Sökning: "vertical migration"

Visar resultat 1 - 5 av 31 avhandlingar innehållade orden vertical migration.

1. 1. Diel vertical migration in marine dinoflagellates

   Författare :Therese Jephson; Enhet akvatisk ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Key words: diel vertical migration; DVM; dinoflagellates; stratification; halocline; thermocline; behavior diel vertical migration; behavior;

   Sammanfattning : Increasing precipitation and surface water temperature due to global change may strengthen stratification in coastal regions, which could influence the behavior of dinoflagellate diel vertical migration (DVM). DVM is a behavioral mechanism by which dinoflagellates can access photosynthetically active radiation near the surface, and nutrients at depth. LÄS MER

3. 2. Studies on Baltic Sea mysids

   Författare :Martin Ogonowski; Sture Hansson; Jörgen Berge; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mysids; hydroacoustics; Baltic Sea; abundance; stable isotopes; specific dynamic action SDA ; diel vertical migration; partial migration; trophic interactions; physiology; benthic-pelagic coupling; protein:DNA; C:N ratio; genetic structure; Marine Ecology; marin ekologi;

   Sammanfattning : Mysid shrimps (Mysidacea, Crustacea) are efficient zooplanktivores in both marine and freshwater systems as well as lipid rich prey for many species of fish.  Although some efforts have been made to study the role of mysids in the Baltic Sea, very few studies have been carried out in recent time and there are still knowledge gaps regarding various aspects of mysid ecology. LÄS MER

4. 3. Filamentous cyanobacteria in the Baltic Sea - spatiotemporal patterns and nitrogen fixation

   Författare :Lisa Almesjö; Ragnar Elmgren; Norbert Wasmund; Stockholms universitet; []
   Nyckelord :Aphanizomenon sp.; Nodularia spumigena; Baltic Sea; image analysis; spatial variability; nitrogen fixation; vertical migration; marin ekologi; Marine Ecology;

   Sammanfattning : Summer blooms of filamentous, diazotrophic cyanobacteria are typical of the Baltic Sea Proper, and are dominated by Aphanizomenon sp. and the toxic Nodularia spumigena. Although occurring every summer, the blooms vary greatly in timing and spatial distribution, making monitoring difficult and imprecise. LÄS MER

5. 4. Studies on the Gamma Radiation Environment in Sweden with Special Reference to 137Cs

   Författare :Sara Almgren; Göteborgs universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; gamma radiation; caesium; 137Cs; deposition; migration; precipitation; in situ; CDE; NWF; Chernobyl; soil sampling; field measurements; dose measurements; dose rate; TLD; natural radiation; Kriging;

   Sammanfattning : Gamma radiation in the environment today mainly originates from naturally occurring radionuclides, but anthropogenic radionuclides, such as 137Cs, contribute in some areas. In order to assess population exposure in case of fallout from nuclear weapons (NWF) or accidents, knowledge and monitoring of external gamma radiation and radionuclide concentrations in the environment is important. LÄS MER

7. 5. Intraspecific diversity of pike (Esox lucius) in the Baltic Sea and new insights on thermoregulation in fish

   Författare :Oscar Nordahl; Per Larsson; Anders Forsman; Juha Merilä; Linnéuniversitetet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; adaptive divergence; Cyprinus carpio; ecology; Esox lucius; evolution; local adaptation; management; thermoregulation; sun-basking; vertical migration; Akvatisk ekologi; Aquatic Ecology; Evolutionary Biology; Evolutionsbiologi;

   Sammanfattning : Fish display a fascinating variation in behavior, morphology and physiology among species, among individuals within species, and within individuals over time. A central quest in ecology and evolution is to understand causes and consequences of such variation. LÄS MER