Search for dissertations about: "food web interactions"

Showing result 21 - 25 of 63 swedish dissertations containing the words food web interactions.

2. 21. Summer cyanobacterial blooms in the Baltic Sea - implications for copepod recruitment

   Author : Hedvig Hogfors; Sture Hansson; Wim Kimmerer; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Cyanobacteria; Calanoid copepods; Food web interactions; Harmful algae blooms; Zooplankton; Nodularin; Allelopathy; Baltic Sea; Biochemical markers; RNA-based indices; Acidification; Global Climate Change; Marine Ecology; marin ekologi;

   Abstract : During summer, the Baltic Sea is subjected to the world’s largest cyanobacterial blooms. These blooms are linked to eutrophication and raise many questions concerning their effects on the ecosystem. To understand their impacts on the food web dynamics, it is essential to assess growth responses of grazers to these cyanobacteria. READ MORE

4. 22. Fishing for sustainability : Towards transformation of seagrass-associated small-scale fisheries

   Author : Sieglind Wallner-Hahn; Maricela de la Torre-Castro; Christina Hicks; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; small-scale fisheries; co-management; social-ecological systems; ecosystem services; institutions; transformation; seagrass meadows; destructive gear; food-web interactions; marin ekotoxikologi; Marine Ecotoxicology;

   Abstract : Small-scale fisheries employ many millions of people around the world, and are particularly important in developing countries, where the dependency on marine resources is high and livelihood diversification options are scarce. In many areas of the world however, small-scale fisheries are at risk which threatens the food security and wellbeing of coastal people. READ MORE

5. 23. Ecological connectivity in East African seascapes

   Author : Charlotte Berkström; Nils Kautsky; Susan S. Bell; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; fish; functional group; food-web interactions; nursery; coral; seagrass; mangrove; landscape ecology; marin ekotoxikologi; Marine Ecotoxicology;

   Abstract : Coral reefs, seagrass beds and mangroves constitute a complex mosaic of habitats referred to as the tropical seascape. Great gaps exist in the knowledge of how these systems are interconnected. This thesis sets out to examine ecological connectivity, i.e. READ MORE

6. 24. Top-down and bottom-up effects in a Fennoscandian tundra community

   Author : Doris Grellmann; Lars Ericson; Lauri Oksanen; Richard Inouye; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; consumer-resource interactions; exclosures; food web dynamics; grey-sided voles; lemmings; NPK-fertilization; plant defences; reindeer; soil microbes; vertebrate grazing;

   Abstract : The objective of this thesis was to investigate the effects of mammalian grazers, such as microtine rodents and reindeer, (top-down effects) and nutrient availability (bottom- up effects) on the plant community of a tundra heath.I conducted a large-scale fertilization experiment and studied the impact of grazers using exclosures. READ MORE

7. 25. Bottom-up and top-down regulation of heterogeneous lake food webs

   Author : Fernando Chaguaceda; Peter Eklöv; Kristin Scharnweber; Lars Tranvik; Blake Matthews; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; food webs; resource coupling; ontogenetic diet shifts; resource specialization; bottom-up; top-down; browning; eutrophication; lake; mesocosms; fatty acids; apparent competition; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

   Abstract : Food webs are networks of organisms linked by trophic interactions that regulate the responses of ecosystems to environmental change. Such regulation is a result of the effects of resources on the abundance of their consumers (i.e. bottom-up effects) and/or the influence of consumers on the abundance of their resources (i. READ MORE