Kristina Sundbäck, Professor

Benthic ecology, microbenthos, microbial ecology

My research deals with the benthic ecology of shallow-water, illuminated sediments, particularly the role of microbenthic communities (microalgae, bacteria and microscopic fauna) in the carbon and nutrient cycling. The response  and recovery of these shallow-water ecosystems when exposed to anthropogenic impacts, such as changed nutrient load, raised temperature due to climate change, physical disturbance, and toxicants, alone or in combination, are assessed.

Contact

Email: kristina.sundback@bioenv.gu.se
Tel: 031-786 2703
Visiting address: Department of Biological and Environmental Sciences, Carl Skottsbergs gata 22B, Gothenburg

Some current and recent projects:

Sensitivity, resilience and biodiversity of marine shallow-water sediment systems

Within this project, funded by FORMAS, we have focused on the capacity of shallow-water sediments to recover after human-induced environmental perturbations, such as oxygen deficiency and physical disturbance. The emphasis has been on the resilience and the role of microbially mediated key ecological functions and characters (primary production, trophic status, nutrient cycling, nitrogen retention and  removal, as well as the biodiversity of the benthic communities).  This experimental work, in which natural intact sediments were manipulated in outdoor flow-through mesocosms,  has resulted in a doctoral thesis: Fredrik Larson (2005) The role of marine microphytobenthos (MPB) with emphasis on resilience. In short, the results suggests that  MPB plays an important role in the recovery of the sediment system after temporary disturbance events, thereby contributing to the resilience of the shallow-water sediment system. This function appears to be related to the resistance of benthic diatoms to e.g. hypoxia and anoxia, and to their rapid re-oxygenation of the sediment surface. However, sedimentation appeared a more severe perturbation for microphytobenthos than single events of oxygen deficiency. The recovery time depended on the duration of the perturbation event.

Response of shallow-water illuminated sediments to multiple stressors, including the effect of raised temperature

This work, which started by the collaboration with  with NERI (DMU) in Denmark (Ingela Dahllöf, Dorthe Groth Petersen), focuses on the interactive effects of toxicants  and nutrient status.  The antifouling substance Cu-pyrithione and pyrine (PAH) are used as model toxicants. The approach is experimental, including both long-term outdoor experiments and mechanistic laboratory experiments. Both general ecosystem functions  and more specific processes, such as bacterially mediated N-turnover, are assessed. Resilience is assessed by studying the balance between key structural and functional properties related to productivity, trophic state and the capacity of the system to store, remove and recycle nutrients. Besides the function and diversity of  algae and fauna, special attention is paid to  bacterial processes driven  (bacterial production, nitrification, denitrification). The  presence and nature of indirect effects mediated by trophic links, such as grazing by  fauna, are studied. Hitherto gained results suggest that toxicant effects depend on nutrient status, so that nutrient-richer sediments show more and clearer response to toxicants than nutrient-poor sediment communities.  From 2007 and onwards, also temperature effects are considered. The main funding is currently from FORMAS. 

Role of shallow-water sediments as sinks and sources of nitrogen in the coastal zone

Within previous projects funded by EU and MISTRA, we started to study the role of shallow-water sediments as nitrogen (N) sinks, particularly the role of benthic primary producers for temporary N-retention. The balance between photoautotrophic and bacterial N-retaining/removing processes is assessed in relation to ecosystem type (primary producers, type of sediment, water depth and nutrient load). Measurements have been made on both the west and east coast of Sweden, i. a. along a 15 m depth gradient in a microtidal fjord (Gullmar Fjord).
    The importance of biogeochemical sediment processes for the growth of floating green-algal mats has been studied in a joint project together with  researchers at the Dept of Marine Ecology (Leif Pihl, Anna Engelsen) and  the Dept of Chemistry (Stefan Hulth).
    The role of dissolved organic nitrogen (DON) in the N-turnover and as a nitrogen source for benthic microalgae has also been studied. This work resulted in a doctoral thesis by Frank Linares (2004): Microphytobenthos and nitrogen fluxes, with special emphasis on dissolved organic nitrogen (DON), which showed that  dissolved free amino acids can constitute an important N source for benthic microalgae when DIN availability is limited. This work is continuing in co-operation with Edna Granéli´s group at the Universityof Kalmar.
    In co-operation with Dept of Chemistry at the University of Gothenburg (Stefan Hulth) and NERI in Denmark (Tage Dalsgaard), we have also studied the importance of alternative pathways of N-removal, such as anaerobic ammonium oxidation, in both shallow embayments  and deeper waters (funded by MISTRA).

