Sökning: "Rare species"
Visar resultat 11 - 15 av 142 avhandlingar innehållade orden Rare species.
11. Microbially mediated manganese oxides enriched in yttrium and rare earth elements in the Ytterby mine, Sweden
Sammanfattning : Microorganisms are able to manipulate redox reactions and thus exert extensive control on chemical speciation and element partitioning in nature, affecting the formation and dissolution of certain minerals. One of these redox active elements is manganese (Mn), which in its oxidized states (III/IV), commonly forms Mn oxide-hydroxide minerals. LÄS MER
12. Structure and Stability of Ecological Networks : The role of dynamic dimensionality and species variability in resource use
Sammanfattning : The main focus of this thesis is on the response of ecological communities to environmental variability and species loss. My approach is theoretical; I use mathematical models of networks where species population dynamics are described by ordinary differential equations. LÄS MER
13. Resonant Inelastic X-ray Scattering of Rare-Earth and Copper Systems
Sammanfattning : Rare earths and copper systems were studied using X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). The use of monochromased synchrotron radiation and improved energy resolution for RIXS made possible to obtain valuable information on the electronic structure in 4f, 5f and 3d systems. LÄS MER
14. Spatiotemporal monitoring of rare and elusive saproxylic beetles - A pheromone based approach
Sammanfattning : Forest ecosystems are under severe pressure from global environmental changes and increasing demands of wood-related products. During the last century, intensified management regimes have led to the decline of many previously common forest habitats, with catastrophic effects for biodiversity. LÄS MER
15. Patterns of evolution in a young species, the Baltic seaweed Fucus radicans
Sammanfattning : To be able to interpret patterns of biodiversity it is important to understand the processes by which new species evolve and how closely related species remain reproductively isolated and ecologically differentiated. This thesis centers on the evolution of the two brown algae Fucus radicans and Fucus vesiculosus in the Baltic Sea, where Fucus radicans very recently diverged from F. LÄS MER
