umu.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Karlsson, Jan
Alternative names
Publications (10 of 88) Show all publications
Bergström, A.-K., Karlsson, J., Karlsson, D. & Vrede, T. (2018). Contrasting plankton stoichiometry and nutrient regeneration in northern arctic and boreal lakes. Aquatic Sciences, 80(2), Article ID UNSP 24.
Open this publication in new window or tab >>Contrasting plankton stoichiometry and nutrient regeneration in northern arctic and boreal lakes
2018 (English)In: Aquatic Sciences, ISSN 1015-1621, E-ISSN 1420-9055, Vol. 80, no 2, article id UNSP 24Article in journal (Refereed) Published
Abstract [en]

Contrasting carbon: nitrogen: phosphorus (C: N: P) stoichiometry between phytoplankton and zooplankton affect consumer growth and phytoplankton nutrient limitation via nutrient recycling by zooplankton. However, no study has assessed how regional differences in terrestrial loadings of organic matter affect plankton N: P stoichiometry and recycling in systems with low N deposition and N-limited phytoplankton. We address this question by using data from 14 unproductive headwater arctic and boreal lakes. We found that boreal lakes had higher lake water-and seston C, N and P concentrations than arctic lakes, whereas seston C: N, C: P and N: P ratios did not differ among regions. Boreal zooplankton were also richer in N and P relative to C, with lower somatic N: P ratios, compared to arctic lakes. Consequently, the estimated N: P imbalances between seston and zooplankton were negative in arctic lakes, indicating zooplankton feeding on phytoplankton of suboptimal N content, resulting in low consumer driven N: P recycling (medians arctic sub-mid and high altitude lakes: 11 and 13). In boreal lakes, estimated N: P imbalance did not differ from zero, with a seston N: P stoichiometry matching the N: P requirements of zooplankton, which resulted in higher consumer driven N: P recycling (median 18). Our results imply that regional climate induced catchment differences, through enhanced terrestrial nutrient inputs, affect plankton stoichiometry by raising consumer N: P recycling ratio and changing zooplankton from being mainly N-(arctic) to NP co-limited (boreal). Browning of lakes, in regions with low N deposition, may therefore promote large-scale regional changes in plankton nutrient limitation with potential feedbacks on pelagic food webs.

Place, publisher, year, edition, pages
Springer, 2018
Keywords
Carbon, Nitrogen, Nutrient limitation, Phosphorus, Phytoplankton, Zooplankton
National Category
Oceanography, Hydrology and Water Resources Environmental Sciences Ecology
Identifiers
urn:nbn:se:umu:diva-147316 (URN)10.1007/s00027-018-0575-2 (DOI)000429435600001 ()
Available from: 2018-05-25 Created: 2018-05-25 Last updated: 2018-06-19Bibliographically approved
Pokrovsky, O. S., Karlsson, J. & Giesler, R. (2018). Freeze-thaw cycles of Arctic thaw ponds remove colloidal metals and generate low-molecular-weight organic matter. Biogeochemistry, 137(3), 321-336
Open this publication in new window or tab >>Freeze-thaw cycles of Arctic thaw ponds remove colloidal metals and generate low-molecular-weight organic matter
2018 (English)In: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 137, no 3, p. 321-336Article in journal (Refereed) Published
Abstract [en]

High-latitude boreal and arctic surface/inland waters contain sizeable reservoirs of dissolved organic matter (DOM) and trace elements (TE), which are subject to seasonal freezing. Specifically, shallow ponds and lakes in the permafrost zone often freeze solid, which can lead to transformations in the colloidal and dissolved fractions of DOM and TE. Here, we present results from experimental freeze-thaw cycles using iron (Fe)- and DOM-rich water from thaw ponds situated in Stordalen and Storflaket palsa mires in northern Sweden. After ten cycles of freezing, 85% of Fe and 25% of dissolved organic carbon (DOC) were removed from solution in circumneutral fen water (pH 6.9) but a much smaller removal of Fe and DOC (< 7%) was found in acidic bog water (pH 3.6). This removal pattern was consistent with initial supersaturation of fen water with respect to Fe hydroxide and a lack of supersaturation with any secondary mineral phase in the bog water. There was a nearly two- to threefold increase in the low-molecular-weight (LMW) fraction of organic carbon (OC) and several TEs caused by the repeated freeze-thaw cycles. Future increases in the freeze-thaw frequency of surface waters with climate warming may remove up to 25% of DOC in circumneutral organic-rich waters. Furthermore, an increase of LMW OC may result in enhanced carbon dioxide losses from aquatic ecosystems since this fraction is potentially more susceptible to biodegradation.

