Sökning: "population growth rate"
Visar resultat 6 - 10 av 225 avhandlingar innehållade orden population growth rate.
6. Variation in age and size at maturation in two benthic crustaceans in the Gulf of Bothnia
Sammanfattning : The thesis deals with variation in age and size at maturation in Saduria entomon and Pontoporeia affinis along a depth gradient in the Gulf of Bothnia, Sweden. I have analysed at what sizes and ages animals should mature in relation to growth and mortality conditions. LÄS MER
7. Dynamics of omnivorous crayfish in freshwater ecosystems
Sammanfattning : In this thesis I examine the dynamics of crayfish in streams and lakes. I have studied the influence of abiotic and biotic factors on abundance, growth, trophic position, niche breadth, and recruitment of crayfish, by conducting field studies, an outdoor channel experiment and timeseries analysis. LÄS MER
8. Population size, viability and genetic diversity in the orchid Gymnadenia conopsea
Sammanfattning : In this thesis, I combined controlled crosses with genetic and demographic data to examine how a main conservation value indicator, population size, was associated with estimates of population viability. I focused on the still common, but decreasing, perennial orchid Gymnadenia conopsea at two spatial scales—locally on the island Öland, in SE Sweden, and regionally across Scandinavia. LÄS MER
9. Plant ecological studies related to restoration of a degraded ecosystem in central Tanzania
Sammanfattning : Kondoa Irangi area is among the most degraded ecosystems in Central Tanzania as a result of heavygrazing, fire, collection of fuelwood and improper cultivation practices. The restoration process of thisdegraded ecosystem through natural regeneration is slowed by the semi-arid climate of the area combinedwith poor soil nutrient status. LÄS MER
10. Public Health Aspects of Preterm Birth. Studies using Scandinavian population-based data
Sammanfattning : Background: Preterm birth is an unresolved serious global health problem. Research must be multi-disciplinary, with assessment of risk factors and causative agents at many levels of observation. Such an important level is the public health aspect of preterm birth. LÄS MER