Sökning: "Natural abundance of stable isotopes"

Visar resultat 1 - 5 av 21 avhandlingar innehållade orden Natural abundance of stable isotopes.

1. 1. Tracing environmental change and human impact as recorded in sediments from coastal areas of the northwestern Baltic Proper

   Författare :Lena Norbäck Ivarsson; Elinor Andrén; Thomas Andrén; Mikael Lönn; John Anderson; Södertörns högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; paleoecology; diatom stratigraphy; stable nitrogen isotopes; hypoxia; nutrient discharge; eutrophication; Medieval Climate Anomaly; Little Ice Age; Environmental Studies; Miljövetenskapliga studier; Östersjö- och Östeuropaforskning; Baltic and East European studies;

   Sammanfattning : The eutrophication of the Baltic Sea due to increased anthropogenic nutrient loads during the 20th century is well documented and studied. However, in the Baltic Sea drainage area, humans have affected the environment longer than the environmental monitoring can provide data for. LÄS MER

3. 2. Fractionation of the stable silicon isotopes : analytical method developments and selected applications in geochemistry

   Författare :Emma Engström; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

   Sammanfattning : During the last few decades, variations in the 'natural' isotopic abundances of stable elements (termed 'fractionation') have received considerable interest from the scientific community. Though analytical methods and techniques for the measurement of isotopic abundances with adequate figures of merit have been available for light elements (e.g. LÄS MER

4. 3. Studies on Baltic Sea mysids

   Författare :Martin Ogonowski; Sture Hansson; Jörgen Berge; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mysids; hydroacoustics; Baltic Sea; abundance; stable isotopes; specific dynamic action SDA ; diel vertical migration; partial migration; trophic interactions; physiology; benthic-pelagic coupling; protein:DNA; C:N ratio; genetic structure; Marine Ecology; marin ekologi;

   Sammanfattning : Mysid shrimps (Mysidacea, Crustacea) are efficient zooplanktivores in both marine and freshwater systems as well as lipid rich prey for many species of fish.  Although some efforts have been made to study the role of mysids in the Baltic Sea, very few studies have been carried out in recent time and there are still knowledge gaps regarding various aspects of mysid ecology. LÄS MER

5. 4. Species interactions in streams - effects of predation, competition and ecosystem properties

   Författare :Erika Nilsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; behaviour; species abundance; stable isotopes; habitat complexity; niche width; niche overlap; competition; streams; predation;

   Sammanfattning : Stream ecosystems are dynamic and they have an inherent environmental variability. Organisms that live in streams are adapted to the continuously changing environment and the presence or absence of species are determined by their environmental requirements, while abundance is most often affected by interactions, such as competition and predation, with other species that are found in the same habitat. LÄS MER

7. 5. Isotope-based constraints on sources and processing of black carbon, carbon monoxide, and brown carbon in South Asia

   Författare :Sanjeev Dasari; Örjan Gustafsson; August Andersson; Jos Lelieveld; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; South Asia; Air Pollution; Short-Lived Pollutants; Atmospheric Abundance; Model-Observation Mismatch; Radiocarbon; Stable Isotopes; Applied Environmental Science; tillämpad miljövetenskap;

   Sammanfattning : The highly populated South Asian region is facing rapid economic growth and urbanization. Here, both climate- and health-affecting atmospheric agents such as light-absorbing aerosols black carbon (BC) and brown carbon (BrC), trace gas carbon monoxide (CO), are often found in relatively high levels compared to in other regions. LÄS MER