggest that lake productivity and carbon cycling may respond to variations in terrestrial organic carbon export, (e.g. caused by land use or climate change) in ways not described before.

Keyword
CO2-supersaturation, lake ecosystems, primary production
National Category
Earth and Related Environmental Sciences Ecology
Identifiers
urn:nbn:se:umu:diva-56202 (URN)10.1111/j.1461-0248.2012.01762.x (DOI)000303666200003 ()
Available from: 2012-06-12 Created: 2012-06-12 Last updated: 2017-12-07Bibliographically approved
Karlsson, J., Berggren, M., Ask, J., Byström, P., Jonsson, A., Laudon, H. & Jansson, M. (2012). Terrestrial organic matter support of lake food webs: Evidence from lake metabolism and stable hydrogen isotopes of consumers. Limnology and Oceanography, 57(4), 1042-1048.
Open this publication in new window or tab >>Terrestrial organic matter support of lake food webs: Evidence from lake metabolism and stable hydrogen isotopes of consumers
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2012 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 57, no 4, 1042-1048 p.Article in journal (Refereed) Published
Abstract [en]

We quantified the utilization of terrestrial organic matter (OM) in the food web of a humic lake by analyzing the metabolism and the consumers' stable isotopic (C, H, N) composition in benthic and pelagic habitats. Terrestrial OM inputs (3 g C m(-2) d(-1)) to the lake greatly exceeded autochthonous OM production (3 mg C m(-2) d(-1)) in the lake. Heterotrophic bacterial growth (19 mg C m(-2) d(-1)) and community respiration (115 mg C m(-2) d(-1)) were high relative to algal photosynthesis and were predominantly (> 85%) supported by terrestrial OM in both habitats. Consequently, terrestrial OM fueled most (85%) of the total production at the base of the lake's food web (i.e., the sum of primary and bacterial production). Despite the uncertainties of quantitatively estimating resource use based on stable isotopes, terrestrial OM clearly also supported around half the zooplankton (47%), macrozoobenthos (63%), and fish (57%) biomass. These results indicate that, although rates of terrestrial OM inputs were around three orders of magnitude greater than that of autochthonous OM production, the use of the two resources by higher trophic levels was roughly equal. The disproportionally low reliance on terrestrial OM at higher trophic levels, compared with its high rates of input and high support of basic biomass production in the lake, suggests that autochthonous resources could not be completely replaced by terrestrial resources and indicates an upper limit to terrestrial support of lake food webs.

National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-59733 (URN)10.4319/lo.2012.57.4.1042 (DOI)000307269300011 ()
Available from: 2012-10-18 Created: 2012-09-25 Last updated: 2017-10-23Bibliographically approved
Jansson, M., Jonsson, A., Andersson, A. & Karlsson, J. (2010). Biomass and structure of planktonic communities along an air temperature gradient in subarctic Sweden. Freshwater Biology, 55(3), 691-700.
Open this publication in new window or tab >>Biomass and structure of planktonic communities along an air temperature gradient in subarctic Sweden
2010 (English)In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 55, no 3, 691-700 p.Article in journal (Refereed) Published
Abstract [en]

1. Air temperature will probably have pronounced effects on the composition of plankton communities in northern lake ecosystems, either via indirect effects on the export of essential elements from catchments or through direct effects of water temperature and the ice-free period on the behaviour of planktonic organisms.

2. We assessed the role of temperature by comparing planktonic communities in 15 lakes along a 6 °C air temperature gradient in subarctic Sweden.

3. We found that the biomass of phytoplankton, bacterioplankton and the total planktonic biomass were positively related to air temperature, probably as a result of climatic controls on the export of nitrogen from the catchment (which affects phytoplankton biomass) and dissolved organic carbon (affecting bacterioplankton biomass).

4. The structure of the zooplankton community, and top down effects on phytoplankton, were apparently not related to temperature but mainly to trophic interactions ultimately dependent on the presence of fish in the lakes.

5. Our results suggest that air temperature regimes and long-term warming can have strong effects on the planktonic biomass in high latitude lakes. Effects of temperature on the structure of the planktonic community might be less evident unless warming permits the invasion of fish into previous fishless lakes.

