Sökning: "permafrost"
Visar resultat 21 - 25 av 71 avhandlingar innehållade ordet permafrost.
21. Spatial and Temporal Variations of Solifluction and Related Environmental Parameters in the Abisko Mountains, Northern Sweden
Sammanfattning : This thesis presents an assessment of the variation in solifluction occurrence, morphometry and movement rates in the Abisko region, northern Sweden. Variations in movement rates are analyzed both on a regional and local scale. LÄS MER
22. The Torneträsk System - A basis for predicting future subarctic ecosystems
Sammanfattning : Arctic and subarctic areas have experienced a rapid warming and substantial increases in precipitation in recent decades. The frequency and intensity of some extreme events, such as fires, winter warming events, extreme rainfall, and droughts, has also increased. LÄS MER
23. Iron in the Lena River basin, NE Russia : Insights from microscopy, spectroscopy and isotope analysis
Sammanfattning : Iron is an important mediator of biotic and abiotic processes on the Earth’s surface, being an electron acceptor in organic matter degradation, a surface for organic matter and trace element adsorption, and a required element for enzymatic processes during primary production. Yet, the role of iron as a mediator of carbon and trace element cycling in high latitude, permafrost-dominated regions remains poorly investigated. LÄS MER
24. Studies of an elusive element : processes that influence the net retention of mercury in lake sediments and peatlands
Sammanfattning : Because of its toxic nature mercury is a threat to both wildlife and human health, and thus, it is an element of concern in the environment. Currently much of the mercury emitted to the atmosphere is derived from anthropogenic sources – both direct emissions and re-emission of already deposited anthropogenic mercury. LÄS MER
25. Karaktäristiken hos strukturmarken på olika altitud i Abiskoområdet – en koppling till klimat och komplex systemteori
Sammanfattning : Subarctic and alpine areas are sensitive to climatic change when they lie at the margin of permafrost occurrence. Patterned ground in such areas is generated from an interplay among different mechanisms such as temperature, hydrology, soil texture, snow cower and vegetation. LÄS MER