Digital Comprehensive Summaries of Uppsala Dissertations 
                         from the Faculty of Science and Technology 2159 
                         An exploration of freshwater 
                         microbial ecology 
                         from streamlined genera to global networks 
                         RHIANNON MONDAV 
           ACTA 
       UNIVERSITATIS     ISSN 1651-6214 
        UPSALIENSIS      ISBN 978-91-513-1523-2 
          UPPSALA        URN urn:nbn:se:uu:diva-472455 
            2022 
         Dissertation presented at Uppsala University to be publicly examined in Ekmansalen, 
         EBC, Norbyvägen 18, Uppsala, Friday, 10 June 2022 at 13:00 for the degree of Doctor of 
         Philosophy. The examination will be conducted in English. Faculty examiner: Professor 
         Phyllis Lam (University of Southampton). 
         Abstract 
         Mondav, R. 2022. An exploration of freshwater microbial ecology. from streamlined genera 
         to global networks. Digital Comprehensive Summaries of Uppsala Dissertations from the 
         Faculty of Science and Technology 2159. 56 pp. Uppsala: Acta Universitatis Upsaliensis. 
         ISBN 978-91-513-1523-2. 
         Microbes  are  the  main  drivers  of  biogeochemical  cycles  on  Earth  and  even  though 
         freshwaters cover only a small area of terrestrial surfaces their contribution to global cycles 
         is  important.  Global  cycles  are  measured  by  exchanges  between  systems  e.g.  water  to 
         atmosphere or lithosphere and are mediated by microbial communities. Cyanobacteria and 
         other photosynthetic microbes can be highly abundant going through cyclic blooms. These 
         blooms are attributed to their ability to harness sunlight and CO2 to outgrow competitors by 
         using their complex and expensive to produce photosystems. In contrast there are microbial 
         lineages termed ‘streamlined’, that are just as abundant as cyanobacteria at times, but who 
         have much smaller cells, small genomes, and grow and replicate slowly. It is not immediately 
         apparent how microbes with such different lifestyles can have similar ‘success’. By investigating 
         individual streamlined lineages and their interactions we see that they appear to have co-evolved 
         dependencies with each other and are highly successful as consortia. By comparing consortia 
         from different lakes we see that streamlined microbes can sit either adjacent or in the middle of 
         carbon cycling end-points and may be more directly involved than thought in mediating methane 
         and CO2 ratios. An analysis of global inland water microbiomes finds that around one third of 
         the core microbial lineages in inland waters are streamlined. 
         Keywords: microbiology, ecology, networks, streamlined, aquatic 
         Rhiannon Mondav, Department of Ecology and Genetics, Limnology, Norbyv 18 D, Uppsala 
         University, SE-75236 Uppsala, Sweden. Science for Life Laboratory, SciLifeLab, Box 256, 
         Uppsala University, SE-75105 Uppsala, Sweden. 
         © Rhiannon Mondav 2022 
         ISSN 1651-6214 
         ISBN 978-91-513-1523-2 
         URN urn:nbn:se:uu:diva-472455 (http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-472455) 
        
                                       
                                  To Astrid  
                                       
                    may you live long and be so very prosperous  
                                       
                          in ways of your own choosing