Sökning: "freshwater and marine ecology"

Visar resultat 31 - 35 av 129 avhandlingar innehållade orden freshwater and marine ecology.

1. 31. Factors Affecting the Distribution of Rocky-Shore Macroalgae on the Swedish Coast : Morphological, Physiological, Reproductive and Genetic Aspects

   Författare :Gustav Johansson; John Raven; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : The aim of this thesis was to examine factors affecting the distribution of macroalgal species both vertically (depth zonation) and geographically along the Baltic Sea salinity gradient. Interactions between the physical environment and basic biological traits of the algae are emphasised. LÄS MER

3. 32. Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change

   Författare :Line Gordon; Carl Folke; David Molden; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; freshwater; green water; ecosystem services; integrated water resources management; food production; land use and land cover change; vulnerability; resilience; hydrological cycle; global change; Australia; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : The purpose of this thesis is to analyse interactions between freshwater flows, terrestrial ecosystems and human well-being. Freshwater management and policy has mainly focused on the liquid water part (surface and ground water run off) of the hydrological cycle including aquatic ecosystems. LÄS MER

4. 33. Macroalgae in the Baltic Sea : responses to low salinity and nutrient enrichment in Ceramium and Fucus

   Författare :Lena Bergström; Lars Ericson; Lena Kautsky; Erik Bonsdorff; Christine A Maggs; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; adaptation; asexual reproduction; Baltic Sea; Gulf of Bothnia; salinity; macroalgae; nutrients; sexual reproduction; stress; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : The brackish Baltic Sea is a marginal environment for both marine and freshwater species. The rate of ecological differentiation is presumably high due to strong selection pressure from a gradient of decreasing salinity that has been present in its current state for only about 3 000 years. LÄS MER

5. 34. The nitrogen economy of mountain birch : As related to environmental conditions and genotype

   Författare :Martin Weih; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Betula pubescens ssp. czerepanovii; growth; nitrogen; subarctic; temperature; ultraviolet radiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Responses of mountain birch growth to changed environmental conditions arestrongly affected by birch genotype, and nitrogen economy is a key factor influencingthe winter survival of first-year seedlings. These are some of the findings of a series ofstudies, in which growth, nitrogen economy and winter survival were analysed usingpot-grown seedlings of mountain birch (Betula pubescens ssp. LÄS MER

7. 35. Resource aquisition and allocation in lichens

   Författare :Lena Dahlman; David Richardson; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Amino acid; Arginine; carbohydrates; chlorophyll; ergosterol; microclimate; Lichen growth; nitrogen stress; photosynthesis; proteins; respiration; Symbiosis lichen ; nitrogene uptake; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Lichens are fascinating symbiotic systems, where a fungus and a unicellular alga, most often green (bipartite green algal lichens; 90% of all lichens), or a fi lamentous cyanobacterium (bipartite cyanobacterial lichens; 10% of all lichens) form a new entity (a thallus) appearing as a new and integrated organism: in about 500 lichens the fungus is associated with both a cyanobacterium and an alga (tripartite lichens). In the thallus, the lichen bionts function both as individual organisms, and as a symbiont partner. LÄS MER