Sökning: "fiskar"

Visar resultat 21 - 25 av 54 avhandlingar innehållade ordet fiskar.

  1. 21. Pikeivory: behavioural mechanisms in northern pike piscivory

    Författare :Anders Nilsson; Enhet akvatisk ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; northern pike; cannibalism; kleptoparasitism; predation; optimal foraging; Animal ecology; Djurekologi;

    Sammanfattning : Optimal foraging and prey preference in top predators may affect population and community dynamics and structure. Also, optimal foraging and prey preference may shift with prevailing conditions, and therefore create changes in the effect of predation. LÄS MER

  3. 22. Assessment and reduction of the conflicts between commercial fisheries and grey seals (Halichoerus grypus) in Swedish waters

    Författare :Arne Fjälling; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; conflict; fishery; grey seal; mitigate; predation; salmon; trap; konflikt; fiskeri; gråsäl; skadeförebyggande; predation; lax; fälla;

    Sammanfattning : Along with the recovery of the Baltic Sea grey seal population from very low figures in the late 1970 's, there were clear signs of a rapidly increasing conflict between grey seals and fisheries. The set trap fisheries for salmonids seemed to be suffering the worst, but such data as were available were bard to evaluate. LÄS MER

  4. 23. Palaeoenvironments, palaeoecology and palaeobiogeography of Late Cretaceous (Campanian) faunas from the Kristianstad Basin, southern Sweden, with applications for science education

    Författare :Elisabeth Einarsson; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; palaeoenvironments; palaeoecology; palaeobiogeography; Campanian; Kristianstad Basin; Teaching and Learning;

    Sammanfattning : This thesis is thematically divided into two sections: Part1 presents studies related to the palaeoenvironments,palaeoecology and palaeobiogeography of the LateCretaceous (Campanian) faunas from the KristianstadBasin of southern Sweden; Part 2 reports on applicationsof palaeontological research for science education inschools.Part 1 was based on personally conducted fieldworkand biostratigraphical analysis at various Santonian-Campanian localities throughout Skåne. LÄS MER

  5. 24. Paleoenvironments, palaeoecology and palaeobiogeography of late cretaceous (campanian) faunas from the Kristianstad basin, southern Sweden, with applications for science education

    Författare :Elisabeth Einarsson; Benjamin Kear; Vivi Vajda; Jesper Milàn; Lund University; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; NATURVETENSKAP; SAMHÄLLSVETENSKAP; NATURAL SCIENCES; SOCIAL SCIENCES; palaeoenvironments; palaeoecology; palaeobiogeography; Campanian; Kristianstad Basin; Teaching and Learning;

    Sammanfattning : This thesis is thematically divided into two sections: Part1 presents studies related to the palaeoenvironments,palaeoecology and palaeobiogeography of the LateCretaceous (Campanian) faunas from the KristianstadBasin of southern Sweden; Part 2 reports on applicationsof palaeontological research for science education inschools.Part 1 was based on personally conducted fieldworkand biostratigraphical analysis at various Santonian-Campanian localities throughout Skåne. LÄS MER

  7. 25. Effects of dissolved humic matter on phytoplankton

    Författare :Jessica von Einem; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; phytoplankton; PAR; DOC; Water colour; production;

    Sammanfattning : Water colour is currently increasing in thousands of lakes in the northern hemisphere due to an increased input of terrestrial dissolved organic carbon (DOC), and more specifically coloured disscolved humic matter (DHM). I studied how water colour affects the light climate in the epilimnion and, as a consequence, phytoplankton biomass, species composition and production in lakes in southern Sweden. LÄS MER