Sökning: "fish population"

Visar resultat 1 - 5 av 189 avhandlingar innehållade orden fish population.

  1. 1. MULTIFOCAL SPHERICAL FISH LENSES

    Författare :Yakir Gagnon; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Multifocal Lens; Adaptation; Dispersion; Spherical lens; Model; Fish; Ray-trace; Longitudinal Chromatic Aberration; Longitudinal Spherical Aberration; Modulation Transfer Function; Point Spread Function; Refractive Index Gradient;

    Sammanfattning : Vision is an important source of information for many animals. The lens plays a central role in the visual pathway and hence the ecology of these animals. Fish have spherically shaped crystalline lenses that contain a gradient of refractive index. Like all refracting elements, lens performance depends on the wavelength of the refracted light. LÄS MER

  3. 2. Endocrine disruption in fish : Effects of 17α-ethinylestradiol exposure on non-reproductive behavior, fertility and brain and testis transcriptome

    Författare :Tove Porseryd; Inger Porsch Hällström; Ioanna Katsiadaki; Södertörns högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 17α-ethinylestradiol; endocrine disrupting chemical; fish; behavior; fertility; transcriptome; RNA sequencing; Environmental Studies; Miljövetenskapliga studier; Östersjö- och Östeuropaforskning; Baltic and East European studies;

    Sammanfattning : Aquatic environments are the end recipient for most anthropogenic chemical pollutants. One common chemical pollutant found in the aquatic environment is 17α-ethinylestradiol (EE2), a synthetic estrogen used in contraceptive pills. LÄS MER

  4. 3. Offshore wind farms - ecological effects of noise and habitat alteration on fish

    Författare :Mathias H. Andersson; Sören Nylin; Magnus Wahlberg; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; renewable energy; fish population; artificial reef; attraction vs. production; habitat structure; reef effect; FAD; bioacoustics; noise disturbance; fish behaviour; detection range; threshold; masking; fish communication and hearing; Marine ecology; Marin ekologi; zoologisk ekologi; Animal Ecology;

    Sammanfattning : There are large gaps in our understanding how fish populations are affected by the anthropogenic noise and the alteration of habitat caused by the construction and operation of offshore wind farms. These issues are of great importance as the construction of offshore wind farms will increase all over the world in the near future. LÄS MER

  5. 4. Crossing barriers: Genetic consequences of translocating wild cleaner fish for aquaculture

    Författare :Ellika Faust; Göteborgs universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; conservation genetics; population genetics; aquaculture escapee; hybridisation; corkwing wrasse; lumpfish; cleaner fish translocation; sea lice; range expansion; fishery management;

    Sammanfattning : Several species of fish show a symbiotic cleaning behaviour, where they assist other species by feeding and removing dead skin or ectoparasites. Some of these cleaner fish species are used as a low-cost parasite control in salmon aquaculture, often considered to be more environmentally friendly than other delousing methods. LÄS MER

  7. 5. Biofilms in Nitrogen Removal - Bacterial Population Dynamics and Spatial Distribution

    Författare :Robert Almstrand; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; AOB; NOB; biofilms; image analysis; FISH; Nitrosomonas; population dynamics; spatial distribution;

    Sammanfattning : Efficient nitrogen removal at wastewater treatment plants (WWTPs) is necessary to avoid eutrophication of recipient waters. The most commonly used approach consists of aerobic nitrification and subsequent anaerobic denitrification resulting in the release of dinitrogen gas into the atmosphere. LÄS MER