Sökning: "size structured populations"

Visar resultat 11 - 15 av 20 avhandlingar innehållade orden size structured populations.

1. 11. Habitat use in fish communities : size- and environment-dependent mechanisms affecting biotic interactions and population regulation

   Författare :Ulrika Beier; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Through the influence of abiotic factors, the habitat use of organisms affects their metabolism as well as other species- and size-dependent individual-based rates. The habitat-specific performances of individuals interacting in different habitats thereby affect biotic interactions. LÄS MER

3. 12. Ontogenetic bottlenecks : effects on intraguild predation systems and ecosystem efficiency

   Författare :Birte Reichstein; Lennart Persson; André M. De Roos; Priyanga Amarasekare; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mixed interactions; cannibalism; life-history omnivory; ontogenetic niche shift; biomass overcompensation; biomass production; ontogenetic asymmetry; indirect effects; biology; biologi; zooekologi; Animal Ecology;

   Sammanfattning : Size-dependent differences between individuals in size-structured organisms have fundamental effect on population and community dynamics. Intraguild predation (IGP) is one specifically interesting constellation that often arises when two size-structured populations interact. LÄS MER

4. 13. Opportunities in small population breeding in black cottonwood : or The little population that could

   Författare :Rami-Petteri Apuli; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

   Sammanfattning : Small and structured populations are problematic for breeding due to low levels of genetic variability and increased levels of linkage disequilibrium (LD). The increased LD causes problems with utilization of common genomic tools and may lead into increased accruement of deleterious alleles through the intense selection and bottlenecks characteristic of breeding. LÄS MER

5. 14. Carex humilis - a caespitose clonal plant: ramet demography, ring formation, and community interactions

   Författare :Sofie Wikberg; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ramet density; Plant ecology; Växtekologi; ramet population dynamics; aggregated ramets; intravaginal; phalanx type; LTRE; matrix model; fitness; dry grassland; hollow crown; fairy ring; central die back;

   Sammanfattning : Carex humilis forms rings of densely aggregated ramets in dry grassland vegetation in Central Europe. In the thesis I conclude that ramet demography is important both for analyzing fitness in clonal plants and for understanding how C. humilis rings are formed. I studied the ramet demography of C. LÄS MER

7. 15. Metapopulations dynamics and sex-specific resource allocation in Silene dioica

   Författare :Elisabet Peedu; Pär Ingvarsson; Barbara Giles; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Silene dioica; Skeppvik Archipelago; Metapopulation Dynamics; Population Genetic Structuring; Genetic Diversity; Gene Flow; Sex-Specific Resource Allocation; Cost of Reproduction; Life-History Theory; Sexual Dimorphism; Reproductive Effort; biology; biologi; evolutionär genetik; evolutionary genetics; ekologisk botanik; Ecological Botany;

   Sammanfattning : Rising archipelagos provide unique settings for the study of the temporal and spatial dynamics of their biota. This offers the possibility to study the ecology and genetics of early successional processes; both between islands that differ in age and within islands when already established organisms have to keep pace with the changing environment. LÄS MER