Project description A3 - Project completed
Scientific advisors
Prof. Dr. T. Tscharntke, Prof. Dr. Steffan-Dewenter
Project
Arthropod communities and multitrophic interactions across a tree diversity gradient in a Central European deciduous forest PDF
The relationship between biodiversity and ecological functions such as herbivory is a topical question in ecology. Species-rich semi-natural forests have become rare in temperate regions with possible impacts on arthropod diversity, herbivory rates and pest outbreaks. In experimental grassland, plant species richness has been shown to correlate with insect diversity and herbivory, but little is known for mature forests with different tree species diversity. We examined herbivory of beech (Fagus sylvatica), Norway maple (Acer platanoides) and sycamore maple (Acer pseudoplatanus) saplings in forest stands of different tree diversity, and expected insect herbivory to decrease with increased tree species richness. We further hypothesized that arthropod species richness and would be higher in more diverse forest stands.
We found that taxa responded in different ways, but generally arthropod species richness and predator/prey ratios increased while herbivory decreased across the tree diversity gradient. These results support our hypothesis that maintaining high tree diversity in semi-natural forests is important for biodiversity and ecosystem functioning.
Methods
- flight interception traps (canopy)
- trap nests for bees and wasps in (canopy and understorey)
- estimation of leaf area loss in tree saplings
- recording of galls and mines
- observation of herbivores and predators
- beating samples