The aim of this preliminary study was a comparison of the arthropod diversity of three native and closely-related non-resident tree species at an urban site.
In times of climate change, non-resident tree species show a higher stress tolerance, which in turn often leads to a higher vitality. This is the reason why they are also called ‘urban climate trees’.
At present, it is unknown how the stress tolerance of these species affects the communities of invertebrates that use the treetops, including herbivorous and plant-sucking insects. The individuals in this community could be distributed relatively evenly among the existing species; however, certain species could also become dominant, reproduce massively and damage the tree or impair its function as a city tree.
The study at hand thus aimed at comparing urban climate trees and native trees regarding their vulnerability to pest infestation. This includes the characterization of the canopy communities. These data also allowed analysis of the extent to which non-resident city trees contribute to sustaining biodiverse tree canopies.
Fieldwork of this study was carried out within the framework of a master thesis in biology over one growing season based on a screening of the biodiversity of insect and arachnid species on native and non-resident trees species of the climate change project „Urban Green 2021“ (funded by StMELF) in Wuerzburg. Due to urban heat island (UHI) effects being intensified by climate change, predominately non-resident trees will be planted in the future at urban street sites.
This preliminary study is a start to establish a reliable database for a comparative evaluation of the biodiversity of canopy inhabiting arthropods of native and non-resident trees species. The results are meant to be used, for example, as information for environmental protection agencies and nature conservation associations as well as for recommendations to Bavarian municipalities concerning the design and planning of climate tolerant green infrastructure.
The project was carried out jointly by the „Bavarian Institute for Viticulture and Horticulture” Veitshöchheim (Dr. Susanne Böll) and the Biocenter of the University of Wuerzburg, Chair of Animal Ecology and Tropical Biology (Dr. Dieter Mahsberg).