Research interests

Water quality: My research interests are strongly influenced by the time of my diploma thesis, where I dealt with a hypertrophic lake in Leipzig. In this lake cyanobacterial blooms and a massive fish kill with 11 tons of dead fish occurred. I am fascinated by the fact that although a lake contains extensive nutrients, during the phase of cyanobacterial blooms, diversity of other phytoplankton species is very low. I want to gain insights into which factors make it possible that diversity is suppressed and reversed, under which circumstances diversity can be supported.

Phytoplankton organisms are ideal candidates to study diversity due to their fast growth. These organisms are microscopic small but have an enormous impact on the water quality and ecology. Their ability to convert light energy to biomass via photosynthesis determines the extent of primary production. Phytoplankton species can be distinguished due to their different pigmentation patterns by the means of flow cytometry. Imaging flow cytometry delivers the following cellular traits: cell volume, dry weight and chl a-content per cell and also the variability of these traits within a population. It is also possible to examine multi-species experiments with a fast species identification.

Air quality and pollination: Pollen are a fascinating biological material; small in size, but highly protected against different external environmental factors (heat, various chemicals, UV-light) to guarantee a proper maintenance of a whole set of genetic information. Pollen diversity is linked to several ecosystem services, like air quality and pollination success.

We will consider air quality as being impaired by allergic pollen (wind distributed pollen) and their health consequences of combined biological and physical impacts of human activities manifested through changes in plant species pollen abundance and particulate matter resulting in air pollution. Second, pollination is impaired by insect death and changes in plant-pollinator interactions (insect distributed pollen). To understand the relationships between pollen abundance, particulate matter, incidence of allergy symptoms as well as plant-pollinator interactions, we propose to develop and integrate new methods in particle analysis, machine learning, monitoring and sensing, and to develop a larger joint project with societal engagement.

Articles

• Dunker, S. (2014): The Cell Biology of Cyanobacteria, E. Flores, A. Herrero (Eds.). Caister Academic Press, Norfolk, UK (2014), Book review on: 308 pp., GBP 159.00, USD 319.00, ISBN: 978-1-908230-38-6, Journal of Plant Physiology, Vol. 171 (16): 1453
• Lentendu, G., Hübschmann T., Müller S., Dunker S., Buscot F., Wilhelm C. (2013) Recovery of soil unicellular eukaryotes: an efficiency and activity analysis on the single cell level. Journal of Microbiological Methods, Vol. 95 (3):463-469
• Dunker, S., Jakob, T., Wilhelm, C. (2013) Contrasting effects on the growth of two green algae (Oocystis marssonii, Scenedesmus obliquus) during cocultivation with Microcystis aeruginosa revealed by flow cytometry. Freshwater Biology, Vol. 58: 1573-1587
• Wagner, H., Dunker, S., Liu, Z., Wilhelm, C. (2013) Subcommunity FTIR to determine physiological cell states. Current Opinion in Biotechnology 24 (1): 88-94

Oral Presentations

       Invited oral presentations

• Limnological Stammtisch Leipzig, 17 April 2018 (organized by Dr. Ingrid Carmienke: "Advanced image flow cytometry as a new tool in phytoplankton research")

• Hydrobiological seminar TU Dresden, 16  November 2017 (Working group Prof. Dr. T. Berendonk: High throughput-analysis of phytoplankton by imaging flow cytometry/ Cyanobacteria dominance reinforced by climate change?)

• Limnological station Iffeldorf TU München, 07 November 2012 (Working group Prof. Dr. Melzer: Phytoplankton dynamic under hypertrophic conditions)

• Dunker, S. (2010) „Flow cytometry for phytoplankton analysis with taxonomic resolution“, Meeting of the German Society for Cytometry, Leipzig
• Dunker, S. (2012) “The influence of interspecific effects on phytoplankton primary production”, Meeting of Plant Physiologists of Saxony, Saxony-Anhalt and Thuringia, Jena
• Dunker, S. (2012) “Interspecific effects on growth and primary production in mixed culture of the green algae O. marssonii and the cyanobacterium M. aeruginosa”, Meeting of the Phycology Section of the German Botanical Society, Wuppertal
• Dunker, S.; Jakob, T.; Nadrowski, K., Wilhelm, C. (2013) „Distinctive habitat preferences for major phytoplankton groups in a hypertrophic lake“, Meeting of the German Society for Limnology, Potsdam
• Dunker, S. (2015) "Phenotypic plasticity and community dynamics of phytoplankton organisms", Meeting of the German Society for Cytometry, Berlin
• Dunker, S. (2016) "Flow cytometry as a powerful tool in biodiversity research", iDiv conference, Leipzig
• Dunker, S. (2017) "Image-based flow cytometry as missing link in phytoplankton biodiversity research", DynaTrait conference, Hannover
  