Keyword
ecosystem, fish, lakes, phytoplankton, zooplankton
National Category
Biological Sciences
Identifiers
urn:nbn:se:umu:diva-31935 (URN)10.1111/j.1365-2427.2009.02310.x (DOI)000274814100015 ()
Available from: 2010-02-24 Created: 2010-02-24 Last updated: 2017-10-24Bibliographically approved
MacIntyre, S., Jonsson, A., Jansson, M., Åberg, J., Turney, D. E. & Miller, S. D. (2010). Buoyancy flux, turbulence, and the gas transfer coefficient in a stratified lake. Geophysical Research Letters, 37(L24604).
Open this publication in new window or tab >>Buoyancy flux, turbulence, and the gas transfer coefficient in a stratified lake
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2010 (English)In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 37, no L24604Article in journal (Refereed) Published
Abstract [en]

Gas fluxes from lakes and other stratified water bodies, computed using conservative values of the gas transfer coefficient k600, have been shown to be a significant component of the carbon cycle. We present a mechanistic analysis of the dominant physical processes modifying k600 in a stratified lake and resulting new models of k600 whose use will enable improved computation of carbon fluxes. Using eddy covariance results, we demonstrate that i) higher values of k600 occur during low to moderate winds with surface cooling than with surface heating; ii) under overnight low wind conditions k600 depends on buoyancy flux β rather than wind speed; iii) the meteorological conditions at the time of measurement and the inertia within the lake determine k600; and iv) eddy covariance estimates of k600 compare well with predictions of k600 using a surface renewal model based on wind speed and β.

Identifiers
urn:nbn:se:umu:diva-38928 (URN)10.1029/2010GL044164 (DOI)000285638900001 ()
Available from: 2011-01-11 Created: 2011-01-11 Last updated: 2017-12-11Bibliographically approved
Åberg, J., Jansson, M. & Jonsson, A. (2010). Importance of water temperature and thermal stratification dynamics for temporal variation of surface water CO2 in a boreal lake. Journal of Geophysical Research, 115(G02024), 10PP.
Open this publication in new window or tab >>Importance of water temperature and thermal stratification dynamics for temporal variation of surface water CO2 in a boreal lake
2010 (English)In: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 115, no G02024, 10PP- p.Article in journal (Refereed) Published
Abstract [en]

Variation of the surface water CO2 concentration is likely to be the result of biological activity and physical processes as water mixing and gas exchange with the atmosphere. Here we have studied the variations in surface water CO2 during the ice-free period in the humic Lake Merasjärvi in northern Sweden. Meteorological, hydrological and limnological data were collected using data logging equipment permitting high time-resolution. The surface water of the lake was supersaturated with respect to CO2 throughout the study period. There were, however, considerable diurnal and longer-term temporal variations of the surface water CO2 concentrations. Partial least squares (PLS) models were used to link the logged CO2 data to the multivariate dataset. On the longer-term time scale (analyzed with 24h means of the logged data) high concentrations of surface water CO2 were best related to the depth and temperature of the upper warmer layer (epilimnion), and to erosion of the underlying colder layer (hypolimnion). The diurnal variation (analyzed with 30 minute means of the logged data) was best related to the thermal dynamics within the epilimnion, which regulated the surface water access to CO2 stores within this layer. Variables related to CO2 emission and photosynthesis (wind and PAR), showed only weak correlations to variations of the surface water CO2 concentration. Accordingly, the CO2 flux, measured with the eddy-covariance technique, was not correlated to the surface water CO2 concentration.

Keyword
lake, carbon dioxide, PLS, thermal stratification, boreal
National Category
Earth and Related Environmental Sciences
Research subject
Physical Geography
Identifiers
urn:nbn:se:umu:diva-26965 (URN)10.1029/2009JG001085 (DOI)000279310300001 ()
Available from: 2009-11-04 Created: 2009-11-04 Last updated: 2017-12-12Bibliographically approved
Berggren, M., Ström, L., Laudon, H., Karlsson, J., Jonsson, A., Giesler, R., . . . Jansson, M. (2010). Lake secondary production fueled by rapid transfer of low molecular weight organic carbon from terrestrial sources to aquatic consumers. Ecology Letters, 13(7), 870-880.
Open this publication in new window or tab >>Lake secondary production fueled by rapid transfer of low molecular weight organic carbon from terrestrial sources to aquatic consumers
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2010 (English)In: Ecology Letters, ISSN 1461-023X, E-ISSN 1461-0248, Vol. 13, no 7, 870-880 p.Article in journal (Refereed) Published
Abstract [en]

