Impact of trees on the urban microclimate under climate change: Mechanisms and ecosys-tem services of urban tree species in temperate, Mediterranean and arid major cities

• Applicants: Professor Dr.-Ing. Stephan Pauleit; Professor Dr. Hans Pretzsch
• Subject Area: Forestry ; City Planning, Spatial Planning, Transportation and Infrastructure Planning, Landscape Planning
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 419147586

Urban green infrastructure, in particular urban trees, and their provided ecosystem services (e.g. transpirational cooling, carbon storage, shading) are important and modern tools to adapt cities to ongoing climate change. Despite the demand for climate-adapted urban green, it is largely unknown how different urban tree species react to climate change in different climate zones. Moreover, the urban climate with e.g. a higher temperature and changed radiation amounts as well as the urban site conditions for trees such as limited water availability, nutrient deficiency or limited rooting space may affect tree growth, tree vitality and the provided ecosystem services differently depending on climate zone and urban setting (street vs. public squares and parks). To quantify the benefits of trees for the urban microclimate in different climate zones, urban tree growth and ecosystem services will be studied in four countries with temperate climate (Germany), Mediterranean climate (Israel and Palestine) and arid climate (Israel and Jordan). Vice versa, the effects of the stand climate of various urban settings on tree growth and vitality will be analysed. Measurements will be conducted along a transect covering all countries and climate zones for studying growth patterns and morphological characteristics in six selected cities of Germany, Israel, Palestine and Jordan. Further on, permanent tree labs will be established, where climate variables, tree growth, transpiration and hence cooling in a high temporal and spatial resolution will be measured. On the basis of these measurements, growth and ecosystem services of urban trees can be modelled, and impacts of current and future climate scenarios can be analyzed by merging field data collection and modelling. Thus, new knowledge on the functioning of urban trees and the ecosystem services they provide in different climate zones for current and future climate conditions will be generated. In this novel joint project knowledge sharing between scientists and students of Germany, Israel, Palestine and Jordan will be increased (e.g. by training of young early stage researchers from Palestine and Jordan), people of different countries and climate zones will be brought together to find suitable solutions for future urban green planning benefitting for the wellbeing of the society. The project will result in new collaborations and knowledge for managing green infrastructure to adapt cities to climate change.

• DFG Programme: Research Grants
• International Connection: Israel, Jordan, Palestine
• International Co-Applicants: Dr. Elli Groner; Professor Jawad Hasan Shoqeir, Ph.D.; Dr. Maher Tadros
• Co-Investigator: Professor Dr. Thomas Rötzer
• Cooperation Partner: Dr. Gidon Winters