Landscape-ecological mapping as basis for management of the Amsterdam waterwork dunes
Ehrenburg, A.; Baeyens, G. (1992). Landscape-ecological mapping as basis for management of the Amsterdam waterwork dunes, in: Carter, R.W.G. et al. Coastal dunes: geomorphology, ecology and management for conservation: Proceedings of the 3rd European Dune Congress Galway, Ireland, 17-21 June 1992. pp. 407-418
In: Carter, R.W.G.; Curtis, T.G.F.; Sheehy-Skeffington, M.J. (Ed.) (1992). Coastal dunes: Geomorphology, ecology and management for conservation: Proceedings of the 3rd European Dune Congress Galway, Ireland, 17-21 June 1992. A.A. Balkema [etc.]: Rotterdam. ISBN 90-5410-058-3. 533 pp., meer
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| Auteurs | | Top |
- Ehrenburg, A.
- Baeyens, G.
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| Abstract |
In the Amsterdam Waterwork Dunes (3300 ha) near Haarlem, The Netherlands, a landscape-ecological mapping (scale 1:5000) exercise has been carried out, using a method based on the concept of landscape unitS. Landscape unitS are defined as ccomplexes of ecosystems, recognisable in the field and on aerial photographs as 'holistic' units. This method was originally developed for landscape-ecological mapping with scales varying between 1:25000 and 1:50000 (During,1988). Since 1980 this method has also been used to make maps with larger scales (1:10000 and 1:5000). This method of landscape mapping is especially useful in landscapes with extremely small-scale vegetation patterns (mosaics), like the dune landscape. A classical vegetation map would be very laborious and desultory in this case. The classification of landscape units is based predominantly on vegetation; geomorphology, soil and hydrology play a secondary role. All abiotic factors are reflected in the composition and strUctUre of the vegetation, which is used therefore as the main guiding principle. By comparing the results of this landscape-ecological study (1988-1989) with a similar map of 1981-1982, the major changes have been a study area a west-east zonation of main landscape types can be distinguished. Developments in the landscape in the period 1981/1982 to 1988/1989 only cause changes in sub-landscape types (vegetation succession). Only incidentally does vegetation succession lead to landscape succession at the main landscape type level. The following developments occurred most frequently: 1. the expansion of Calamagrostis epigejos in different landscape types (grass encroachment). 2. an increase in coverage of scrub, mostly Sea Buckthorn (shrub encroachment). 3. an increase of dune slack landscape within different landscape types. The analysis of developments in vegetation enables us to predict the local succession for the coming decades in general termS. These predictions and the landscape-ecological knowledge of the area, provide the fundamental tools for management choices. Choices made in this area for a more natUral way of management are: 1. not to retard, and maybe even stimulate, the natural development of blowouts in the sea-bound R-landscape;2. to counteract the man-induced (air pollutants), accelerated developments such as decalcification in originally natural erosion and rejuvenation. 3. to counteract grass and shrub encroachment due to similar processes in the originally more open landscape types. Grazing is an increasingly used method to cope with such encroachment problems. 4. certain landscape types with an exceptionally floristic and historical importance to be maintained, because they would otherwise develop into other landscape types and disappear. In the Amsterdam Waterworks Dunes, cattle are introduced to maintain the 'coastal village' landscape type. |
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