Sökning: "lake ecosystem"

Visar resultat 16 - 20 av 81 avhandlingar innehållade orden lake ecosystem.

1. 16. Assessing future effects on lake ecosystem resilience using data analysis and dynamic modelling : Modelling the effects of extreme weather events and climate warming on lakes

   Författare :Jorrit P. Mesman; Bastiaan W Ibelings; Stéphane Goyette; Don C Pierson; Karsten Rinke; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Extreme events; Storms; Modelling; Climate change; Thermal structure; Phytoplankton;

   Sammanfattning : Extreme weather events can have short-term and long-term effects on lake thermal structure, nutrient dynamics, and community composition. Moreover, changes in lake variables induced by global climate change may influence the response and recovery of lake ecosystems to extreme weather events. LÄS MER

3. 17. Combining limnology and paleolimnology : a refined understanding of environmental sediment signal formation in a varved lake

   Författare :Dominique Béatrice Maier; Christian Bigler; Sebastian Diehl; Jasmine E. Saros; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; varved lake sediments; diatom sediment signal formation; sequential sediment trap; seasonal process timing; ice thinning; varve compaction; climate impact; catchment properties; Earth Sciences with Specialization Environmental Analysis; geovetenskap med inriktning mot miljöanalys;

   Sammanfattning : Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. LÄS MER

4. 18. Setting the Holocene clock using varved lake sediments in Sweden

   Författare :Lovisa Zillén; Kvartärgeologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; climate change; Physical geography; tephrochronology; palaeomagnetic secular variations; radiocarbon time-scale; Holocene varved lake sediments; varve chronology; geomorphology; pedology; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi;

   Sammanfattning : The aim of this thesis was to study annually laminated (varved) Holocene lake sediment in Sweden, their formation and their potential as chronological and palaeoecological archives. Five lakes with continuous Holocene varved lake sediment sequences in northern (Västerbotten) and west central Sweden (Värmland) were investigated. LÄS MER

5. 19. Polychlorinated biphenyls (PCB) in a river ecosystem

   Författare :Gudrun Bremle; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydrobiology; dredging; landfill; cleanup; remedial action; air; fish; sediment; Persistent organic pollutants; freshwater; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi;

   Sammanfattning : Atmospheric deposition is one source of persistent pollutants such as polychlorinated biphenyls (PCB) in aquatic environments. Other point sources can also contribute to the PCB loadings in the water. LÄS MER

7. 20. Quantitative Understanding and Prediction of Lake Eutrophication

   Författare :Andreas Christoffer Bryhn; Lars Håkanson; Thorsten Blenckner; Gesa Weyhenmeyer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Freshwater ecology; Limnisk ekologi;

   Sammanfattning : Many lakes around the world have been exposed to increased nutrient input from anthropogenic sources such as sewage discharge and runoff from fertilised agricultural areas. This has led to eutrophication, manifested as intensified algal blooms, murky waters, oxygen depleted lake bottoms, and alterations of considerable parts of the foodweb. LÄS MER