Sökning: "limnisk och marin ekologi Limnisk ekologi"

Visar resultat 26 - 30 av 94 avhandlingar innehållade orden limnisk och marin ekologi Limnisk ekologi.

1. 26. Benthic diatoms in the Gulf of Bothnia : Community analysis and diversity

   Författare :Svenja Busse; Michael Sullivan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Baltic Sea; Biodiversity; Biomass; Community ecology; Diatoms; Multivariate analysis; Navicula; Phytobenthos; Salinity gradient; Scale; Size; Water movement; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Ecological Botany; Ekologisk botanik;

   Sammanfattning : Benthic diatoms are valuable tools for biological monitoring and paleo-ecological reconstruction of past environmental conditions. This thesis aims at describing size-related properties of benthic diatoms and suggests that data assessment for community analysis can be improved by considering the importance of scale. LÄS MER

3. 27. Small-scale pattern and mobility of plant species in Alvar grassland

   Författare :Xiaobing Dai; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; association analysis; cattle dung; decomposition; limestone grassland; Gland; PASFRAN; soil seed bank type; Sweden; turn-around time; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Studies of the small-scale pattern, mobility of plant species and the effects of cattle dung deposition and decomposition on the soil seed banks and the above-ground vegetation were carried out in an alvar limestone grassland in Gettlinge, on the Baltic island of Öland, Sweden.A new method for pattern detection using transect data Patch Size Frequency Analysis (PASFRAN), was developed. LÄS MER

4. 28. Long-term changes in macroalgal vegetation on the Swedish coast : An evaluation of eutrophication effects with special emphasis on increased organic sedimentation

   Författare :Britas Klemens Eriksson; Francisco Xavier Niell Castanera; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Baltic Sea; Eutrophication; Fragmentation; Fucus vesiculosus; Functional group; Gullmar Fjord; Macroalgae; Long-term changes; Reproduction; Sedimentation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : In this thesis I examine and evaluate the effects of a documented large-scale eutrophication on macroalgal vegetation on the Swedish coast. During the past century the load of nutrients has increased manifold in the Baltic Sea area, increasing primary production and organic sedimentation significantly. LÄS MER

5. 29. Long-term studies of succession : Colonisation and seed banks

   Författare :Ulf Grandin; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ellenberg indicator values; genetic variation; long-term study; Lythrum salicaria; Moehringia trinervia; primary succession; seed bank; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. LÄS MER

7. 30. Attached Bacterial Communities in Lakes – Habitat-Specific Differences

   Författare :Ann-Louise Haglund; Lars Tranvik; Helmut Fischer; Bengt Boström; Erik Törnblom; Paul del Giorgio; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; bacteria; freshwater; sediment; epiphyton; bacterioplankton; metabolically active; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : For many years, the importance of microorganisms attached to surfaces in littoral zones and wetlands has been disregarded when describing aquatic ecosystem dynamics. Supporting evidence is scarce but convincing that these microbial communities are not only very productive but can often serve as major regulators of nutrient and carbon dynamics in many freshwaters. LÄS MER