Pattern and process in the plant community: Fifty years after A.S. Watt
Article first published online: 24 FEB 2009
1996 IAVS - the International Association of Vegetation Science
Journal of Vegetation Science
Volume 7, Issue 1, pages 19–28, February 1996
How to Cite
Van Der Maarel, E. (1996), Pattern and process in the plant community: Fifty years after A.S. Watt. Journal of Vegetation Science, 7: 19–28. doi: 10.2307/3236412
- Issue published online: 24 FEB 2009
- Article first published online: 24 FEB 2009
- Received 30 June 1995; Revision received 28 December 1995; Accepted 16 January 1996.
- Forest gap;
- Limestone grassland;
- Patch dynamics;
- Small-scale dynamics;
- Species mobility
Abstract. This paper is a tribute to A.S. Watt who published his ‘Pattern and process in the plant community’ almost 50 years ago. Watt's interpretation of the plant community “as a working mechanism, which maintains and regenerates itself” is still highly relevant, although the keywords have changed. ‘Process’ in Watt's view involves both upgrade and downgrade aspects, whereas ‘Pattern’ was not specified, neither quantified. Nowadays, process is mainly approached as ‘disturbance’, that is natural disturbance and ‘pattern’ as patch structure. Together they make up the ‘patch dynamics’ of the community. Some implications of patch dynamics for phytosociology are discussed. A ‘Wattian’ concept of the plant community combines the Gleasonian idea of individualistic behaviour of species with the Clementsian (or rather Braun-Blanquetian) notion of community dynamics. Later work by Harper (demography), Grubb (regeneration niche) and earlier work of Sernander (forest gap dynamics) is significant for the understanding of the patch-dynamic nature of the community.
Recent interest in plant species mobility can easily be linked to the concept of patch dynamics. Examples of mobility in a limestone grassland are given and a system of mobility types is proposed.
Some perspectives for the study of patch dynamics are mentioned. Numerical pattern analysis should have a more prominent place in this type of study; the significance of the study of small permanent plots in a stand is emphasized, and unprejudiced demographic studies, as well as experimental studies of small-scale species replacement are recommended.