• Dunker, S., Harpole, S. (2017) "Microscale diversity of the eukaryotic domain - Morphological and physiological traits in the size range of 1-100 µm ", iDiv conference, Leipzig
• Dunker, S. (2018) "Advanced imaging flow cytometry as a new tool in phytoplankton research", Meeting of the Phycology Section of the German Botanical Society, Berchtesgaden
  
• Dunker, S., Wäldchen, J., Boho, D., Mäder, P., Harpole, W.S. (2018) "Who am I and if yes, how many? A new way of phytoplankton species identification by combination of image cytometry and deep learning", Meeting of the German Society for Cytometry, Jena
  
• Dunker, S. (2018) "Tiny, but mighty - Innovative monitoring strategies for pollen and phytoplankton diversity", iDiv conference, Leipzig

Poster

• Dunker, S., Wilhelm, C. (2009) “Co-cultivation of algae and effects on their growth and physiology”, Meeting of the German Botanical Society Leipzig
• Dunker, S., Liu, Z., Nadrowski, K., Wilhelm, C. (2011) „Taxonomisch aufgelöste Biomassemodellierung von Phytoplankton“, Meeting of the German Society for Limnology, Freising
• Dunker, S., Wilhelm, C. (2011) “Comparative study of mono-culture and mixed culture of the green algae Oocystis marssonii and the cyanobacterium Microcystis aeruginosa”, Meeting of the German Botanical Society, Berlin
• Dunker, S., Jakob, T. Wilhelm, C. (2014) „Quantification of co-cultivation effects on phytoplankton species“, Meeting of the Phycology Section of the German Botanical Society, Stralsund
• Dunker, S. (2015) "Flow cytometry for high-throughput analysis of phytoplankton", iDiv conference, Leipzig
  
• Dunker, S., Harpole, S. (2017) "Microscale diversity of the eukaryotic domain - Morphological and physiological traits in the size range of 1-100 µm ", iDiv conference, Leipzig
• Dunker, S., Harpole, W.S., Wilhelm, C. (2017) "Image-based flow cytometry for high throughput analysis of phytoplankton", ASLO - Aquatic Sciences Meeting, Honolulu
• Dunker, S., Althammer, J., Pohnert, U., Neu, T., Jakob, T., Wilhelm, C., Harpole, W. S. (2018) "Fateful meetings of unicellular green algae and the cyanobacterium M. aeruginosa", ISME conference/ International Symposium on Microbial Ecology, Leipzig
  
• Dunker, S., Boho, D., Wäldchen, J., Bumberger, J., Mäder, P., Harpole, W.S. (2018) "Improved environmental monitoring of air and water quality by combination of high-throughput imaging flow cytometry and deep learning", International Conference on Ecological Informatics, Jena
  

PhD thesis

• Dunker, S. (2013) Phytoplankton dynamic under hypertrophic conditions, University of Leipzig, Department of Plant Physiology

Diploma thesis

• Dunker, S. (2008) “Estimation of Chl a-specific absorption coefficient of phytoplankton on taxon level”, University of Leipzig, Institute of Biology, Department of Plant Physiology

Dunker 2019: „VORRICHTUNG ZUR AUTOMATISCHEN SPEZIESANALYSE UND VERFAHREN ZU DESSEN DURCHFÜHRUNG“ WO 2019/068352 A 1

EP / US

Reviewer activities

• Aquatic Microbial Ecology
• Citizen Science Theory Practice
  
• Current Microbiology
• Critical Reviews in Biotechnology
• Cytometry Part A
• Czech Science Foundation
  
• Ecology
• Ecology and Evolution
  
• Ecotoxicology
• Environmental Engineering Science
  
• Freshwater Biology
• Journal of Applied Ecology
• Journal of Plant Physiology
• LIMNOLOGY and OCEANOGRAPHY
  
• Nature - Scientific Reports
• NSF
• Themenhefte Allergologie
  
• WATER

Memberships

• Member of German Society for Cytometry (DGfZ)
  
• Member of German Society for Limnology (DGL)
  
• Member of German Society for Phycology

Engagement in the Environmental Committee of UFZ

• Leader of working committee: Reduction of plastic in laboratories

      Activities: Information stand UFZ summer party, Participation in Let`sCleanUpEurope, Participation in Long Night of Sciences (in Halle 2017)  

PolDiv (Automated high throughput pollen diversity monitoring of air quality and pollination as ecosystem services)

PhyCosms (Phytoplankton microcosms)

Quantification of allelopathic growth effects in mono- and mixed cultures of microalgae (Bachelor thesis, Johanna Knechtel, 2017)

Biodiversity provisioning resilience along environmental gradients (PhD thesis, Peter Hofmann, 2016-...)