Sökning: "Population Ecology"

Visar resultat 1 - 5 av 482 avhandlingar innehållade orden Population Ecology.

1. 1. Evolutionary ecology of arctic char (Salvelinus alpinus (L.)) : Intra- and interspecific interactions in circumpolar populations

   Författare :Johan Hammar; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Arctic char; Salvelinus alpinus; biogeography; niche; life history; population ecology; intra- and interspecific interactions; cannibalism; competition; landlocked; marginal populations; species border; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis examines a suite of ecological and genetic mechanisms influencing the fundamental and realized niche borders of European and North American populations of the Arctic char (Salvelinus alpinus (L.)) species complex in allopatry as well as in sympatry with brown trout (Salmo trutta) or brook trout (Salvelinus fontinalis). LÄS MER

3. 2. Ecology across Boundaries : Food web coupling among and within ecosystems

   Författare :Pia Bartels; Peter Eklöv; Lars J. Tranvik; Daniel E. Schindler; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; cross-ecosystem; food web; habitat coupling; terrestrial-aquatic linkages; subsidy; allochthonous; lake ecosystem; population divergence; trait variation; Terrestrial; freshwater and marine ecology; Terrestrisk; limnisk och marin ekologi; Freshwater ecology; Limnisk ekologi; Biology; Biologi; Biologi med inriktning mot limnologi; Biology with specialization in Limnology;

   Sammanfattning : Cross-boundary movements of energy and material are ubiquitous. Freshwater ecosystems receive nutrients, dissolved, and particulate organic matter from adjacent terrestrial ecosystems, whereas terrestrial ecosystems mainly receive prey organisms and detritus deposited by physical processes such as floods from freshwater ecosystems. LÄS MER

4. 3. Population dynamics of tundra-living grey-sided voles

   Författare :Per Ekerholm; Lauri Oksanen; Rolf Anker Ims; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Population dynamics; Tundra; Grey-sided vole; Cycles; Vole specialist predators; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; zooekologi; Animal Ecology;

   Sammanfattning : This thesis deals with the dynamics of tundra living voles with emphasis on the most common one, the grey-sided vole (Clethrionomys rufocanus). The tundra area chosen for the study was Finnmarksvidda, a vast flatland in northernmost Norway. LÄS MER

5. 4. Stopover Ecology of Mallards : Where, when and how to do what?

   Författare :Daniel Bengtsson; Jonas Waldenström; W. Michael Eichholtz; Linnéuniversitetet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Age characters; body condition; departure decision; effects of influenza A virus; habitat selection; mallard; movement; Ottenby Bird Observatory; stopover ecology; weather; wild birds; Ecology; Ekologi;

   Sammanfattning : The mallard (Anas platyrhynchos) is the most numerous and widespread duck in the northern hemisphere and a model species in ecology and harvest management. Migration is a crucial life stage for many birds and understanding the drivers of migration has important implications for conservation biology and assessment of animal population responses to global changes. LÄS MER

7. 5. Species interactions govern evolutionary and ecological effects of population harvesting

   Författare :Anna Gårdmark; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; population harvesting; species interactions; ecological community; Ekologi; Ecology; competition; predation; fisheries; spatial dynamics; maturation; population dynamics; life-history evolution; adaptation;

   Sammanfattning : Harvesting changes population abundance and can affect adaptation of several life-history traits. Harvesting can also have indirect effects ? effects on non-target species and secondary effects on target species ? because interactions between species in a community determine the relevant ecological and evolutionary feedback environment. LÄS MER