The diversity of bacteria in nature is enormous. This was only recently discovered due to the development of molecular methods. We now know that bacterial communities change over time and space, but we don’t know why and if it matters for the role of bacteria in ecosystems. In other words we lack basic knowledge about bacterial ecology, and we don’t know if it is fundamentally different compared to ecology of other organisms. This is what I want to find out!
Keywords: limnology lake bacteria diversity
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Previous achievements include a PhD degree in Limnology at Uppsala University in 1999, and a Docent title from the same university in 2004. I have held two postdoc positions, one in 1999-2000 at the Department of Limnology of the Austrian Academy of Sciences and one in 2004 at Université du Québec à Montréal.
During my time at Uppsala University I have been teaching corresponding to 10-50% of a full time position including course development and responsbility for 8 different undergraduate and Masters courses. I have done more than 200 hours of lectures in such courses.
I am a member of the Uppsala University "Mentorskollegium" mentoring young teachers in undergraduate teaching. In my own undergraduate teaching I do lectures, lab introductions, field excursions, project supervision, seminars, computing exercises and web teaching, and I am happy to mentor within all of these methods and techniques, but also in others. In both English and in Swedish. I believe that teaching can be improved when teachers discuss and observe each other and as a mentor I hope to help young teachers to develop their teaching skills and also that I will learns something myself from the interaction.
1) Which factors are shaping microbial diversity?
2) Does the function of the microbial community in the ecosystem depend on the diversity or community composition?
My research is within the field of metacommunities, i.e. to what extent communities and ecosystems are influenced by other communities in the surroundings (i.e. the metacommunity). I am also interested in the importance of bacterial diversity for the functioning of ecosystems, with special focus on the carbon cycle.
The following questions are addressed in current projects:
1) How important is dispersal of bacterial cells for bacterial community composition and functioning? Can massive dispersal of cells (mass effects) over shadow environmental steering factors for community composition? Are other dispersal processes, such as the build-up of seed banks of importance for diversity? Is the sequence of dispersal of importance due to so called priority and monopolization effects? Does the importance of these factors differ over season, among lakes of different types and among organism groups? What are the consequences of dispersal for the functioning of bacterial communities?
2) Does the functional performance of bacterial communities and populations with regards to organic carbon usage depend on taxonomy or adaptation?
In general questions about biogeography and biodiversity-ecosystem function relationships have been little addressed in microbial communities due to methodological constraints. Today we use novel DNA-sequencing techniques. This development has opened up the door for a new set of questions since diversity can be analysed to a great precision and depth. Finally we can address the over-all question of if microorganism biogeography and biodiversity follow similar rules as that of larger organisms or if they are fundamentally different. Only future will tell if this information will make us rewrite ecology textbooks!
Further, this research aims to increase our understanding of the role of bacteria in ecosystems, where they play central roles in for instance carbon cycling. Thus, my research deals with the small players with global impact.
Recent and current projects have been made possible by financial support from for instance Vetenskapsrådet, The Wenner-Gren foundation, Carl Tryggers Stiftelse för Vetenskaplig forskning, Stiftelsen Oscar och Lili Lamms minne, Biodiversa, and Stiftelsen Olle Engkvist Byggmästare.
Karen Lebret (Ecological tipping points, bacteria and phytoplankton interactions)
Martin Andersson (The role of adaptation of bacterial traits in diversity-ecosystem relationships)
Theresa Lumpi (community assembly)
Yinghua Zha (Fish gut microbiota, main supervisor Richard Svanbäck)
Rhiannon Mondav (Ecoinformatics of freshwater Pelagibacteriaceae, main supervisor Stefan Bertilsson)
Máté Vass (Microbial community assembly, main supervisor Silke Langenheder)
Previous group members
Jürg Brendan Logue (PhD student, biogeography)
David Lymer (PhD student, viral ecology)
Xinmei Feng (postdoc, biogeography)
Jérôme Comte (postdoc, biogeography)
Ina Severin (postdoc, diversity and function from a biogeography perspective)
Johanna Sjöstedt (Microbial diversity and ecosystem functioning)
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