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Visar resultat 1 - 5 av 56 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Cascading extinctions in food webs : local and regional processes

    Författare :Anna Eklöf; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cascading extinctions; complexity; connectance; dispersal; food web; local dynamics; regional dynamics; resistance; spatial structure; species loss;

    Sammanfattning : Ecological communities all over the world are loosing biodiversity due to different kinds of human activities and there is an urgent need of understanding how those losses affect the function of the ecosystems on which we all depend. The community's response to species losses is likely to depend on both the structure of the local community as well as its interactions with surrounding communities. LÄS MER

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

    Författare :Martin Hartvig; Evolutionär ekologi; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  4. 3. Food Webs, Models and Species Extinctions in a Stochastic Environment

    Författare :Patrik Karlsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ekologi; Ecology; functional redundancy; trophospecies; species aggregation; environmental stochasticity; interaction strength; spectral colour; food web structure; food webs; extinction risk;

    Sammanfattning : In light of the current global mass extinction of species, ecologists are facing great challenges. In order to reverse the path towards additional extinctions early warning systems to guide management actions need to be developed. LÄS MER

  5. 4. Baltic Sea food web dynamics and response to environmental change

    Författare :Susa Niiranen; Thorsten Blenckner; Olle Hjerne; Magnus Huss; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; food web; modelling; Ecopath with Ecosim; model uncertainty; Marine Ecology; marin ekologi;

    Sammanfattning : The Baltic Sea ecosystem is subject to a combination of external pressures such as fishery, changing climate and land-based nutrient inputs. In combination with internal food web mechanisms these external forces can lead to changes in the food web structure and function. LÄS MER

  7. 5. Species extinctions in food webs : local and regional processes

    Författare :Anna Eklöf; Bo Ebenman; Peter Münger; Marcel Holyoak; Linköpings universitet; []
    Nyckelord :Extinction; food web; metacommunity; dispersal; species loss; migration; habitat fragmentation; connectance; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : Loss of biodiversity is one of the most severe threats to the ecosystems of the world. The major causes behind the high population and species extinction rates are anthropogenic activities such as overharvesting of natural populations, pollution, climate change and destruction and fragmentation of natural habitats. LÄS MER