Search for dissertations about: "FOOD-WEB"

Showing result 11 - 15 of 144 swedish dissertations containing the word FOOD-WEB.

  2. 11. Food Web Ecology -- individual life-histories and ecological processes shape complex communities

    Author : Martin Hartvig; Evolutionär ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; food web; community ecology; community assembly; size-structure; life-history omnivory; ontogeny; trophic interactions; trait based model; topology; emergent organisation; size-spectrum;

    Abstract : This thesis sets out a food web framework for size-structured populations. The framework enables an ecological approach to food web modelling as the individual life-history from birth, through maturation, and ultimately death is explicitly resolved with the use of bioenergetics based on individual body size. READ MORE

  4. 12. 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

  5. 13. Uptake Processes of Polychlorinated Biphenyls at the Base of the Pelagic Food Web

    Author : Anna Sobek; Örjan Gustafsson; Derek Muir; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; PCBs; plankton; equilibrium partitioning; uptake; aquatic food web; Environmental chemistry; Miljökemi;

    Abstract : Hydrophobic organic contaminants (HOCs) are persistent, toxic to biota and are known to bioaccumulate in food webs. In this thesis, polychlorinated biphenyls (PCBs) were used as model compounds to study the fate and transport of HOCs in the aquatic environment. READ MORE

  6. 14. Hydroxylated polybrominat­ed diphenyl ethers in Baltic Sea biota : Natural production, food web distribution and biotransformation

    Author : Dennis Lindqvist; Lillemor Asplund; Walter Vetter; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; OH-PBDEs; Baltic Sea; Biosynthesis; Environmental fate; Wildlife exposure; Metabolism; Analytical methods; Ceramium tenuicorne; Blue mussel; Gammarus spp.; Stickleback; Perch; Grey Seal; miljökemi; Environmental Chemistry;

    Abstract : Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are naturally produced in aquatic ecosystems e.g. by algae. Many OH-PBDEs have been observed to be highly bioactive and to cause adverse effects through several pathways, e. READ MORE

  7. 15. 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