Keywords
Peat, Fen, Bog, Ultrafiltration, Metal, Carbon
National Category
Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-145600 (URN)10.1007/s10533-018-0421-6 (DOI)000425543200004 ()
Funder
Swedish Research Council, 2013-5001
Available from: 2018-03-22 Created: 2018-03-22 Last updated: 2018-06-09Bibliographically approved
Ala-aho, P., Soulsby, C., Pokrovsky, O. S., Kirpotin, S. N., Karlsson, J., Serikova, S., . . . Tetzlaff, D. (2018). Permafrost and lakes control river isotope composition across a boreal Arctic transect in the Western Siberian lowlands. Environmental Research Letters, 13(3), =20-=20, Article ID 034028.
Open this publication in new window or tab >>Permafrost and lakes control river isotope composition across a boreal Arctic transect in the Western Siberian lowlands
Show others...
2018 (English)In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 13, no 3, p. =20-=20, article id 034028Article in journal (Refereed) Published
Abstract [en]

The Western Siberian Lowlands (WSL) store large quantities of organic carbon that will be exposed and mobilized by the thawing of permafrost. The fate of mobilized carbon, however, is not well understood, partly because of inadequate knowledge of hydrological controls in the region which has a vast low-relief surface area, extensive lake and wetland coverage and gradually increasing permafrost influence. We used stable water isotopes to improve our understanding of dominant landscape controls on the hydrology of the WSL. We sampled rivers along a 1700 km South-North transect from permafrost-free to continuous permafrost repeatedly over three years, and derived isotope proxies for catchment hydrological responsiveness and connectivity. We found correlations between the isotope proxies and catchment characteristics, suggesting that lakes and wetlands are intimately connected to rivers, and that permafrost increases the responsiveness of the catchment to rainfall and snowmelt events, reducing catchment mean transit times. Our work provides rare isotope-based field evidence that permafrost and lakes/wetlands influence hydrological pathways across a wide range of spatial scales (10-105 km2) and permafrost coverage (0%-70%). This has important implications, because both permafrost extent and lake/wetland coverage are affected by permafrost thaw in the changing climate. Changes in these hydrological landscape controls are likely to alter carbon export and emission via inland waters, which may be of global significance.

Keywords
stable water isotopes, Western Siberia Lowlands, mean transit time, hydrological connectivity, permafrost
National Category
Oceanography, Hydrology and Water Resources
Identifiers
urn:nbn:se:umu:diva-146150 (URN)10.1088/1748-9326/aaa4fe (DOI)000426518100004 ()
Available from: 2018-05-03 Created: 2018-05-03 Last updated: 2018-06-09Bibliographically approved
Berggren, M., Klaus, M., Selvam, B. P., Ström, L., Laudon, H., Jansson, M. & Karlsson, J. (2018). Quality transformation of dissolved organic carbon during water transit through lakes: contrasting controls by photochemical and biological processes. Biogeosciences, 15(2), 457-470
Open this publication in new window or tab >>Quality transformation of dissolved organic carbon during water transit through lakes: contrasting controls by photochemical and biological processes
Show others...
2018 (English)In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 15, no 2, p. 457-470Article in journal (Refereed) Published
Abstract [en]

