Sökning: "soil physical characteristics"

Visar resultat 1 - 5 av 40 avhandlingar innehållade orden soil physical characteristics.

1. 1. Permafrost carbon in a changing Arctic : On periglacial landscape dynamics, organic matter characteristics, and the stability of a globally significant carbon pool

   Författare :Niels Weiss; Peter Kuhry; Duane Froese; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Permafrost; Carbon; Climate; Arctic; Soil; Organic Matter; Cryosphere; Geomorphology; Physical Geography; naturgeografi;

   Sammanfattning : Organic matter (OM) in arctic permafrost ground contains about twice as much carbon (C) as is currently present in the atmosphere. Climate change is particularly strong in the Arctic, and could cause a considerable part of the OM in permafrost to thaw out, decompose, and be released as greenhouse gases; further enhancing global warming. LÄS MER

3. 2. Seasonal variation and landscape regulation of dissolved organic carbon concentrations and character in Swedish boreal streams

   Författare :Anneli Ågren; Mats Jansson; Irena Creed; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DOC; temporal variation; spatial variation; seasonal variation; forested catchment; wetland catchment; catchment characteristics; DOC characteristics; absorbance-ratio; bioavailability.; Physical geography; Naturgeografi;

   Sammanfattning : The seasonal variation and landscape regulation of dissolved organic carbon (DOC) concentrations in streams have been studied in two watersheds in the boreal zone. The seasonal variation was found to be highly correlated to variations in runoff. An increase in runoff was always accompanied with an increase in DOC concentration. LÄS MER

4. 3. Relations between soil organic carbon, soil structure and physical processes in an agricultural topsoil : The role of soil mineral constituents

   Författare :Jumpei Fukumasu; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

   Sammanfattning : A better understanding of the interactions between soil organic carbon (SOC) and mineral constituents (e.g. clay and reactive oxide phases) and their consequences for soil structure and physical processes is important for assessing the potential for, and benefits of, carbon sequestration in arable soils. LÄS MER

5. 4. Landslide scars in the Kenyan highlands : Physical and chemical topsoil changes and landslide susceptibility assessment under tropical conditions

   Författare :Anna Wahlstrand; Ingmar Borgström; Lars-Ove Westerberg; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical Geography; naturgeografi;

   Sammanfattning : Farmers living in the Kenyan highlands are exposed to the risk of being affected by landslides and they are vulnerable because of lack of resources. Vulnerability can be reduced by increasing knowledge and awareness of the risk. This thesis aims to increase knowledge of landslide-related problems. LÄS MER

7. 5. Trees and the environment : Possibilities and challenges in tree-ring research across spatial and temporal scales based on case studies in Sweden

   Författare :Eva Rocha; Steffen Holzkämper; Björn Gunnarson; Anders Moberg; Martin De Luis; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tree rings; Sweden; climate variability; environmental monitoring; ring width; maximum latewood density; stem radial increment; ED-XRF; light rings; Physical Geography; naturgeografi;

   Sammanfattning : The need to understand and quantify the magnitude and frequency of past and current environmental changes increased the demand for high-resolution proxy data across spatial and temporal scales. Due to their long lifespan and global distribution, trees provide a unique and continuous record of environmental variability. LÄS MER