We congratulate Ariane Droin from our Earth Observation Research Cluster (EORC) and the Earth Observation Center (EOC) of the German Aerospace Center (DLR) on her successful defense of her PhD thesis.

The thesis is titled ” Permeabilität und Erreichbarkeit lokaler Nachbarschaften im urbanen Kontext. Eine geographische Analyse auf Basis räumlicher Netzwerke.” [engl. Permeability and accessibility of local neighbourhoods in an urban context. A geographical analysis based on spatial networks.]. Ariane explored how urban morphological aspects influence the spatial configuration, permeability and accessibility of local neighbourhoods. 

Here is the abstract of the PhD-Thesis: Active mobility, such as walking, has become a central strategy and an important starting point for urban planning measures. The aim is to make cities more liveable and sustainable. This has led to the development of various urban planning concepts such as the 15-Minute City, a concept that aims to ensure that all basic amenities are accessible within 15 minutes on foot or by bicycle. The importance of the design of the local neighbourhood for the subjective well-being of residents was recognised early on. Thus, it has always been an important goal of science to be able to establish the relationship between the objective urban environment and subjective perception in order to better understand which factors have the greatest influence on quality of life. The fact that no statistically reliable statements have been made to date could be due to unclear spatial delimitations and definitions of the local neighbourhood. In order to provide a better understanding of the local neighbourhood as a basis for further work, this dissertation presents a detailed analysis of the local neighbourhood from various points of view. This study explores how urban morphological aspects influence the spatial configuration, permeability and accessibility of local neighbourhoods. In a first step, local reference areas of different degrees of abstraction are compared with each other and related to different urban density levels. These provide the basis for the second step, in which permeability is calculated and compared across 78 large cities in Germany. In a third step, the local neighbourhood is expanded to include accessibility. Further, the influence of different urban development epochs on accessibility is examined based on urban structure types. The results clearly show that the local neighbourhood is a complex structure consisting of different urban structural building blocks. They prove that the local neighbourhood is highly functional and permeable for pedestrians in urban centres and old towns. In contrast, suburban areas dominated by single-family homes show low permeability and decentralised positioning of basic life functions. These aspects make walking more difficult. The urban centres studied have a permeability of around 60 % and single-family house areas of around 30 %. This difference is even more extreme in terms of accessibility: in old city centres, all basic functions of existence can be reached within an average of 10 minutes, while in single-family home areas it takes an average of 28 minutes. The findings of this study provide a sound basis for future analyses and urban planning measures. The aim is to improve certain aspects of the local neighbourhood in a more targeted manner in the interests of sustainability.

We would also like to refer to published papers related to her thesis.

• How does pedestrian permeability vary across cities due to local barriers and urban morphology? A fine-grained assessment for all large cities in Germany. https://www.sciencedirect.com/science/article/pii/S0198971524000449
• The Individual Walkable Neighborhood – A spatial concept for a realistic, individual perception of urban density. https://www.sciencedirect.com/science/article/pii/S0198971522001375
• Liveability in large housing estates in Germany – Identifying differences based on a novel concept for a walkable city. https://www.sciencedirect.com/science/article/pii/S016920462400149X
• Spatial Accessibility in Transition: Evaluating Urban Growth and Service Distribution in Westhoek, Belgium. https://ieeexplore.ieee.org/document/11076063
• Assessing the x-minuteness for urban structural types. https://ieeexplore.ieee.org/document/11076038