Ecology Letters (2010) Abstract Carbon of terrestrial origin often makes up a significant share of consumer biomass in unproductive lake ecosystems. However, the mechanisms for terrestrial support of lake secondary production are largely unclear. By using a modelling approach, we show that terrestrial export of dissolved labile low molecular weight carbon (LMWC) compounds supported 80% (34-95%), 54% (19-90%) and 23% (7-45%) of the secondary production by bacteria, protozoa and metazoa, respectively, in a 7-km(2) boreal lake (conservative to liberal estimates in brackets). Bacterial growth on LMWC was of similar magnitude as that of primary production (PP), and grazing on bacteria effectively channelled the LMWC carbon to higher trophic levels. We suggest that rapid turnover of forest LMWC pools enables continuous export of fresh photosynthates and other labile metabolites to aquatic systems, and that substantial transfer of LMWC from terrestrial sources to lake consumers can occur within a few days. Sequestration of LMWC of terrestrial origin, thus, helps explain high shares of terrestrial carbon in lake organisms and implies that lake food webs can be closely dependent on recent terrestrial PP.

Keyword
Allochthony, lake secondary production, low molecular weight organic carbon
Identifiers
urn:nbn:se:umu:diva-34753 (URN)10.1111/j.1461-0248.2010.01483.x (DOI)000278798100010 ()20482576 (PubMedID)
Available from: 2010-06-16 Created: 2010-06-16 Last updated: 2017-12-12Bibliographically approved
Berggren, M., Laudon, H., Jonsson, A. & Jansson, M. (2010). Nutrient constraints on metabolism affect the temperature regulation of aquatic bacterial growth efficiency. Microbial Ecology, 60(4), 894-902.
Open this publication in new window or tab >>Nutrient constraints on metabolism affect the temperature regulation of aquatic bacterial growth efficiency
2010 (English)In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 60, no 4, 894-902 p.Article in journal (Refereed) Published
Abstract [en]

Inorganic nutrient availability and temperature are recognized as major regulators of organic carbon processing by aquatic bacteria, but little is known about how these two factors interact to control bacterial metabolic processes. We manipulated the temperature of boreal humic stream water samples within 0–25°C and measured bacterial production (BP) and respiration (BR) with and without inorganic nitrogen + phosphorus addition. Both BP and BR increased exponentially with temperature in all experiments, with Q 10 values varying between 1.2 and 2.4. The bacterial growth efficiency (BGE) showed strong negative relationships with temperature in nutrient-enriched samples and in natural stream water where community-level BP and BR were not limited by nutrients. However, there were no relationships between BGE and temperature in samples where BP and BR were significantly constrained by the inorganic nutrient availability. The results suggest that metabolic responses of aquatic bacterial communities to temperature variations can be strongly dependent on whether the bacterial metabolism is limited by inorganic nutrients or not. Such responses can have consequences for both the carbon flux through aquatic food webs and for the flux of CO2 from aquatic systems to the atmosphere.

Place, publisher, year, edition, pages
Springer, 2010
Identifiers
urn:nbn:se:umu:diva-37456 (URN)10.1007/s00248-010-9751-1 (DOI)000284255700019 ()
Available from: 2010-11-03 Created: 2010-11-03 Last updated: 2017-12-12Bibliographically approved
Jonsson, A., Åberg, J., Lindroth, A. & Jansson, M. (2008). Gas transfer rate and CO2 flux between an unproductive lake and the atmosphere in northern Sweden. Journal of Geophysical Research - Biogeosciences, 113, Art.no. G04006.
Open this publication in new window or tab >>Gas transfer rate and CO2 flux between an unproductive lake and the atmosphere in northern Sweden
2008 (English)In: Journal of Geophysical Research - Biogeosciences, Vol. 113, Art.no. G04006- p.Article in journal (Refereed) Published
Abstract [en]

Measurements of the gas transfer rate of CO2 between lake water and the atmosphere present a critical problem for the understanding of lake ecosystem carbon balances and landscape carbon budgets. We present calculations of the gas transfer rate of CO2 from direct measurements of the CO2 flux using an eddy covariance system and concurrent measurements of the concentration of CO2 in the surface water in a lake in boreal zone of northern Sweden. The measured gas transfer rate was different, and in general larger than, rates obtained with the most commonly used models for prediction of the gas transfer rate in lakes. The normalized gas transfer rate (k600EC) was well predicted from the wind speed at 10 m height if data were bin classed into wind classes of 1 m/s for winds above 1 m/s. Unbinned data were also correlated to wind speed but also to water temperature, water temperature/air temperature ratio and to incoming photosynthetic active radiation (PAR). These relationships could reflect effects of both physico-chemical reactions and biological activity.

Identifiers
urn:nbn:se:umu:diva-11368 (URN)10.1029/2008JG000688 (DOI)
Available from: 2008-12-16 Created: 2008-12-16 Last updated: 2009-11-11Bibliographically approved
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