Central Research Questions
This thesis is led by Nicklas Jansson and explores the ecology and taxonomy of saproxylic beetles through the following questions: How does species diversity of saproxylic beetles vary across ancient oak forests in Europe? What is the taxonomic status of existing species, and are there new species yet to be described? What ecological functions and interactions do saproxylic beetles have within their habitats? And how do beetle diversity and ecological traits vary with latitude and other environmental gradients?
Background and Aims
Saproxylic beetles, which depend on dead or decaying wood for at least part of their lifecycle, are critical to forest ecosystems. This project is an extensive ecological and taxonomic investigation of saproxylic beetles associated with ancient oak forests across Europe. The study aims to deepen the understanding of their diversity, distribution, and ecological roles, providing insights essential for their conservation. Specific objectives include documenting the species richness of saproxylic beetles across diverse European habitats, identifying and describing new species while clarifying the taxonomy of existing ones, investigating the ecological functions and interactions of saproxylic beetles within their habitats, and analyzing how beetle diversity and ecological traits vary with latitude and other environmental gradients. Together, these objectives aim to provide data that can inform conservation strategies for preserving beetle diversity and forest health.
Methods
The study encompasses 28 sites across Europe, selected for their significant populations of old hollow oak trees, which are key habitats for saproxylic beetles. Beetles are collected using flight interception traps installed on oak trees, capturing specimens during their active flight periods over several months. Specimens are identified to the species level by experts, focusing on 11 taxonomic families and their respective feeding guilds. Statistical models are employed to examine patterns of species richness and body size in relation to latitude and other variables.