Dissolved organic carbon (DOC) may be removed, transformed, or added during water transit through lakes, resulting in changes in DOC composition and pigmentation (color). However, the process-based understanding of these changes is incomplete, especially for headwater lakes. We hypothesized that because heterotrophic bacteria preferentially consume noncolored DOC, while photochemical processing removes colored fractions, the overall changes in DOC color upon water passage through a lake depend on the relative importance of these two processes, accordingly. To test this hypothesis we combined laboratory experiments with field studies in nine boreal lakes, assessing both the relative importance of different DOC decay processes (biological or photochemical) and the loss of color during water transit time (WTT) through the lakes. We found that influence from photo-decay dominated changes in DOC quality in the epilimnia of relatively clear headwater lakes, resulting in systematic and selective net losses of colored DOC. However, in highly pigmented brown-water lakes (absorbance at 420 nm > 7 m(-1)) biological processes dominated, and there was no systematic relationship between color loss and WTT. Moreover, in situ data and dark experiments supported our hypothesis on the selective microbial removal of nonpigmented DOC, mainly of low molecular weight, leading to persistent water color in these highly colored lakes. Our study shows that brown headwater lakes may not conform to the commonly reported pattern of the selective removal of colored constituents in freshwaters, as DOC can show a sustained degree of pigmentation upon transit through these lakes.

Place, publisher, year, edition, pages
European Geosciences Union (EGU), 2018
National Category
Ecology Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-144829 (URN)10.5194/bg-15-457-2018 (DOI)000423346300001 ()
Available from: 2018-03-02 Created: 2018-03-02 Last updated: 2018-06-09Bibliographically approved
Ala-aho, P., Soulsby, C., Pokrovsky, O. S., Kirpotin, S. N., Karlsson, J., Serikova, S., . . . Tetzlaff, D. (2018). Using stable isotopes to assess surface water source dynamics and hydrological connectivity in a high-latitude wetland and permafrost influenced landscape. Journal of Hydrology, 556, 279-293
Open this publication in new window or tab >>Using stable isotopes to assess surface water source dynamics and hydrological connectivity in a high-latitude wetland and permafrost influenced landscape
Show others...
2018 (English)In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 556, p. 279-293Article in journal (Refereed) Published
Abstract [en]

Climate change is expected to alter hydrological and biogeochemical processes in high-latitude inland waters. A critical question for understanding contemporary and future responses to environmental change is how the spatio-temporal dynamics of runoff generation processes will be affected. We sampled stable water isotopes in soils, lakes and rivers on an unprecedented spatio-temporal scale along a 1700 km transect over three years in the Western Siberia Lowlands. Our findings suggest that snowmelt mixes with, and displaces, large volumes of water stored in the organic soils and lakes to generate runoff during the thaw season. Furthermore, we saw a persistent hydrological connection between water bodies and the landscape across permafrost regions. Our findings help to bridge the understanding between small and large scale hydrological studies in high-latitude systems. These isotope data provide a means to conceptualise hydrological connectivity in permafrost and wetland influenced regions, which is needed for an improved understanding of future biogeochemical changes.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
Stable water isotopes, Hydrological connectivity, Runoff generation, Snowmelt, Low-relief
National Category
Oceanography, Hydrology and Water Resources
Identifiers
urn:nbn:se:umu:diva-144970 (URN)10.1016/j.jhydrol.2017.11.024 (DOI)000423641300022 ()
Available from: 2018-02-21 Created: 2018-02-21 Last updated: 2018-06-09Bibliographically approved
Klaus, M., Bergström, A.-K., Jonsson, A., Deininger, A., Geibrink, E. & Karlsson, J. (2018). Weak response of greenhouse gas emissions to whole lake N enrichment. Limnology and Oceanography, 63, S340-S353
Open this publication in new window or tab >>Weak response of greenhouse gas emissions to whole lake N enrichment
Show others...
2018 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 63, p. S340-S353Article in journal (Refereed) Published
Abstract [en]

