Search for dissertations about: "detritus"

Showing result 6 - 10 of 17 swedish dissertations containing the word detritus.

2. 6. The different roles of crayfish in benthic food webs

   Author : Patrik Stenroth; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Marinbiologi; limnologi; aquatic ecology; marine biology; food chain length; stable isotopes; environmental gradients; diet; crayfish; akvatisk ekologi; limnology; Hydrobiology;

   Abstract : I show that crayfish consume detritus, algae, macrophytes, and an array of invertebrates. Crayfish were found to reduce invertebrate densities. However, prey mobility seemed to be a key factor regulating the strength of interactions between crayfish and prey. READ MORE

4. 7. The Spider and the Sea : Effects of marine subsidies on the role of spiders in terrestrial food webs

   Author : Kajsa Mellbrand; Peter Hambäck; Lena Kautsky; David Wise; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; marine subsidies; food webs; stable isotopes; shore ecosystems; predators; spiders; Pardosa; algae; emerging insects; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Plant Ecology; växtekologi;

   Abstract : The purpose of this study was to identify if terrestrial arthropod predators on Baltic Sea shores vary in their use of marine versus terrestrial food items, and to construct a bottom-up food web for Baltic Sea shores. The inflow of marine nutrients in the area consists mainly of marine algal detritus and emerging aquatic insects (e.g. READ MORE

5. 8. Solar radiation effects on decomposition and decomposers of plant litter in lakes

   Author : Måns Denward; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; glucosidase; photo inhibition; photo oxidation; littoral; lakes; ergosterol; fungi; phragmites; bacteria; UV-B; Hydrobiology; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Abstract : This thesis summarizes the results of a series of experiments, from test tube up to field study scale, performed to increase the understanding of solar radiation effects on decomposition and microbial decomposers of plant litter in stagnant water of littoral zones. In conclusion, I suggest that fungi play a significant role in the decomposition of plant litter submersed in lakes, and that their distribution is dependent on detritus quality and water chemistry, but also tends to be inversely related to the occurrence of bacteria attached to the litter. READ MORE

6. 9. Ecology across Boundaries : Food web coupling among and within ecosystems

   Author : Pia Bartels; Peter Eklöv; Lars J. Tranvik; Daniel E. Schindler; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; cross-ecosystem; food web; habitat coupling; terrestrial-aquatic linkages; subsidy; allochthonous; lake ecosystem; population divergence; trait variation; Terrestrial; freshwater and marine ecology; Terrestrisk; limnisk och marin ekologi; Freshwater ecology; Limnisk ekologi; Biology; Biologi; Biologi med inriktning mot limnologi; Biology with specialization in Limnology;

   Abstract : Cross-boundary movements of energy and material are ubiquitous. Freshwater ecosystems receive nutrients, dissolved, and particulate organic matter from adjacent terrestrial ecosystems, whereas terrestrial ecosystems mainly receive prey organisms and detritus deposited by physical processes such as floods from freshwater ecosystems. READ MORE

7. 10. 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