Search for dissertations about: "Nutrient density"

Showing result 1 - 5 of 53 swedish dissertations containing the words Nutrient density.

  2. 1. 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

  4. 2. Effects of warming and nutrient enrichment on feeding behavior, population stability and persistence of consumers and their resources

    Author : Wojciech Uszko; Sebastian Diehl; Lennart Persson; David Vasseur; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; consumer-resource; Daphnia; functional response; nutrient enrichment; parameter estimation; persistence; plankton; predator-prey; stability; temperature; type II; type III; warming;

    Abstract : Consumer-resource interactions are the basic building blocks of every food web. In spite of being a central research theme of longstanding interest in ecology, the mechanisms governing the stability and persistence of consumer-resource interactions are still not entirely understood. READ MORE

  5. 3. Algal-Bacterial Photobioreactors for the Degradation of Toxic Organic Pollutants

    Author : Raul Munoz; Bioteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bioteknik; Biotechnology; symbiosis.; nutrient removal; heavy metals removal; Algal-bacterial systems photobioreactors; toxic organic pollutants;

    Abstract : The aerobic biodegradation of toxic organic volatile contaminants is always limited by the low aqueous solubility of O2. Therefore, intensive bubbling or surface aeration is required to supply the bacterial community with sufficient O2 to carry out pollutant mineralization. This can cause the hazardous volatilization of toxic volatile contaminants. READ MORE

  6. 4. Production of Ectoines and Poly(3-Hydroxybutyrate): High Cell-Density Cultivation of Halomonas Boliviensis

    Author : Hector Guzmán; Bioteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; poly 3-hydroxybutyrate ; hydroxyectoine; ectoine; Halomonas boliviensis; compatible solutes; Fed-batch cultivation;

    Abstract : This thesis reports a study involving the use of Halomonas boliviensis, a moderate halophile, for production of biopolyester poly(3-hydroxybutyrate) (PHB) and compatible solutes ectoine and hydroxyectoine through high cell-density cultivation comprising fed-batch cultures. PHB is a biodegradable plastic produced by bacteria as energy reserve and can potentially be used as a replacement of fossil based plastic. READ MORE

  7. 5. Forest floor vegetation in Sweden : impacts of intensified forestry, nutrient addition and changes in forest structure

    Author : Per-Ola Hedwall; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Abstract : In boreal forests, dwarf-shrubs (Vaccinium spp.) often dominate the forest floor and are key-stone species in ecosystems due to their importance for nutrient cycling and as a major food source for herbivores. Forestry affects the vegetation both directly through management and indirectly by altering the forest structure. READ MORE