Martina Koll-Schretzenmayr
p.03/ Editorial:
Alles neu – oder was?
Everything new – really?

Gabriel M. Ahlfeldt und Nicolai Wendland
p.05/ Die Zentralität war schon da!

This paper employs a multilevel market potential indicator to represent urban centrality generated by the urban railway network in Berlin from 1875–1935. Data on population are collected for the whole study period on the level of city districts (Ortsteile) and disaggregated to the level of 15 937 statistical blocks to enable detailed mapping and spatial aggregation on a micro-level. Disaggregation is conducted referring to built-up areas available in the form of historic maps which were digitized and georeferenced. The urban railway system, including network and stations, was digitally reproduced for the whole study period and merged with micro-level population data within a GIS environment to generate the centrality indicator. We find that preceding the emergence of West Berlin’s central business district during the 1920s, the area was excellently accessible by means of rail-based public transport. These findings confirm theoretical expectations that processes of urban decentralization lead to the emergence of sub-centers at those locations that are characterized by good accessibility and large market potential. For cities suffering from excessive congestion within their central business districts, our results suggest that city planners may successfully support the transformation of monocentric into polycentric cities by providing alternative sites with large market access based on an excellent transport infrastructure.

Bernd Mielke
p.15/ Hat eine hochwertige landschaftliche Gestaltung von Gewerbeflächen Einfluss auf deren Bodenwerte?

High landscape quality is a promising policy to enhance the chances of commercial sites on redeveloped brownfields. But does it really boost demand and increase the land values of these sites? This question was analysed within the framework of the Interreg IIIB-project: Creating a Setting for Investment. The study discusses methodological questions and gives empirical evidence for some of the benefits of landscape measures on commercial areas. The main results:

• The hypothesis that landscape measures within brownfield redevelopment projects result in higher land values could not be confirmed in the Ruhr area.

• However, further direct effects of high landscape quality which could not be quantified in the study should be taken into account as well: Landscape measures can contribute to cost reductions, for example, if contaminated soil is used to create hills instead of dumping it. Landscape measures reduce the NIMBY effect, thereby facilitating the development of the commercial area. To account for an unexpected rise in the demand for commercial plots, green spaces can partly be declared as “temporary nature” which can be changed into a commercial area if required. These effects can be decisive advantages for the investor and the municipality.

• Furthermore, the hypothesis that green spaces bring about higher land values is supported for surrounding residential property. The green spaces counteract a substantial deficit of the densely settled Ruhr region and upgrade the quality of life in the neighbourhood of the site. This can encourage the community to tap into local potential as well as face up to future demands. Furthermore, it can improve the setting for investment as a soft location factor. Therefore, high landscape quality can be profitable from a regional point of view.

Ursula von Petz
p.24/ Städtebau-Ausstellungen in Deutschland 1910 – 2010

This paper focuses on the history of a 100-year tradition of organizing town planning exhibitions in Germany: In Berlin in 1910, as part of a competition to design new housing estates, it was decided to exhibit the contributions and results to the public. The two events could be seen as crucial for the development of modern town planning for their content as well as procedure (or theory and practice). With sharp criticism against the 19th century city, Berlin and elsewhere, which consisted mostly of the “famous” rented blocks on a grid road system with hardly any open space inbetween, the alternative concepts presented in the exhibition for more modest, lower housing estates surrounded by green and open spaces has to be seen as a new approach to urban life. Besides, new forms of green and open space, not just as trees planted along a road or some modest playground or little park, but as an urban network, were claimed as a basic need for better urban living conditions that would reinforce youth, and offer citizens and young people the chance to live and grow up in “light, sun and air”. The article describes how the tradition of presenting town planning ideas to the public in special exhibitions, as well as discussing it in professional terms, which started nearly a century ago in 1910 in Berlin, has not only survived but continued to develop till today.

Michal Beim und Alexander Tölle
p.51/ Segregationsprozesse zwischen Altbauverfall und Suburbanisierung

The cities in Poland, as in other Central Eastern European countries, are currently subject to a massive suburbanisation process while the continuing decay of existing innercity housing stock is ever increasing. Using the example of the City of Posen, this article, based on the results of two empirical surveys (household interviews) in new suburban settlements as well as the inner-city tenement district of Jezyce, discusses the effects on the demographic and social structure of the city. There is a clear segregation process going on, with young, welloff households of prime working age with children leaving the inner city, while older, poorer households that rely on cheap, but uncomfortable housing remain. This leads to clear repercussions for any regeneration concept: the people left in the inner city have no financial basis for or interest in renewal activities. This is made worse by the uncoordinated privatisation policy of old municipal housing stock and leads to fragmented ownership structures. Untypical from a Western perspective, however, is the substantial building of new owner-owned flats in decaying inner-city areas. Well-off people are moving in, yet they are not typical “gentrifiers” as their interest does not extend to the old housing stock, and they do not appreciate innercity qualities, i. e., for implementing special lifestyles. Therefore, in future, a sharp segregation process may not only take place between certain city areas, but also between old and new housing stock within city districts.

Larissa Plüss
p.66/ Die Kantonsgrenze im Metropolitanraum Zürich

In the debate on metropolitan governance, the influence of the cantonal border has been given little attention so far. However, the need for action is particularly high in urban border regions where there are typically few contacts among the municipalities across the border. Thus, many border regions inevitably turn into peripheral regions. The aim of this article is to make a contribution to closing this research gap. It analyses the influence of a cantonal border on the municipal collaboration in the policy field of spatial planning. To this end, three urban agglomerations in the metropolitan area of Zurich are being compared: the urban region Limmattal and the urban agglomerations of Rapperswil-Jona-Rüti and Schaffhausen. These case studies point out the crucial components of the restraining effect of the cantonal border. With respect to the empirical findings, promising strategies for an improved municipal cooperation across the cantonal border are identified.

p.83/ Buchbesprechungen/ Book Reviews