Sökning: "Seston stoichiometry"

Hittade 5 avhandlingar innehållade orden Seston stoichiometry.

1. 1. The Invasion of the Zebra Mussel - Effects on Phytoplankton Community Structure and Ecosystem Function

   Författare :Rahmat Naddafi; Kurt Pettersson; Peter Eklöv; Willem Goedkoop; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Invasive species; Zebra mussel; Invasion success; Selective feeding; Non-lethal effects of predator; Seston stoichiometry; Delayed fluorescence excitation spectroscopy; Phytoplankton dynamics; Trait-mediated indirect interaction; Ecosystem function;

   Sammanfattning : Biological invasion has become a major threat to economy, ecology, global biodiversity and ecosystem function of aquatic ecosystems. The main aim of the thesis was to study the effects of the zebra mussel (Dreissena polymorpha), a versatile invasive species, on phytoplankton dynamics and ecosystem function of lakes. LÄS MER

3. 2. Effects of inorganic nitrogen and organic carbon on pelagic food webs in boreal lakes

   Författare :Anne Deininger; Ann-Kristin Bergström; Jan Karlsson; Antonia Liess; Carolyn L. Faithfull; John A. Downing; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; autochthony; basal production; boreal; global change; dissolved organic carbon; food web efficiency; N deposition; phytoplankton; seston stoichiometry; whole lake enrichment; zooplankton; limnologi; Limnology;

   Sammanfattning : Anthropogenic activities are increasing inorganic nitrogen (N) loadings to lakes in the northern hemisphere. In many boreal lakes phytoplankton are N limited, wherefore enhanced N input may affect the productivity of pelagic food webs. LÄS MER

4. 3. Food Quality Effects on Zooplankton Growth and Energy Transfer in Pelagic Freshwater Food Webs

   Författare :Jonas Persson; Tobias Vrede; Peter Eklöv; Ellen van Donk; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; elemental stoichiometry; phosphorus; polyunsaturated fatty acids; EPA; oligotrophic lakes; empirical modelling; Daphnia; Cladocera; Copepoda; Ekologi;

   Sammanfattning : Poor food quality can have large negative effects on zooplankton growth and this can also affect food web interactions. The main aims of this thesis were to study the importance of different food quality aspects in Daphnia, to identify potentially important differences among zooplankton taxa, and to put food quality research into a natural context by identifying the importance of food quality and quantity in lakes of different nutrient content. LÄS MER

5. 4. Consequences of consumer-resource stoichiometric imbalance in planktonic food webs

   Författare :Junwen Guo; Mehdi Cherif; Tanguy Daufresne; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; environmental science; miljövetenskap;

   Sammanfattning : Resource imbalance between consumers and their resources can come from inadequate resource quantity or quality. The ecological stoichiometry theory focuses on understanding the consequences of imbalance in elemental composition.  In this thesis, I have used both resource quality (e.g. LÄS MER

7. 5. Nutrient limitation and elemental ratios in Baltic Sea plankton

   Författare :Jakob Walve; Karin Lochte; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plankton; Östersjön; Ekosystem i vatten; Systems Ecology; systemekologi;

   Sammanfattning : Phytoplankton growth is frequently limited by the supply of nitrogen (N), phosphorus (P), or sometimes other elements. N2-fixing cyanobacteria are favoured by N limitation, which they may alleviate by adding new N to the ecosystem. LÄS MER