In co-operation with the County Administration of Västra Götaland, management issues related to shallow coastal based are approached.

Other topics of interest:

Coupling between microbial biodiversity and functional redundancy in shallow-water sediment systems
Microbial food webs of sediments, role of grazing by macro- and meiofauna

Current PhD Candidates

Christian Alsterbeg, PhD candidate since 2008

Peer-reviewed articles  and book chapters (since 2000)

Engelsen A., Sundbäck K. Hulth S. (in press) Links between bottom-water anoxia, the polychaete Nereis diversicolor an the growth of green-alga. mats. Estaries and Coasts

Sundbäck, K., Alsterberg, C., Larson, F. (2010). Effects of multiple stressors on marine shallow-water sediment: response of microalgae and meiofauna to nutrient–toxicant exposure. J. Exp. Mar. Bio. Ecol. doi:10.1016/j.jembe.2010.03.007

Petersen D.G., Sundbäck K, Larson, F. Dahllöf I. (2009) Pyrene toxicity is affected by the nutrient status of a marine sediment community: Implications for risk asssesment. Aquat. Tox. 37-43

Engelsen, A., Hulth, S., Pihl. L., Sundbäck, K. (2008) Benthic trophic status and nutrient fluxes in shallow-water sediments. Estuar. Coast. Shelf Sci. 78:783-795

Larson F., Sundbäck, K. (2008) Role of microphytobenthos in recovery of functions in a shallow-water sediment system after hypoxic events. Mar.Ecol. Prog. Ser. 357: 1-16. Feature article

Alsterberg, C., Sundbäck, K., Larson, F. (2007) Direct and indirect effects of an antifouling biocide on benthic microalgae and meiofauna. J. Expt. Mar. Biol. Ecol. 351: 56-72

McGlathery, KJ, Sundbäck, K., Anderson, I (2007) Eutrophication in shallow coastal bays and lagoons: the role of plants in the coastal filter. Mar. Ecol. Prog. Ser. 348: 1-18. Feature article.

Larson, F., Petersen, D.G. Dahllöf, I., Sundbäck, K. (2007) Combined effects of an antifouling biocide and nutrient status on a shallow-water microbenthic community. Aquat. Microb. Ecol. 48: 277-294

Sundbäck, K., Petersen, D.G., Dahllöf, I., Larson, F. (2007) Combined nutrient – toxicant effects on a shallow-water sediment system: sensitivity and resilience of ecosystem functions Mar Ecol Prog Ser 330:13-30

Wulff, A., Mohlin, M., Sundbäck, K. (2007) Intraspecific variation in the response of the cyanobacterium Nodularia spumigena to moderate UV-B radiation. Harmful Algal Blooms (in press)

Sundbäck, K., Miles, A., Linares, F. (2006) Nitrogen dynamics in non-tidal littoral sediments: role of microphytobenthos and denitrificatiion. Estuaries and Coasts 29: 1196-1211

Linares F. Sundbäck K. (2006) Uptake of dissolved free amino acids (DFAA) by microphytobenthic communities Aquat. Microb. Ecol. 42:175-186

Sundbäck K, McGlathery K (2005) Interactions between benthic macroalgal and microalgal mats. In Kristensen, E. Haese R.R. Kostka, J.E. (eds) Interactions between macro- and microorganisms in marine sediments, AGU Series: Coastal and Estuarine Studies, Vol 60, pp 7-29

Hulth S, Aller RC, Canfield DE, Dalsgaard T, Engström P, Gilbert F, Sundbäck K. Thamdrup B. (2005). N removal in marine environments: recent developments and future research challenges. Mar Chem.94: 125-145

Sundbäck, K., Linares, F., Larson, F., Wulff, A., Engelsen, A. (2004) Benthic nitrogen fluxes along a depth gradient in a microtidal fjord: The role of denitrification and microphytobenthos. Limnol. Oceanogr. 49: 1095-1107.

