City trees in danger: climate change threatens our green oases!

City trees in danger: climate change threatens our green oases!

Urban trees are an indispensable part of urban spaces, but face increasingly complex challenges. Drought, disease and tree felling threaten their growth and thus their ability to cushion the negative effects of climate change in cities. Stephan Pauleit, Professor of Strategy and Management of Landscape Development at the Technical University of Munich, emphasizes the urgent need to promote sustainable urban planning to improve the integration of nature in urban environments.

Pauleit heads the Center for Urban Nature and Climate Adaptation and is working on an important project together with Thomas Rötzer, Professor of Ecological Modeling, and Barbara Darr, Professor of Urban Forest Management. This aims to gain a comprehensive picture of urban trees and to better understand their condition and distribution. In this context, Martin Geilhufe, state representative at the BUND Nature Conservation, highlights the importance of improved data collection.

The citizen science project “My Tree”

A central element of the project is the “My Tree” app, which enables citizens to record their city trees. The app allows users to document trees by providing information on location, tree species, condition, root area, trunk and tree crown. You can also upload photos of the trees, which will be checked and verified by experts. Another feature of the app allows users to document the animals and plants that live on the trees, helping to create a comprehensive inventory of urban trees in communities such as tum.de reported.

The app is not only a data collection tool, but also helps raise awareness of the ecological roles of urban trees. These trees provide numerous ecosystem services, including improving microclimate, storing carbon, and reducing runoff. In view of climate change, the role of these trees in cities is becoming increasingly important, as is also evident in the completed CityTree I and II projects.

Research concerns and future perspectives

The CityTree II project, financed by the Bavarian State Ministry for the Environment and Consumer Protection, investigates the growth behavior, environmental performance and prospects of city trees under climate change conditions. Researchers use an environmentally and climate-sensitive individual tree growth model to analyze the development of trees from youth to adulthood. The focus is, among other things, on tree species such as the winter linden tree and the black locust as well as newly introduced species such as the plane tree and the chestnut zsk.tum.de reported.

The findings from these studies are to be published in the expanded edition of the guide “Guide to Urban Trees in Climate Change”, which will be published in 2024. The guide offers practical advice for the management of urban trees in Bavaria and is also made available in digital form. Users should be able to carry out simulations for individual trees and their specific site conditions in order to make it easier to choose the optimal tree species.

The comprehensive research project and the involvement of the public through citizen science are intended to help strengthen the sustainability of urban planning and specifically support the function of urban trees in climate change. With the increasing importance of urban nature, it is important to act actively and ensure the positive influence of trees on the urban ecosystem, as are the projects of zsk.tum.de demonstrate.