Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

• Main Author: Pettersson, Julia
• Format: Bachelor Thesis
• Language: Swedish
• Published: UmeÃ¥ universitet, Institutionen för ekologi, miljö och geovetenskap 2015
• Subjects: boreal forest; forest fire; connectivity; fire-related insects; northern Sweden; Biological Sciences; Biologiska vetenskaper; Northern Sweden
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-99488

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests. The aim of this study was to investigate if a higher connectivity between burnt forests leads to an increased occurrence of fire-related insects. The study also attempts to determine in what way connectivity and other variables in a burnt forest, such as amount of living and dead wood, distance to the coast and altitude, affects fire-related species. To investigate this, six burnt forests in Västerbotten County were sampled for fire-related insects. The sites were chosen along a gradient from high to low connectivity and close to far from the coast. The results showed that there are too few burnt forests in Västerbotten County to conduct a study of this magnitude. Still, the results provide an insight in how different environmental variables affect the number of fire-related species. The results showed a trend that increasing amount of living and dead wood and longer distance from the coast increase the local richness of fire-related species. Concerning the main aim in the study about connectivity, the analysis gives no support to either accept or reject the hypothesis.