Driving forces of landscape change 1930-2000 in the Limmat Valley, Switzerland

This research identifies the driving forces that changed five towns from a traditional agricultural valley in 1930 to a periurban region in 2000. We linked 2746 landscape changes derived from a map-comparison with driving forces and aggregated the data to estimate the contribution of driving forces groups and administrative levels. By presenting an approach to quantify the contribution of major driving forces to landscape change this study contributes to method development in land change research.

Limmat Valley (photo Anna M. Hersperger, WSL)

Over the past decades, urban sprawl and agricultural intensification have enormously changed the traditional cultural landscape of the Swiss lowlands. This research aims to analyze the driving forces of urbanization, agricultural intensification, and greening in five municipalities of the periurban Limmat Valley, near Zurich, Switzerland. The main objectives of the research are (1) to quantify the change in urbanization, agricultural intensification, and greening, (2) to determine the driving forces of landscape change, (3) to determine the relative importance of socioeconomic, political, cultural, technological, and natural/ spatial driving forces, and (4) to establish from which administrative levels and spatial scales the most important driving forces originate.

METHOD

The study area includes the five towns Dietikon, Geroldswil, Oetwil a. d. L., Spreitenbach, and Würenlos (Figure 1). It is located approximately 13 km from the center of Zurich and covers 31.6 km² with roughly 42 300 inhabitants (census 2000). In 1930, four of the five towns have been rural villages with only Dietikon having some industry. Since then, the five towns experienced tremendous change in land cover and land use. Only the forest cover remained stable due to the strong legal protection of all forested land in Switzerland.

The study area, and the Swiss lowlands in general, has been subject to three main processes of landscape change: urbanization, agricultural intensification, and greening. Urbanization is characterized by an increase in the number of buildings and in transportation infrastructure. Agricultural intensification is characterized by a decline of many elements of the traditional agricultural landscape such as hedgerows and stone walls. An opposite trend, greening, describes the development in which new, ecological valuable landscape elements appear in the agricultural landscape. All three processes are included in this research.

Changes for the periods 1930–1956, 1957–1976, and 1977–2000 are documented based on a comparison of cartographic maps. A list of 73 potentially relevant driving forces is established based on document analysis. Based on further document analysis and expert interviews, 52 of them were found to be relevant primary driving forces for the documented landscape changes.

RESULTS

We found that in all three periods, urbanization was the most important process of change. Greening is steadily increasing in importance and surpassed agricultural intensification in the last period. Overall, as well as for urbanization, the economic driving forces, followed by political driving forces, are most important for landscape changes in all three periods. Cantonal driving forces are most important, followed by the national, local and international driving forces.

Specifically, we found that political driving forces contributed 26% to landscape change. Landscape changes like new roads and buildings, changes in the agricultural and forestry network, the loss of elements of the traditional agricultural landscape, new solitary trees, and new roadside slopes have been associated with political driving forces. Though many political driving forces shaped the landscape, depending on the question, a few crucial ones might be appropriate for understanding and managing many aspects of landscape change.

In order to understand the role of towns in shaping the changing landscape we further focused on municipal driving forces. Spatial configuration, taxes and subsidies, and local land use planning were the crucial local driving forces. Whereas all towns shared the same set of relevant local driving forces, they differed considerably in how strongly they were affected by these driving forces and how they reacted to them.

Publications

Hersperger, A. M. and M. Bürgi. In press. How do policies shape landscapes? Landscape change and its political driving forces in the Limmat Valley, Switzerland 1930-2000. Landscape Research.

Hersperger, A. M. and M. Bürgi. 2009. Going beyond landscape change description: quantifying the importance of driving forces of landscape change in a Central Europe case study. Land Use Policy 26: 640-648.

Hersperger, A., 2008: Wie verändert die Politik die Landschaft? Landschaftsveränderungen und ihre politischen Ursachen im Limmattal 1930-2000. [Abstract] Ballungsräume für Mensch und Natur. Forum für Wissen 2008: 76.

Hersperger, A. M. and Bürgi M. 2007. Driving forces of landscape change 1930-2000 in the urbanizing Limmat Valley, Switzerland. In Modelling land use change. Koomen E., Bakema A., Stillwell, J. Scholten H. (eds.) pp. 45-60. Springer.