Sökning: "marin ekologi"

Visar resultat 1 - 5 av 267 avhandlingar innehållade orden marin ekologi.

  1. 1. Function and dynamics of woody debris in boreal forest streams

    Författare :Niklas Dahlström; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Ecology; Boreal forest; CPOM; CWD; forest management; geomorphology; LWD; riparian forest; retention; residence time; streams; Sweden; woody debris; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Terrestrisk; limnisk och marin ekologi;

    Sammanfattning : The work in this thesis deals with (1) the effects of woody debris on stream channel morphology and retention of organic material, and (2) the dynamics of woody debris and its relation to riparian forest history and composition. The studied stream reaches are situated in mature, productive forests in the boreal zone of Sweden. LÄS MER

  2. 2. Non-indigenous zooplankton : the role of predatory cladocerans and of copepods in trophic dynamics

    Författare :Marc Andersen Borg; Fredrik Wulff; Markku Viitasalo; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Acartia tonsa; Bythotrephes longimanus; Cercopagis pengoi; egg production; fitness; food web changes; ingestion rates; invasive species; metabolic balance; mortality; non-indigenous zooplankton; predation impact; salinity tolerance; stable isotopes; Marine ecology; Marin ekologi; marin ekologi; Marine Ecology;

    Sammanfattning : Human-mediated introductions of non-indigenous species now threaten to homogenize the biota of the Globe, causing huge economic and ecological damage. This thesis studies the ecological role of 3 invasive planktonic crustaceans, the omnivorous copepod Acartia tonsa (western Atlantic and Indo-Pacific) and the predatory cladocerans, Cercopagis pengoi (Ponto-Caspian) and Bythotrephes longimanus (Eurasian). LÄS MER

  3. 3. The neglected ecology of the sand goby: Abundance and feeding in the Baltic sublittoral

    Författare :Sigrid Z. Ehrenberg; Ragnar Elmgren; Sture Hansson; Gunilla Ejdung; Erik Bonsdorff; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; sand goby; sublittoral; sub-thermocline; abundance; feeding; consumption; activity; Marine ecology; Marin ekologi; marin ekologi; Marine Ecology;

    Sammanfattning : I investigated the ecology and population density of the sand goby, Pomatoschistus minutus, at sub-thermocline depth in the north-western Baltic proper. Most previous research on the sand goby, and the co-occurring closely related common goby, P. LÄS MER

  4. 4. Effects of habitat structure on tropical fish assemblages

    Författare :Kajsa Garpe; Marcus Öhman; Geoffrey Jones; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Marine ecology; Marin ekologi; marin ekologi; Marine Ecology;

    Sammanfattning : Rates of habitat alteration and degradation are increasing worldwide due to anthropogenic influence. On coral reefs, the loss of live coral reduces structural complexity while facilitating algal increase. In many coastal lagoons seagrass and corals are cleared to make room for cultivated macroalgae. LÄS MER

  5. 5. Zooplankton growth and trophic linkages : Implications for fish feeding conditions in the Baltic Sea

    Författare :Towe Holmborn; Elena Gorokhova; Sture Hansson; Ilppo Vuorinen; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; AARS activity; biochemical markers; Clupea harengus; copepod physiology; food web interactions; non-indigenous species; RNA-based indices; Sprattus sprattus; stable isotopes; Marine ecology; Marin ekologi; marin ekologi; Marine Ecology;

    Sammanfattning : The aim of this Thesis was to improve our understanding and assessment of feeding conditions for zooplanktivorous fish in the Baltic Sea.We investigated (papers I, II) the usefulness of biochemical proxies for assessments of growth and metabolic rates in the dominant Baltic copepod Acartia bifilosa. LÄS MER