Ecological Growth Processes of Urban Trees, Provision of Ecosystem Services and Improvement of Monitoring and Management of Urban Forests (TreeEcos)

As trees in the city are exposed to significantly different environmental conditions than in the forest, many findings on growth dynamics from forestry science cannot be directly transferred to urban trees. In the city, trees are exposed to more stress factors and there are fewer resources available than in the forest.
The aim of the Institute for Technology Assessment and Systems Analysis (ITAS) in the URBORETUM project is therefore to gain a better understanding of how trees grow in the city. How is growth related to the availability of resources (water, nutrients, root space)? What is the resource uptake and resource utilization efficiency of different tree species? To answer these questions, sensor-based growth measurements will be carried out until 2026. Based on these measurement results, tree species-specific allometric equations for the crown volume and leaf area of urban trees will be developed. In many cases, detailed data is required to monitor the development of trees. Collecting this data involves a great deal of effort through direct measurements. In practice, this effort is often not feasible for the responsible authorities. For this reason, so-called allometric equations are to be developed. With the allometric equations we have developed, more can be calculated from less data. We take advantage of the fact that organisms grow proportionally. We want to find out which equations apply to urban trees, for example to be able to deduce the biomass of a tree from the trunk diameter, height and tree species. We also want to understand the ecological processes behind the biotic and abiotic factors that influence trunk growth and fine root formation (production ecology).
Another aim is to find out how different ecosystem services (such as the cooling effect of trees or the provision of microhabitats) are related to the tree species. For this purpose, various measurements are carried out and residues of eDNA(environmental DNA) of the species occurring in the microhabitats are analyzed.
The results obtained in TreeEcos are intended both to expand scientific knowledge and to support city administrations with practical knowledge for the monitoring and management of urban tree populations.