Sökning: "environmental gradient"

Visar resultat 1 - 5 av 168 avhandlingar innehållade orden environmental gradient.

  1. 1. Biomarkers in perch (Perca fluviatilis) used in environmental monitoring of the Stockholm recipient and background areas in the Baltic Sea

    Detta är en avhandling från Stockholm : Institutionen för tillämpad miljövetenskap (ITM)

    Författare :Tomas Hansson; Lennart Balk; Ulf Rannug; Tracy Collier; ; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biomarker; DDT; environmental monitoring; EROD; fish; GSI; nanoinjection; PAH; PCB; Perca fluviatilis; perch; reproduction; NATURAL SCIENCES Chemistry Environmental chemistry Environmental toxicology; NATURVETENSKAP Kemi Miljökemi Miljötoxikologi; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : This thesis reports the results of biomarker measurements in three environmental monitoring projects. In the first project, which was part of the Swedish national environmental monitoring, biomarkers were measured annually in female perch (Perca fluviatilis) in two background areas in the Baltic Sea during 1988–2000, resulting in a unique 13-year series of measurements. LÄS MER

  3. 2. Properties and analysis of dioxin-like compounds in marine samples from Sweden

    Detta är en avhandling från Umeå : Kemi

    Författare :Kjell Lundgren; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; planar dioxin-like compound; polychlorinated dibenzofuran; polychlorinated biphenyl; polychlorinated naphthalene; alkylated polychlorinated dibenzofuran; high-performance liquid chromatography; PX-21 carbon column; biomagnification factor; biota to sediment accumulation factor; fluxes; relative retention time; mass spectrometry; relative response factor; ultra-violet spectroscopy; Miljökemi; NATURAL SCIENCES Chemistry Environmental chemistry; NATURVETENSKAP Kemi Miljökemi; analytisk kemi; Analytical Chemistry;

    Sammanfattning : Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) have been assigned toxic equivalency factors (TEFs). These compounds are today routinely analysed with sophisticated analytical techniques. LÄS MER

  4. 3. Soil salinity as a driver of microbial community structure and functioning

    Detta är en avhandling från Lund University, Faculty of Science, Centre for Environmental and Climate Research (CEC)

    Författare :Kristin Rath; [2017-12]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Soil salinization; Soil Microbiology; soil microbial community; Bacteria; Aerobic; Fungi; Drying-rewetting; Microbial growth; Microbial biomass; Soil respiration; salinity tolerance; Saline soils; Salinity gradient;

    Sammanfattning : Soil salinization is a pressing agricultural problem in many areas of the world, particularly in areas heavily reliant on irrigation agriculture. While the negative effects of salinity on crop plants have been widely studied, its effects on soil microorganisms have received less attention, and the impact of soil salinity on both microbial community structure and functioning is not well understood. LÄS MER

  5. 4. Ecology of zooplankton communities: climate, dormancy, and benthic-pelagic coupling

    Detta är en avhandling från Mikael Gyllström, Limnology, Ecology Building, S-223 62, Lund, Sweden

    Författare :Mikael Gyllström; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Marinbiologi; limnologi; akvatisk ekologi; limnology; Hydrobiology; marine biology; aquatic ecology; phytoplankton; temporal stability; recruitment; seasonal succession; environmental cues; diapause; shallow lakes; predation; enrichment; climate; temperature;

    Sammanfattning : This thesis describes how influences, such as top down and bottom up forces, shape zooplankton communities in shallow lakes. I have also extended the traditional food-web theory by investigating the effects of climate on total biomass, taxonomic composition, and temporal properties of zooplankton communities. LÄS MER

  7. 5. Mixture Effects of Environmental Contaminants

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Erik Lampa; Monica Lind; Jonas Björk; [2015]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mixtures; Environmental Contaminants; Atherosclerosis; Metabolic Syndrome; Boosting; Epidemiology;

    Sammanfattning : Chemical exposure in humans rarely consists of a single chemical. The everyday exposure is characterized by thousands of chemicals mainly present at low levels. Despite that fact, risk assessment of chemicals is carried out on a chemical-by-chemical basis although there is a consensus that this view is too simplistic. LÄS MER