McGlathery, K., Sundbäck, K., Anderson, I. C. (2004) The importance of primary producers for the benthic nitrogen and phosphorus cycling. In The influence of Primary Producers on Estuarine Nutrient Cycling edited by Nielsen, S.L., G. T. Banta & M. F. Pedersen, Kluwer Academic Publishers. pp. 232-263.

Villafañe V, Sundbäck K, Figueroa FL, Helbling EW (2003) Photosynthesis in the aquatic environment as affected by ultraviolet radiation. In: Helbling EW, Zagarese H (eds) UV effects in organisms and ecosystems. Comprehensive Series in Photosciences, pp. 357-307

Sundbäck, K., Miles, A., Hulth, S., Pihl, L., Engström, P. Selander, E., Svenson, A. (2003): Importance of benthic nutrient regeneration for the initiation of macroalgal blooms in shallow bays. Mar. Ecol. Prog. Ser. 246:115-126.

Sundbäck, K, Miles A. (2002) Role of microphytobenthos and denitrification for nutrient turnover in embayments with floating green algal mats: a spring situation. Aquat Microb Ecol 30:91-101. 

Sundbäck K, Miles A, Gäransson E (2000) Nitrogen fluxes, denitrification and the role of microphytobenthos in microtidal shallow-water sediments: An annual study. Mar. Ecol. Prog. Ser 2000: 59-76

Miles A, Sundbäck K (2000) Diel variation of microphytobenthic productivity in areas with different tidal amplitude. Mar Ecol Prog Ser 205: 11-22

Wulff, A., Wängberg, S.-Å., Sundbäck. K., Nilsson, C., Underwood, G. J. (2000) Effects of UVB-radiation on a marine microbenthic community growing on a sand-substratum under different nutrient conditions. Limnol. Oceanogr. 45: 1144-1152

Vilbaste, S., Sundbäck, K., Nilsson, C. (2000) Distribution of benthic diatoms in the littoral zone of the Gulf of Riga, Baltic Sea. Eur. J. Phycol. 35: 373-385

Popular science:

Sundbäck, K, Miles, A. (2002). What happens with nitrogen in shallow bays? (in Swedish). Havsmiljön 2002: 20.

Other publications

Dalsgaard, T. (ed.), Nielsen, L.P., Brotas, V., Viaroli, P., Underwood, G., Nedwell, D., Sundbäck, K., Rysgaard, S., Miles, A., Bartoli, M., Dong, L., Thornton, D.C.O., Ottosen, L.D.M., Castaldelli, G. & Risgaard-Petersen, N. (2000): Protocol handbook for NICE - Nitrogen Cycling in Estuaries: a project under the EU research programme: Marine Science and Technology (MAST III). National Environmental Research Institute, Silkeborg, Denmark. 62 pp

Hulth S., Sundbäck K. 2009. Consequence analysis of removal of surface sediments in shallow-water coastal bays (in Swedish). Länstyrelsen i Västra Götalands län, Vattenvårdsenheten, Rapport 2009:33

Current administration

Member of the Water Delegation for the Water District of the Swedish West Coast (Vattendelegationen i Västerhavets vattendistrikt) since 2004; appointed by the Swedish Government

Member of the Environmental Research Council, Swedish Environmental Protection Agency, since 2007

Member of the evaluation committee of associate professorships (docentnämnden), Faculty of Science, University of Gothenburg, since 2003-2009

Member of the steering group for the Governmental Task (Regeringsuppdrag)  51b "Restoration of eutrophicated coastal bays in the water district of the Western Seas" 2007-2009

Member of the Data-base Infrastucture Committee (DISC) hosted by VR and KI, since 2008

Examiner (one of three) at the Department of Marine Ecology, Univrsity of Gotheburg

Director of postgraduate studies, Department of Marine Ecology, University of Gothenburg, since 2010