Search for dissertations about: "Microbial food web"

Showing result 6 - 10 of 32 swedish dissertations containing the words Microbial food web.

  2. 6. Food web dynamics in open and closed systems

    Author : Johan Lövgren; Lennart Persson; Jonathan Chase; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; allochtonous input; cross habitat foraging; donor control; heterogeneity within trophic level; compensation; food web; littoral; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Abstract : This thesis is a summary of enclosure and microcosm experiments that aimed to study the impact of allochtonous subsidies on food web dynamics in a heterogeneous food web. In the enclosure studies, a three trophic level littoral food web was used. READ MORE

  4. 7. The aquatic microbial food web and occurence of predation-resistant and potentially pathogenic bacteria, such as Francisella tularensis

    Author : Johanna Thelaus; Agneta Andersson; Mats Forsman; Farooq Azam; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; bacteria; protozoa; ecology; predation; nutrient-availability; microbial food web; model; predation-resistance; Francisella; reservoir; biofilm formation; Freshwater ecology; Limnisk ekologi;

    Abstract : All natural aquatic systems harbour a vast variety of microorganisms. In the aquatic microbial food web, the larger microorganisms (i.e. protozoa) feed on the smaller microorganisms (i. READ MORE

  5. 8. Effects of temperature and terrestrial carbon on fish growth and pelagic food web efficiency

    Author : Robert Lefébure; Ulf Båmstedt; Pär Byström; Stefan Larsson; Agneta Andersson; Lars-Gösta Rudstam; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Attack rates; Bacterial production; Climate change; Critical resource density; Growth rates; Microbial food web; Three-spined stickleback;

    Abstract : Both temperature and terrestrial dissolved organic carbon (TDOC) have strong impacts on aquatic food web dynamics and production. Temperature affects vital rates of all organisms and terrestrial carbon has been shown to alter the dynamics of phytoplankton and bacterial production and affect the trophic structure of planktonic food webs. READ MORE

  6. 9. Food web structures and carbon transfer efficiencies in a brackish water ecosystem

    Author : Kristin Dahlgren; Ulf Båmstedt; Agneta Andersson; Marja Koski; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Carbon transfer efficiency; Food web efficiency; zooplankton; production; pelagic; benthic; fatty acids; wax esters; Marine ecology; Marin ekologi;

    Abstract : Two differently structured food webs can be distinguished in the pelagic habitat of aquatic systems; the classical one (autotrophic) with phytoplankton as a base and the microbial food web (heterotrophic) with bacteria as a base. Energy (produced at the basal trophic level) reaches higher trophic levels, i.e. READ MORE

  7. 10. The role of terrestrial and phytoplankton-derived organic matter in planktonic food webs

    Author : Anja Wenzel; Ann-Kristin Bergström; Tobias Vrede; Maarten Boersma; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Daphnia; phytoplankton; heterotrophic bacteria; terrestrial particulate organic material; food quality; food quantity; fatty acids; oligotrophic; Light:Nutrient-Hypothesis; limnologi; Limnology;

    Abstract : Lakes are important global ecosystems and many of them are nutrient-poor (unproductive). Especially in northern boreal latitudes, lakes may be heavily subsidized by terrestrial organic material (t-OM) from peat layers in the catchment. READ MORE