Global warming and land use scenarios suggest increased 21st century nitrogen (N) inputs to aquatic systems. Nitrogen affects in-lake processing and, potentially, atmospheric exchange of greenhouse gases, probably being most relevant in unproductive systems. Here, we test for the first time the effect of a whole-lake experimental increase (threefold) in external nitrate loads on the atmospheric exchange of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from N-limited unproductive boreal lakes. Nitrate enrichment effects were assessed within a paired Before/After-Control/Impact framework based on 2-hourly to biweekly surface-water sampling of dissolved gas concentrations, and monthly whole-lake inventory surveys, carried out over 4 yrs in six lakes. Nitrate enrichment did not affect gas exchange during summer stratification and whole-lake gas inventories during summer and winter stratification. This finding specifically emphasizes the modest role of internal carbon fixation for the CO2 dynamics of unproductive boreal lakes. A global synthesis of 52 published studies revealed a wide range of nutrient fertilization effects, both in systems similar to our experimental lakes, and other more productive systems. Effects depended mainly on the spatiotemporal scale of the study and became more pronounced when N enrichment was combined with phosphorous. Conclusively, although short-term and habitat-specific effects can occur, changes in N supply have only weak whole-ecosystem effects on greenhouse gas emissions from unproductive boreal lakes.

National Category
Physical Geography
Identifiers
urn:nbn:se:umu:diva-135002 (URN)10.1002/lno.10743 (DOI)000427077300023 ()
Note

Originally included in thesis in manuscript form

Available from: 2017-05-15 Created: 2017-05-15 Last updated: 2018-06-09Bibliographically approved
Hedström, P., Bystedt, D., Karlsson, J., Bokma, F. & Byström, P. (2017). Brownification increases winter mortality in fish. Oecologia, 183(2), 587-595
Open this publication in new window or tab >>Brownification increases winter mortality in fish
Show others...
2017 (English)In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 183, no 2, p. 587-595Article in journal (Refereed) Published
Abstract [en]

In northernclimateswinter is a bottleneck for many organisms. Low light and resource availability constrain individual foraging rates,potentially leading tostarvation and increasedmortality.Increasinginput of humic substances to aquatic ecosystems causesbrownification of water and hence a further decreaseof light availability,which may lead tofurther decreased foraging ratesand starvation mortality during winter.To test this hypothesis, we measured the effectsof experimentally increased humicwaterinput on consumption and survival of young-of-the-year (YOY) three-spined stickleback (Gasterosteus aculeatus) over winterin largeoutdoor enclosures. Population densitieswereestimated in autumn andthefollowing springand food availabilityand consumptionwere monitoredoverwinter. As hypothesized,mortality washigher underhumic(76%)as compared to ambientconditions (64%).Also, body condition and ingested prey biomass werelower under humic conditionseven thoughresource availability wasnotlower under humic conditions. Light conditions were significantly poorer under humic conditions. This suggeststhat increased mortality and decreased body condition and ingested prey biomasswasnot due to decreased resource availability but due todecreasedsearch efficiencyin this visual feeding consumer. Increased future brownification of aquatic systems may therefore negatively affect both recruitment and densities of fish.

Keywords
Brownification, winter mortality, light limitation, feeding efficiency, metabolism
National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-127940 (URN)10.1007/s00442-016-3779-y (DOI)000394254500023 ()27915414 (Scopus ID)
Funder
The Kempe FoundationsSwedish Research Council for Environment, Agricultural Sciences and Spatial Planning, 621-2011-3908Ecosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGE
Note

Originally published in manuscript form.

Available from: 2016-11-21 Created: 2016-11-21 Last updated: 2018-06-09Bibliographically approved
Gudasz, C., Ruppenthal, M., Kalbitz, K., Cerli, C., Fielder, S., Oelmann, Y., . . . Karlsson, J. (2017). Contributions of terrestrial organic carbon to northern lake sediments. Limnology and Oceanography Letters
Open this publication in new window or tab >>Contributions of terrestrial organic carbon to northern lake sediments
Show others...
2017 (English)In: Limnology and Oceanography Letters, ISSN 2378-2242Article in journal (Refereed) Epub ahead of print
Abstract [en]

Sediments of northern lakes sequester large amounts of organic carbon (OC), but direct evidence of the relative importance of their sources is lacking. We used stable isotope ratios of nonexchangeable hydrogen (δ2Hn) in topsoil, algae, and surface sediments in order to measure the relative contribution of terrestrial OC in surface sediments of 14 mountainous arctic and lowland boreal lakes in Sweden. The terrestrial contribution to the sediment OC pool was on average 66% (range 46–80) and similar between arctic and boreal lakes. Proxies for the supply of terrestrial and algal OC explained trends in the relative contribution of terrestrial OC across lakes. However, the data suggest divergent predominant sources for terrestrial OC of sediments in Swedish lakes, with dissolved matter dominating in lowland boreal lakes and particulate OC in mountainous arctic lakes.

