Sökning: "soil heterogeneity"

Visar resultat 16 - 20 av 38 avhandlingar innehållade orden soil heterogeneity.

  1. 16. Regional and local variation in plant species richness

    Författare :Cecilia Dupré; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; coastal meadows; deciduous forests; dry grasslands; grazing; habitat configuration; habitat quality; hump-shaped curve; life history traits; regional species pool; soil factors; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : In this thesis, I examine the variation in plant species richness along gradients of productivity and disturbance in grasslands and forest habitats in southern Sweden, and I compare the documented patterns with theoretical predictions. Moreover, I evaluate the relative importance of habitat quality and habitat configuration for the occurrence of field layer species in deciduous forests. LÄS MER

  2. 17. Processes controlling carbon fluxes in the soil-vegetation-atmosphere system

    Författare :David Hadden; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Increasing emissions of carbon dioxide (CO2) to the atmosphere have a direct impact on global warming and climate change. The ability of ecosystems to sequester CO2 is therefore of great importance. The Boreal forest contains one of the world’s largest carbon stocks after having acted as a net sink of CO2 for thousands of years. LÄS MER

  3. 18. Network Modelling for Evaluation of Mechanical Properties of Cellulose Fibre Fluff

    Författare :Susanne Heyden; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulic engineering; Civil engineering; fracture; fibres; computer simulation; offshore technology; soil mechanics; Väg- och vattenbyggnadsteknik;

    Sammanfattning : A network mechanics model for cellulose fibre fluff is proposed. 2D and 3D versions of the model have been implemented and the influence of various micro-level parameters on the global mechanical performance has been determined by means of computer simulations. LÄS MER

  4. 19. Theoretical Investigation into Longitudinal Dispersion in Natural Rivers — A Scaling Dispersion Model

    Författare :Zhi-Qiang Deng; Avdelningen för Teknisk vattenresurslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; soil mechanics; Väg- och vattenbyggnadsteknik; Environmental technology; pollution control; Miljöteknik; kontroll av utsläpp; offshore technology; hydraulic engineering; Civil engineering; Scaling dispersion.; Parameter estimation; Numerical scheme; Dispersion coefficient; Natural river;

    Sammanfattning : Using a broad variety of scientific methods this dissertation systematically investigates the fundamental mechanisms underlying the dispersion processes in natural rivers and their mathematical descriptions in a geometrical framework. Emphasis is on the geometrical variations and irregularities of a natural river and their scales. LÄS MER

  5. 20. Free mica in crushed rock aggregates

    Författare :Eva Johansson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geoteknik; Soil Mechanics;

    Sammanfattning : Free mica particles in crushed rock aggregates for constructional purposes affect the quality of the end product. It is also known that mica-bearing rocks may cause damages of the road constructions, especially in regions with a temperate climate. The negative influence arises in both bounded and unbounded layers. LÄS MER