Sökning: "tree crown"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden tree crown.

  1. 1. Evolution of Plants : a mathematical perspective

    Författare :Magnus Lindh; Åke Brännström; Jacob Johansson; Mats G Larson; Lennart Persson; Claus Rüffler; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Evolution; plants; mathematics; optimization; optimal control; adaptive dynamics; flowering; seasons; tree crown; drought; taproot; trade-off; strategy; trait; ESS; NPP; LAI; Red Queen; Mathematics; matematik;

    Sammanfattning : The Earth harbors around 300 000 plant species. The rich and complex environment provided by plants is considered a key factor for the extraordinary diversity of the terrestrial fauna by, for example, providing food and shelter. LÄS MER

  2. 2. Individual-tree-selection in uneven-sized Norway spruce stands in southern Sweden : Developments of tools for simulation and optimization

    Författare :Nils Fagerberg; Johan Bergh; Peter Lohmander; Stergios Adamopoulos; Hubert Hasenauer; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; continuous cover forestry; selective cutting; Picea abies; uneven-aged; single-tree-selection; growth model; knot size model; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Individual-tree-selection (ITS) is a continuous cover forestry method that aims to utilize the uneven-sized stand structure through optimized individual tree selections. ITS is an interesting management alternative to rotation forestry in terms of production of multiple benefits and forest owner profitability. LÄS MER

  3. 3. Optimal thinning : a theoretical investigation on individual-tree level

    Författare :Peter Fransson; Åke Brännström; Ola Lindroos; Oskar Franklin; Per Lundberg; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Forest management; Simulation; Optimization; Spatially explicit model; Individual-based model;

    Sammanfattning : Paper I: In paper I, we asked how a tree should optimally allocate its resources to maximize its fitness. We let a subject tree grow in an environment shaded by nearby competing trees. The competitors were assumed to have reached maturity and had stopped growing, thus creating a static light environment for the subject tree to grow in. LÄS MER

  4. 4. Reproductive Biology and Population Genetics of Common Ash (Fraxinus excelsior L.)

    Författare :Grazyna Bochenek; Göteborgs universitet; []
    Nyckelord :Fraxinus excelsior; delayed fertilization; functional dioecy; gender-related grow difference; inbreeding; tree-rings; non random mating; wind-pollination;

    Sammanfattning : Common Ash, Fraxinus excelsior L. (Oleaceae) is a wind-pollinated, wind-dispersed, deciduous tree, commonly occurring throughout Central and Northern Europe. The thesis addresses several questions concerning reproductive biology and factors influencing the genetic richness of ash stands. LÄS MER

  5. 5. Tree Species Classification : Analyzing Multitemporal Satellite Imagery and Multispectral Airborne Laser Scanning Data

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

    Sammanfattning : Tree species composition of forests affects the whole ecosystem and is part of the information needed for an efficient planning of forest management. This thesis explores how recent developments in remote sensing can provide more accurate tree species mapping. LÄS MER