Sökning: "perca-fluviatilis"

Visar resultat 21 - 25 av 44 avhandlingar innehållade ordet perca-fluviatilis.

1. 21. Development of GC-HRMS procedures for determination of naturally occuring polar compounds in various environmental applications

   Författare :Bodil Widell; Dag Broman; Caroline Leck; Joan Grimalt; Stockholms universitet; []
   Nyckelord :GC-HRMS; steroid hormones; amino acids; perch; size-resolved aerosol; Arctic; NATURAL SCIENCES; NATURVETENSKAP; Applied Environmental Science; tillämpad miljövetenskap;

   Sammanfattning : The overall objectives of this dissertation were to gain further understanding of the two following environmentally significant issues: (i) Determination of natural steroid hormones in blood plasma from perch (Perca fluviatilis) during a reproductive cycle and to evaluate the possibility of using the steroid composition as a biomarker for early signs of endocrine disruptive effects. (ii) Determination of dissolved free amino acids in size resolved airborne particles collected over the Arctic pack ice area (>80°N) in summer and to study their overall relationship with the ocean surface microlayer as a potential source. LÄS MER

3. 22. Habitat use in fish communities : size- and environment-dependent mechanisms affecting biotic interactions and population regulation

   Författare :Ulrika Beier; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Through the influence of abiotic factors, the habitat use of organisms affects their metabolism as well as other species- and size-dependent individual-based rates. The habitat-specific performances of individuals interacting in different habitats thereby affect biotic interactions. LÄS MER

4. 23. Influence of cyanobacterial blooms on coastal fish recruitment

   Författare :Karl-Johan Persson; Catherine Legrand; Markku Viitasalo; Linnéuniversitetet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cyanobacteria; coastal fish recruitment; Akvatisk ekologi; Aquatic Ecology;

   Sammanfattning : Cyanobacteria are the oldest oxygen-producing organisms on Earth and can be found in almost every terrestrial and aquatic habitat. Their long evolutionary history has enabled them to develop diverse adaptations in order to increase their survival in environments subjected to natural and anthropogenic changes. LÄS MER

5. 24. Warmer and browner waters: fish responses vary with size, sex, and species

   Författare :Renee Van Dorst; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Current understanding of fish population responses to climate change is often limited to studies on the effect of temperature, ignoring potential co-occurring changes in other environmental variables. However, next to getting warmer, temperate and boreal aquatic systems are getting browner due to increased concentrations of dissolved organic carbon. LÄS MER

7. 25. Fungal and mussel protein sources in fish feed : nutritional and physiological aspects

   Författare :Aleksandar Vidakovic; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

   Sammanfattning : Fungal and mussel protein sources in the diet of Eurasian perch (Perca fluviatilis), Arctic charr (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss) and their effect on growth performance, nutrient utilisation, intestinal barrier function and post-prandial profiles of plasma amino acids and whole blood parameters were evaluated in this thesis. Apparent digestibility of dry matter, sum of amino acids and gross energy in experiment with Arctic charr decreased with dietary inclusion of intact Saccharomyces cerevisiae. LÄS MER