Sökning: "Species tree"
Visar resultat 16 - 20 av 314 avhandlingar innehållade orden Species tree.
16. Pressurised Fluid Extraction of Bioactive Species in Tree Barks : Analysis using Hyphenated Electrochemical Mass Spectrometric Detection
Sammanfattning : Analytical chemistry has developed throughout time to meet current needs. At present, the interest in biorefinery is growing, due to environmental awareness and the depletion of fossil resources. Biomass from agricultural and forestry industries has proven to be excellent raw material for different processes. LÄS MER
17. Multi-trait Branching Models with Applications to Species Evolution
Sammanfattning : This thesis provides an analysis of the evolution of discrete traits and their effect on the birth and survival of species using the theory of supercritical, continuous time Markov branching processes. We present a branching modeling framework that incorporates multi-trait diversification processes associated with the emergence of new species, death of existing species, and transition of species carrying one type of a trait to another. LÄS MER
18. Tree Rings as Sensitive Proxies of Past Climate Change
Sammanfattning : In the boreal forests of the Northern Hemisphere, time series of tree-ring width (TRW) and maximum density in the latewood (MXD) are highly correlated to local instrumental summer-temperature data and are thus widely used as proxies in high-resolution climate reconstructions. Hence, much of our present knowledge about climatic variability in the last millennium is based on tree-rings. LÄS MER
19. Probabilistic Modelling of Domain and Gene Evolution
Sammanfattning : Phylogenetic inference relies heavily on statistical models that have been extended and refined over the past years into complex hierarchical models to capture the intricacies of evolutionary processes. The wealth of information in the form of fully sequenced genomes has led to the development of methods that are used to reconstruct the gene and species evolutionary histories in greater and more accurate detail. LÄS MER
20. The Nitrogen Cycle in Soil - Climate Impact and Methodological Challenges in Natural Ecosystems
Sammanfattning : Nitrogen (N) is a fundamental element for life, and limiting in many terrestrial ecosystems. In non-N-fertilized ecosystems, the N inputs can be low, and the nutrient availability for plants is determined by the internal cycling of N. LÄS MER
