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Visar resultat 21 - 25 av 251 avhandlingar som matchar ovanstående sökkriterier.

1. 21. Perturbance and Stimulation : using Nitrogen Addition and High-Throughput Sequencing to Study Fungal Communities in Boreal Forests

   Författare :Andreas N. Schneider; Nathaniel Street; Vaughan Hurry; Torgny Näsholm; Colin Averill; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Boreal forest; Scots pine; Norway spruce; ectomycorrhiza; saprotroph; fertilization; nitrogen; mycobiome; rhizosphere; decomposition; carbon; seedling establishment; forest management; clearcutting;

   Sammanfattning : Fungal communities are major players in globally important nutrient cycling processes, and form symbioses with most terrestrial plants. In the nitrogen (N) limited Swedish boreal forest, ectomycorrhizal (EcM) fungi colonize most roots of the economically important and stand dominating conifer species, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), with significant implications for tree nutrition and decomposition processes. LÄS MER

3. 22. Estimation of Forest Biomass and Faraday Rotation Using Polarimetric L-/P-band SAR

   Författare :Gustaf Sandberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; linear regression; Remote sensing; forest biomass retrieval; P-band; synthetic aperture radar SAR ; calibration; L-band;

   Sammanfattning : At present the greatest source of uncertainty in the global carbon cycle is in the terrestrialecosystems. In order to reduce these uncertainties it is necessary to provide consistent andaccurate global estimates of the biomass contained in the forests of the world. LÄS MER

4. 23. DYNAMIC MODELLING OF BIOGEOCHEMICAL PROCESSES IN FOREST ECOSYSTEMS

   Författare :Salim Belyazid; Avdelningen för kemiteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Naturvetenskap; marklära; Silviculture; forestry; forestry technology; Skogsvetenskap; skogsbruk; skogsteknik; Natural science; Lantbrukshydrologi; Soil Science; agricultural hydrology; Växtekologi; Forest Soil Acidification; Plant ecology; Plant biochemistry; Forest Growth; Vegetation biodiversity; Carbon Sequestration; Nitrogen Leaching; Miljökemi; Dynamic Modelling; Växtbiokemi; Environmental chemistry;

   Sammanfattning : Forests in Sweden are undergoing rapid and considerable changes regarding both management methods and environmental conditions. To understand the effects of these changes and to be able to predict impending changes in forest ecosystems, a holistic understanding of the processes governing the ecosystem is needed. LÄS MER

5. 24. Soil moisture conditions control nutrient accumulation, carbon storage and tree growth in boreal forest landscapes

   Författare :Johannes Larson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Forest and soil properties change across landscapes due to the complex interactions between various environmental factors. In many landscapes, topography exerts a major influence on the variation in soil moisture conditions, which in turn largely affects soil properties and processes. LÄS MER

7. 25. Carbon exchange in boreal ecosystems: upscaling and the impacts of natural disturbances

   Författare :Julia Kelly; BECC: Biodiversity and Ecosystem services in a Changing Climate; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Carbon fluxes; CH4; Climate change; CO2; Drought; Ecosystem respiration; Forest; Peatland; Remote sensing; Temperature; Thermal camera; UAV; Wildfire;

   Sammanfattning : Boreal forests and peatlands are globally significant carbon stores but they are threatened by rising air temperatures and changes in precipitation regimes and the frequency of natural disturbances. Predicting how the boreal biome will respond to climate change depends on being able to accurately model and upscale the greenhouse gas fluxes between these ecosystems and the atmosphere. LÄS MER