Sökning: "freshwater fish"

Visar resultat 1 - 5 av 85 avhandlingar innehållade orden freshwater fish.

1. 1. Biotic resistance in freshwater fish communities

   Författare :Anna Henriksson; Göran Englund; David Wardle A.; Jun Yu; Sebastian Diehl; Donald Jackson; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biotic resistance; freshwater fish; introductions; invasions; invasion success; invasibility; invasiveness; species richness; saturation; species identity; weighted species richness;

   Sammanfattning : Invasions of non-native species cause problems in ecosystems worldwide, and despite the extensive effort that has been put into research about invasions, we still lack a good understanding for why some, but not other, communities resist these invasions. In this doctoral thesis I test hypotheses on biotic resistance using a large dataset of more than 1000 both failed and successful introductions of freshwater fish into Swedish lakes. LÄS MER

3. 2. Assembly of Gut Microbial Communities in Freshwater Fish and Their Roles in Fish Condition

   Författare :Yinghua Zha; Richard Svanbäck; Eva Lindström; Peter Eklöv; Brendan Bohannan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; freshwater fish; gut microbial communities; predation stress; diet; fish condition; bacterial colonization; metacommunity theory; dispersal; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

   Sammanfattning : Animal hosts provide associated microorganisms with suitable ecological niches in their intestines. Microbes help their hosts to digest food, protect against pathogens, and influence the host’s metabolisms. Compositional variation of gut microbial communities is common among hosts, and may affect the health status of hosts. LÄS MER

4. 3. Spatial Modelling of Coastal Fish – Methods and Applications

   Författare :Göran Sundblad; Ulf Bergström; Alfred Sandström; Peter Eklöv; Christian Möllmann; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; habitat; niche; species distribution modelling; juvenile; fish; larvae; spawning; Marine ecology; Marin ekologi; NATURAL SCIENCES; NATURVETENSKAP; Freshwater ecology; Limnisk ekologi; Biology; Biologi; Biology with specialization in Limnology; Biologi med inriktning mot limnologi; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology; Limnologi; Limnology;

   Sammanfattning : Environmental factors influence species and habitats on multiple scales creating a mosaic of distribution patterns. Studying factors shaping these patterns are central to our understanding of population dynamics and ultimately ecosystem functioning. LÄS MER

5. 4. Polychlorinated biphenyls (PCB) in a river ecosystem

   Författare :Gudrun Bremle; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; dredging; landfill; cleanup; remedial action; air; fish; sediment; Persistent organic pollutants; freshwater; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : Atmospheric deposition is one source of persistent pollutants such as polychlorinated biphenyls (PCB) in aquatic environments. Other point sources can also contribute to the PCB loadings in the water. LÄS MER

7. 5. Estrogen receptor and multixenobiotic resistance genes in freshwater fish and snails: identification and expression analysis after pharmaceutical exposure

   Författare :Cecilia Hultin; Miljövetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; EE2; NSAID; estrogen receptor; oestrogen receptor; multixenobiotic resistance; fish; gastropods;

   Sammanfattning : Pharmaceuticals are today released into aquatic environments where they can interfere with organisms' biological processes.The general research objective was to analyze how aquatic freshwater organisms are affected by exposure to pharmaceuticals that are categorized by the EU as potential risk factors to the environment (i.e. LÄS MER