Sökning: "flagellates"

Visar resultat 1 - 5 av 16 avhandlingar innehållade ordet flagellates.

1. 1. Flagellates in the marine microbial food web : the ecology of a mixotrophic nanoflagellate, Ochromonas sp

   Författare :Agneta Andersson-Nordström; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Microbial food web; flagellates; Ochromonas sp.; mixotrophy; size- selective grazing; remineralisation; excretion of DFAA;

   Sammanfattning : Nanoflagellates were found to be abundant in a coastal area of the northern Bothnian Sea. The maximum concentration of nanoflagellates, approximately 8000 cells ml-1, was observed in July, coinciding with a decrease in the abundance of cyanobacteria. LÄS MER

3. 2. Mechanisms structuring the pelagic microbial food web : Importance of resource and predation

   Författare :Kristina Samuelsson; Agneta Andersson; Christiane Lancelot; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; pelagic microbial food web; bacteria; flagellates; ciliates; phytoplankton; mixotrophy; nutrient status; predation limitation; resource limitation; Baltic Sea; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : Temporal and spatial variations of pelagic microorganisms in the northern Baltic Sea were studied, as well as factors influencing their abundance and growth rates. Three main questions were asked 1) How does increased productivity influence the structure of the microbial food web? 2) Does predation limitation vary between trophic levels? 3) What is the relative importance of resource and predation limitation at different trophic levels?A field study in the northern Baltic Sea showed that dominating protozoa, flagellates and ciliates, increased with increasing primary productivity from north to south. LÄS MER

4. 3. The importance of terrestrial carbon in plankton food webs

   Författare :Cesar Bolivar Daniel; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ecology; lakes; carbon; zooplankton; Spumella elongata; Poterioochromonas malhamensis; flagellates; bacteria; stable isotopes; photochemistry; autochthonous; DOC; allochthonous; plankton; Ekologi; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : Allochthonous substances, i.e. produced in terrestrial ecosystems, are known to fuel bacterial production in humic lakes. I observed that allochthonous carbon subsidizes bacteria even at high levels of phytoplankton biomass. LÄS MER

5. 4. Pelagic microorganisms in the northern Baltic Sea : Ecology, diversity and food web dynamics

   Författare :Johnny Berglund; Agneta Andersson; Ramon Massana; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; resource limitation; predation limitation; microbial food web; heterotrophic microorganisms; nanoflagellates; ciliates; protists; resource heterogeneity; chrysomonads; chrysophytes; group-specific PCR-DGGE primers; Baltic Sea; Marine ecology; Marin ekologi;

   Sammanfattning : Heterotrophic microorganisms are important for the flow of carbon and nutrients in the sea. Bacteria, nanoflagellates and ciliates are relevant components of the pelagic food web. In order to be able to predict the outcome of e.g. LÄS MER

7. 5. Distribution and fate of polychlorinated biphenyls within the pelagic microbial food web

   Författare :Petra Wallberg; Per Larsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Biologi; zoologi; Zoology;

   Sammanfattning : The composition and production of the plankton community in aquatic environments will in turn influence the food-web structure of larger predators, nutrient cycling, the sinking flux and, hence, the fate of hydrophobic organic contaminants. The aim of the research presented here was to study the distribution and fate of PCBs within the microbial food web, including bacteria, flagellates, ciliates, and phytoplankton. LÄS MER