Search for dissertations about: "phytoplankton and primary production"

Showing result 6 - 10 of 45 swedish dissertations containing the words phytoplankton and primary production.

2. 6. Impacts of global change on primary production in northern lakes

   Author : Isolde Callisto Puts; Ann-Kristin Bergström; Jenny Ask; Tom H. Andersen; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Primary production; global change; warming; browning; lake; carbon dioxide; organic carbon; inorganic carbon; boreal; arctic; DOC; DIC; CO2; allochthonous organic carbon; benthic; periphyton; environmental change; miljöförändringar; environmental science; miljövetenskap; biology; biologi; climate change; klimatförändringar;

   Abstract : Algae are primary producers, a major component of the aquatic foodweb, and changes in primary production affect aquatic ecology in general. Global changes such as warming, recovery of acidification and changes in land-use have caused warming and browning of northern lakes. READ MORE

4. 7. 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

5. 8. Direct and indirect effects of fish predation and excretion in aquatic food webs

   Author : José Luiz Attayde; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; marine biology; Hydrobiology; zooplankton; resilience; predation; phytoplankton; nutrient enrichment; nutrient recycling; interaction strength; herbivory; food webs; food chain; excretion; fish; detritus; detritivory; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi;

   Abstract : The aim of this thesis was to elucidate the mechanisms by which planktivorous fish can affect planktonic communities in lakes and how they may affect benthic communities through their effects on planktonic communities. In a laboratory experiment, nutrients released by fish increased algal biomass and altered phytoplankton community structure, suggesting that fish can affect phytoplankton by directly releasing nutrients. READ MORE

6. 9. Turbulence in the sea ice impacted Southern Ocean and its implications for primary production and carbon export

   Author : Isabelle Giddy; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Southern Ocean; sea ice; submesoscale; diapycnal mixing; heat fluxes; primary production; carbon export; gliders.;

   Abstract : The sea ice impacted Southern Ocean, south of the Antarctic Circumpolar Current, is one of the most important regions on earth for the cycling of carbon and distribution of heat and freshwater around the globe. Here, along-isopycnal upwelling of warm, carbon-rich circumpolar deep water coincides with the annual growth and melt of Antarctic sea ice that represents one of the worlds largest surface water transformations. READ MORE

7. 10. Bloom dynamics and population genetics of marine phytoplankton - Community, species and population aspects

   Author : Karolina Härnström; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; phytoplankton; dynamics; Skeletonema marinoi; population genetics; resting stages;

   Abstract : Phytoplankton are the most important primary producers in the world’s oceans and coastal waters, accounting for nearly half of the global net primary production. Although they are such important organisms, little is known about the ecology and dynamics of phytoplankton. READ MORE