Category Wild Urban Woodlands

Changes in vegetation

Vegetation management is a method of design combining human impacts and natural processes and offers an impression of the dynamics of nature.

Impacts/disturbance

In order to avoid the colonisation of woody plants like birches, the plant cover is partially removed at periodic intervals. Once again, mine spoil is heaped on the site and pioneer habitats are created.

These areas will either be sown with seeds of pioneer species or will be left to the natural succession of the existing vegetation which provides plenty of seed sources. The changing system of vegetation management

Подпись: Fig. 12. Vegetation management creating a pattern of different vegetation stages creates a pattern of different vegeta­tion stages...

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Deceleration of vegetation development

The vegetation development is slowed by heaping blast-furnace slag. This material offers an unfavourable growing medium with extremely alkaline conditions which have a toxic effect on plants, especially on deep-rooting species. These extreme habitat conditions lead to a low rate of succession. First mosses, e. g. Ceratodon purpureus and Bryum argenteum, colonise the slag substrate (Rebele and Dettmar 1996). Gradually the pH value is decreased through eluviation under the influence of rain. The substrate will then be populated by ruderal species like Chenopodium botrys and Arenaria serpyllifolia (Punz 1989).

Acceleration of vegetation development

For the acceleration of vegetation development, seeds of Senecio species (S. viscosus, S...

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Organisation: zonation

The water formations of the PLAIN provide the design framework. They structure and divide the area. Within this framework, the catwalk, steel – paths and lens viewpoints present fixed points.

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Fig. 8. Plan of the study site

The focus of the vegetation management is directed at primary stages of succession—from mosses to annuals to perennials—in order to preserve

the impression of the PLAIN’s vast expanse. The vegetation management creates a pattern of different vegetation types and divides the site accord­ing to the framework of the existing water areas.

The mine spoil areas which do not have any water formations are with­out vegetative cover. Next to the areas without vegetation, the natural vegetative development is artificially slowed.

The outlying area of the water forma...

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MtCRO-View

Analogously to the MACRO-view, the MICRO-view is established and alienated. In the lens boxes of the catwalk, Fresnel lenses also facilitate the ZOOM into the formations of the PLAIN and allow for discovery of the “form within the form”, in accordance with the phenomenon of self-simi­larity.

On the ground level of the PLAIN, viewpoints with lenses are installed. Magnifying glasses improve the MICRO-view of the different elements such as vegetation, bulk heaps and water formations, and also act as EYE- CATCHERS focussing the view of the observer to a micro-level that is usually not perceptible.

Through the MACRO – and MICRO-views, the ruderal vegetation typi­cal of industrial sites is visualised as an element of design, and an impres­sion of the dynamics of nature is presented.

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F...

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The phenomenon of change

A further aspect of the PLAIN of the sinking pond is the phenomenon of change. All the elements, the existing water areas supplied by rainwater, as well as the added elements like the bulk heaps and the vegetation, are characterised by change. The vegetation varies in expanse, coverage and shape. More changes become perceptible through vegetation management. In addition, the process of erosion changes the heaps of the coal material.

Levels of perception

The contemplation of the PLAIN is possible from different levels of per­ception: the MACRO-view offers an overview of the complete PLAIN whereas the MICRO-view allows the viewer to ZOOM into details.

MACRO-View

In the buildings of the coal-mine plant, the phenomenon of change may be documented, visualised and perceived by the visitor...

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The phenomenon of self-similarity

Подпись: Fig. 3. Panoramic view of the former sinking pond

The black PLAIN of the former sinking pond resembles a lunar landscape and forms a contrast to the surrounding landscape of the Saarkohlenwald woodlands. The completely open space of about 20 hectares appears as a huge plain lacking human scale, structured only by the water-areas.

image97"In the contours of the water areas of the PLAIN, the phenomenon of self-similarity or fractals, de­scribed by the mathematician B. Mandelbrot, can be found: basic structures recur regardless of the focus or the scale of the field of view (Mandelbrot 1987). The outlines of the water areas recur again and again in the shapes and contours.

The principle of self-similarity can be applied at larger scales, too...

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Post-industrial nature

Many mining areas in the Saarland have been recultivated with woody plants and are therefore hardly recognisable within the surrounding land­scape of the Saarkohlenwald woodlands. The goal of this project is to pre­serve the landscape formations, such as the mine slagheap and the filled-in sinking pond as a testimony to the industrial history and to document the huge human impacts on the landscape. The new landscape offers a unique appeal and a characteristic morphological language based on the industrial history. The aesthetic does not correspond with the usual images of “ideal nature” (Dettmar 1999). In Gottelborn, a designed intervention will em­phasise the potential of “post-industrial” nature, i. e...

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Post-Industrial Nature in the Coal Mine of Gottelborn, Germany: The Integration of Ruderal Vegetation in the Conversion of a Brownfield

Justina Drexler

Department of Landscape Architecture and Spatial Planning, TU Munchen

Context

This paper describes a design project that illustrates the integration of rud­eral vegetation in the conversion of a mining brownfield in the Saarland, Germany. The coal mine of Gottelborn is located on the periphery of the state capital of the Saarland, 15 km north of Saarbrucken. Gottelborn is situated on the northern outskirts of the peri-urban Saarkohlenwald wood­lands and represents one of the main industrial zones in the Saarland. Unlike other industrial regions, the Saarkohlenwald offers a sparse and ru­ral settlement structure (Fig. 1).

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Fig. 1. The landscape of Saarkohlenwald (photo: Wendl)

In the context of an industrial heritage network organised by the Com­mission “IndustrieK...

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Applicability

What can be applied in other cities or regions? Clearly such a fortunate case as the IBA Emscher Park with its start-up financing to serve as a cata­lyst occurs only rarely. Of course, the foresters entail labor costs— nevertheless, the development and maintenance of these sites is many times more cost-effective than conventional green spaces (see Dettmar 1997).

It is conceivable that a corresponding plan for care/custody could also be constructed from labor market projects, citizens’ or nature-conservation organizations, residents, or other kinds of volunteers. What is needed is a coordinating and supervisory site, but why shouldn’t this be located in the forestry or open-space department? Enthusiastic employees are, however, a prerequisite for this idea...

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The implementation

The idea of nurtured development, of maintenance and cultivation, quickly brought the historic image of the forester into the minds of the parties in­volved in the IBA Emscher Park. The employment of foresters in the abandoned areas is a logical step for the process of succession towards the forest, a process which happens relatively quickly on most sites. Federal and state forest regulations allow for even early stages of growth without a dominant woody layer to be defined as forest development areas. The for­mal transformation of a former industrial site into a forest at the level of land use planning will secure this status. The forest classification has sig­nificant advantages for the owners, at least when the change in the prop­erty valuation does not present economic problems...

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