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Showing result 1 - 5 of 11 swedish dissertations matching the above criteria.

  2. 1. Effects of heavy metal contamination on carbon and nitrogen cycling : An ecological approach to assess risks to soil functions

    Author : Ingrid Rijk; Alf Ekblad; Dan Berggren Kleja; Erik Karltun; Örebro universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; heavy metals; soil contamination; stable isotopes; N cycling microbial guilds; 13C; 15N; nitrification; denitrification; biochar; soil respiration; microbial activity; bioavailability;

    Abstract : Soil contamination with heavy metals may disrupt soil microorganisms with important roles in carbon (C) and nitrogen (N) cycling. However, there is a lack of understanding on how microorganisms are affected in soil, which may lead to a mismatch when assessing risks of contaminants to field soils. READ MORE

  4. 2. The effect of protein intake and physical exercise on energy turnover and substrate utilisation at energy balance in man

    Author : Anders H. Forslund; Uppsala universitet; []
    Keywords : Medical sciences; Body composition; carbohydrate; energy turnover; fat; protein; stable isotopes; MEDICIN OCH VÅRD; MEDICINE; MEDICIN; Nutrition; näringslära;

    Abstract : The principal goal of the thesis has been to evaluate the effect of protein intake and physical exercise on energy turnover and substrate utilisation. Body composition assessment is of importance as an indicator of the energy balance. Therefore, in the first study the aim was to develop new models to estimate body composition more accurately. READ MORE

  5. 3. Living in a predation matrix : Studies on fish and their prey in a Baltic Sea coastal area

    Author : Ida Ahlbeck; Sture Hansson; Hannu Lehtonen; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; diet analysis methods; Sander lucioperca; behaviour; rearing environment; diel vertical migration; Acartia spp.; Eurytemora affinis; Perca fluviatilis; stable isotopes; body condition; sedentarity; Marine Ecology; marin ekologi;

    Abstract : This thesis was written within the framework of a biomanipulation project where young-of-the-year (YOY) pikeperch (Sander lucioperca) were stocked to a Baltic Sea bay to improve water quality through a top-down trophic cascade. The aim of my doctorial studies was however focused on a broader ecological question, namely predation (the main driving force in a biomanipulation). READ MORE

  6. 4. Herbivores influence nutrient cycling and plant nutrient uptake : insights from tundra ecosystems

    Author : Hélène Barthelemy; Olofsson Johan; Ellen Dorrepaal; Ann Milbau; Gough Laura; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Reindeer grazing; large herbivores; nutrient cycling; plant nutrient uptake; soil nutrient availability; arctic plant ecology; soil microbial communities; 15N stable isotopes; plant-soil interactions; plant quality; dung and urine.; Environmental Science; miljövetenskap; biology; biologi;

    Abstract : Reindeer appear to have strong positive effects on plant productivity and nutrient cycling in strongly nutrient-limited ecosystems. While the direct effects of grazing on vegetation composition have been intensively studied, much less is known about the indirect effect of grazing on plant-soil interactions. READ MORE

  7. 5. The Threat to the Baltic Salmon - a Combination of Persistent Pollutants, Parasite and Oxidative Stress

    Author : Maria Persson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Salmo salar; Atlantic salmon; polychlorinated biphenyls; Animal ecology; akvatisk ekologi; limnologi; Marinbiologi; limnology; aquatic ecology; marine biology; Hydrobiology; Ekologi; Ecology; lake Vänern; lake Vättern; Baltic Sea; Eubothrium crassum; aryl hydrocarbon receptor; AHR; consumption advice; stable isotopes; astaxanthin; EROD; M74; antioxidants; biomagnification; cestodes; parasites; DDT; Djurekologi; Environmental chemistry; Miljökemi; PCB;

    Abstract : Atlantic salmon (Salmo salar) from the Baltic Sea suffer from a reproduction disease known as the M74-syndrome. Newly hatched fry develop nerve disorders and die between 3-5 days after the first symptoms are seen. This is a maternally transmitted disease that is casued by a thiamine (vitamin B1) deficiency. READ MORE