Search for dissertations about: "trophic control"

Showing result 1 - 5 of 33 swedish dissertations containing the words trophic control.

2. 1. Multiple forces drive the Baltic Sea food web dynamics and its response to environmental change

   Author : Susa Niiranen; Thorsten Blenckner; Olle Hjerne; Mike Elliott; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; climate change; Ecopath with Ecosim; food web interactions; multiple drivers; regime shift; trophic control; Marine Ecology; marin ekologi;

   Abstract : Understanding the interaction of multiple drivers and their compounded effects on ecosystem dynamics is a key challenge for marine resource management. The Baltic Sea is one of the world’s seas most strongly impacted by effects from both human activities and climate. READ MORE

4. 2. 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

5. 3. Effects of warming on the ecology of algal-dominated phytobenthic communities in the Baltic Sea

   Author : Filip Svensson; Pauline Snoeijs; Johan Eklöf; Hans Kautsky; Nils Ekelund; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; climate change; warming; photosynthesis; trophic cascades; pigments; community traits; temperature gradient; invasive mussel; Marine Ecology; marin ekologi;

   Abstract : Through climate change, the global average air and surface water temperature has risen 0.85°C during the last 100 years. The Baltic Sea experienced one of the most rapid increase in temperature recorded of marine ecosystems. READ MORE

6. 4. Towards understanding stable isotope signatures in stressed systems

   Author : Caroline Ek; Elena Gorokhova; Katrine Borgå; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Stable isotope analysis; trophic position; chemical exposure; oxidative stress; Daphnia magna; Gammarus spp.; Limecola balthica; Applied Environmental Science; tillämpad miljövetenskap;

   Abstract : Stable isotope analysis (SIA) is a valuable tool in ecotoxicology because δ13C and δ15N may provide insights into the trophic transfer of contaminants in a food web. The relationship between a species’ trophic position (TP, determined from δ15N) and internal concentration of biomagnifying contaminants can be established and used for regulatory purposes. READ MORE

7. 5. Effects of temperature and terrestrial carbon on primary production in lake ecosystems

   Author : Mohammed Hamdan; Jan Karlsson; Pär Byström; Erin R. Hotchkiss; Lars-Anders Hansson; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; lakes; primary production; benthic; pelagic; carbon dioxide limitation; light limitation; nutrient limitation; browning; warming; allochthonous carbon; grazing; trophic cascades;

   Abstract : Climate warming is predicted to affect northern lake food webs in two ways: (1)directly via changes in water temperature and ice conditions, and (2) indirectlyvia changes in catchment characteristics and processes that influence input ofallochthonous coloured dissolved organic matter (cDOM) and nutrients. Input ofcDOM increases carbon dioxide (CO2) availability, causes brownification andreduced light conditions, and may increase nutrient availability especially forpelagic primary producers. READ MORE