Sökning: "habitat fragmentation"

Visar resultat 16 - 20 av 122 uppsatser innehållade orden habitat fragmentation.

1. 16. Population genetic analyses inform conservation of the endangered Clouded Apollo (Parnassius mnemosyne) butterfly in Sweden

   Master-uppsats, Uppsala universitet/Institutionen för biologisk grundutbildning

   Författare :Veronika Mrazek; [2022]
   Nyckelord :Clouded apollo; Parnassius mnemosyne; Lepidoptera; Genetic diversity; Differentiation; Inbreeding; Demographic history; Gene-flow;

   Sammanfattning : The clouded apollo (Parnassius mnemosyne) is a palearctic butterfly with a wide distribution across Eurasia. In recent decades, however, the species has declined in many parts of its distribution range. LÄS MER

3. 17. Effects of past fragmentation and habitat loss and current management methods on the changes in vascular plant communities. : An evaluation of extinction debt in semi-natural grasslands in Sweden

   Kandidat-uppsats, Uppsala universitet/Institutionen för biologisk grundutbildning

   Författare :Adina Sennblad; [2021]
   Nyckelord :;

   Sammanfattning : Habitat loss and fragmentation are believed to be two of the main reasons for high extinction rates of species, resulting in decreased biodiversity. According to the island biogeography theory, the species richness in a patch, here a semi-natural grassland, is dependent on the landscape composition, and therefore changes in the landscape composition will result in changes in the species richness of the grassland. LÄS MER

4. 18. Flower-visiting insects benefit from forest in the surrounding landscape

   Kandidat-uppsats, Linköpings universitet/Institutionen för fysik, kemi och biologi

   Författare :Emilia Sundell; [2021]
   Nyckelord :Apoidea; clear-cut; Coleoptera; forest; Hymenoptera; landscape composition; Lepidoptera; Syrphoidea;

   Sammanfattning : Habitat loss and fragmentation due to agricultural practices are causing worrying declines in insect diversity and biomass. Agricultural intensification, among other things, have led to a decline in semi-natural grasslands. Forest in the surrounding landscape can have a positive effect on species abundance in grasslands. LÄS MER

5. 19. Direct and indirect effects of roe deer (Capreolus capreolus) herbivory on an island population of Chequered blue butterfly (Scolitantides orion).

   Master-uppsats, Uppsala universitet/Institutionen för biologisk grundutbildning

   Författare :Alexandra Johansson; [2021]
   Nyckelord :Scolitantides orion; Chequered blue butterfly; oviposition; oviposition behaviour; Indirect and direct effects; herbivory;

   Sammanfattning : Herbivory by ungulates is a known agent of disturbance in many ecological systems around the globe. At high abundances and through a selective foraging behaviour herbivory may inflict significant direct and indirect effects on local plant and animal communities. LÄS MER

7. 20. Effects of population size, density and local environment on the population dynamics of the fragrant orchid (Gymnadenia conopsea)

   Master-uppsats, Uppsala universitet/Institutionen för biologisk grundutbildning

   Författare :Kasper Kupka; [2021]
   Nyckelord :Demography; Gymnadenia conopsea; local habitat; matrix models; orchids; population density; population size; stochastic growth rate; soil organic matter; quasi-extinction probability;

   Sammanfattning : A wide majority of orchid populations are decreasing due to habitat fragmentation and to changes in land management. Population size, density and habitat quality are factors that are expected to be positively related to the viability and future growth of a population. LÄS MER