Sökning: "mesocosm"

Visar resultat 1 - 5 av 41 avhandlingar innehållade ordet mesocosm.

1. 1. Ecotoxicological assessment by microcosm tests on plankton communities

   Författare :Pardis Pirzadeh; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; limnologi; Marinbiologi; aquatic ecology; limnology; Ecology; Ekologi; Hydrobiology; marine biology; musk substances; brominated flame retardants; structural effects; akvatisk ekologi; Environmental chemistry; Miljökemi; mesocosm;

   Sammanfattning : The aim of this thesis is to present a short-term plankton community toxicity test in laboratory microcosms, with which the effect of the test substance on species abundance and composition of the community is evaluated. This laboratory microcosm is an intermediate between single-species tests and outdoor mesocosm tests. LÄS MER

3. 2. Response of marine food webs to climate-induced changes in temperature and inflow of allochthonous organic matter

   Författare :Rickard Degerman; Agneta Andersson; Risto Lignell; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Climate change; bacterial production; mesocosm; food web efficiency; Baltic Sea;

   Sammanfattning : Global records of temperature show a warming trend both in the atmosphere and in the oceans. Current climate change scenarios indicate that global temperature will continue to increase in the future. The effects will however be very different in different geographic regions. LÄS MER

4. 3. Carbon Dioxide in Inland Waters : Drivers and Mechanisms Across Spatial and Temporal Scales

   Författare :Anna Cecilia Nydahl; Gesa A. Weyhenmeyer; Marguerite Xenopoulos; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbon dioxide; dissolved organic carbon; inland water; lake; stream; groundwater; mesocosm; carbonate system; carbon; Biology with specialization in Limnology; Biologi med inriktning mot limnologi;

   Sammanfattning : Inland waters are an essential component of the global carbon cycle as they are very active sites for carbon transformation processes. Much of this carbon is transformed into the greenhouse gas carbon dioxide (CO2) and emitted into the atmosphere. LÄS MER

5. 4. Transformation of Micropollutants in the Hyporheic Zone

   Författare :Malte Posselt; Jonathan P. Benskin; Michael Radke; Merle Plassmann; Magnus Breitholtz; Ian Cousins; Gudrun Massmann; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; micropollutants; hyporheic zone; biodegradation; bacteria; pharmaceuticals; transformation products; LC-MS MS; macrophytes; bedforms; suspect screening; mesocosm; flume; river; Applied Environmental Science; tillämpad miljövetenskap;

   Sammanfattning : Hyporheic zones (HZs) are reactive transition regions between rivers and aquifers which are thought to play an important role in the attenuation of micropollutants. Micropollutants are chemical substances such as pharmaceuticals, industrial chemicals or personal care products that are found in trace concentrations in the environment and that can be harmful to organisms. LÄS MER

7. 5. Pigment and Thiamine Dynamics in Marine Phytoplankton and Copepods

   Författare :Ingrid Wänstrand; Pauli Snoeijs; Marianne Pedersén; Helmut Hillebrandt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; phytoplankton composition; pigments; chemotaxonomy; inorganic nutrients; pelagic copepods; grazing; astaxanthin; thiamine; mesocosm experiments; marine food webs; eutrophication; Baltic Sea; Biologi; Biology; Biologi;

   Sammanfattning : Based on a field study and several mesocosm experiments, I evaluated the use of pigments as chemotaxonomical biomarkers for phytoplankton community composition in the Baltic Sea and I examined effects of inorganic nutrients on the dynamics of carotenoids and thiamine (vitamin B1) at the phytoplankton–copepod level in marine pelagic food webs. My results show that HPLC pigment analysis combined with CHEMTAX data processing was an accurate alternative to microscopic analysis of Baltic Sea phytoplankton. LÄS MER