National Category
Earth and Related Environmental Sciences
Identifiers
urn:nbn:se:umu:diva-142341 (URN)10.1002/lol2.10051 (DOI)
Available from: 2017-11-28 Created: 2017-11-28 Last updated: 2018-06-09
Rocher-Ros, G., Giesler, R., Lundin, E., Salimi, S., Jonsson, A. & Karlsson, J. (2017). Large lakes dominate CO2 evasion from lakes in an arctic catchment. Geophysical Research Letters, 44(24), 12254-12261
Open this publication in new window or tab >>Large lakes dominate CO2 evasion from lakes in an arctic catchment
Show others...
2017 (English)In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 44, no 24, p. 12254-12261Article in journal (Refereed) Published
Abstract [en]

CO2 evasion from freshwater lakes is an important component of the carbon cycle. However, the relative contribution from different lake sizes may vary, since several parameters underlying CO2 flux are size dependent. Here we estimated the annual lake CO2 evasion from a catchment in northern Sweden encompassing about 30,000 differently sized lakes. We show that areal CO2 fluxes decreased rapidly with lake size, but this was counteracted by the greater overall coverage of larger lakes. As a result, total efflux increased with lake size and the single largest lake in the catchment dominated the CO2 evasion (53% of all CO2 evaded). By contrast, the contribution from the smallest ponds (about 27,000) was minor (<6%). Our results emphasize the importance of accounting for both CO2 flux rates and areal contribution of various sized lakes in assessments of CO2 evasion at the landscape scale.

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2017
National Category
Geophysics Oceanography, Hydrology and Water Resources
Identifiers
urn:nbn:se:umu:diva-144858 (URN)10.1002/2017GL076146 (DOI)000422954700049 ()
Available from: 2018-02-22 Created: 2018-02-22 Last updated: 2018-06-09Bibliographically approved
Deininger, A., Faithfull, C. L., Karlsson, J., Klaus, M. & Bergström, A.-K. (2017). Pelagic food web response to whole lake N fertilization. Limnology and Oceanography, 62(4), 1498-1511
Open this publication in new window or tab >>Pelagic food web response to whole lake N fertilization
Show others...
2017 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 62, no 4, p. 1498-1511Article in journal (Refereed) Published
Abstract [en]

Anthropogenic activities are increasing inorganic nitrogen (N) loadings to unproductive boreal lakes. In many of these lakes phytoplankton are N limited, consequently N fertilization may affect ecosystem productivity and consumer resource use. Here, we conducted whole lake inorganic N fertilization experiments with six small N limited unproductive boreal lakes (three control and three N enriched) in an area receiving low N deposition with one reference and two impact years. Our aim was to assess the effects of N fertilization on pelagic biomass production and consumer resource use. We found that phytoplankton primary production (PP) and biomass, and the PP: bacterioplankton production ratio increased after fertilization. As expected, the relative contribution of phytoplankton derived resources (autochthony) that supported the crustacean zooplankton community increased. Yet, the response in the consumer community was modest with autochthony only increasing in one of the three major zooplankton groups and with no effect on zooplankton biomass. In conclusion, our findings imply that newly available phytoplankton energy derived from N fertilization was not efficiently transferred up to zooplankton, indicating a mismatch between producer energy supply and consumer energy use with potential accumulation of phytoplankton biomass as the result.

Keywords
autochthony, basal production, boreal, dissolved organic carbon, limitation, nitrate, phytoplankton, zooplankton
National Category
Ecology Environmental Sciences
Research subject
Limnology
Identifiers
urn:nbn:se:umu:diva-130332 (URN)10.1002/lno.10513 (DOI)000404993100013 ()
Funder
Swedish Research Council, 621-2010-4675
Available from: 2017-01-17 Created: 2017-01-17 Last updated: 2018-06-09Bibliographically approved
Organisations

Search in DiVA

Show all publications