Spatial Pattern Formation in Plant Communities

Horizontal spatial pattern is one of the most conspicuous features of plant communities. Most air photographs of any habitat show unequal arrangement of individuals in horizontal space, aggregation of individuals belonging to one plant species, and many different types of spatial correlation if many species are involved. This horizontal spatial heterogeneity was noticed by early botanists and has spawned a large body of literature on its identification and interpretation (for a review, see [11]). Spatial patterning is one of the major research subjects in plant ecology: understanding how this ubiquitous phenomenon comes into being is likely to be one of the essential elements in understanding how plant communities are assembled and how they work. However, spatial patterns are often much noisier than many other biologically interesting patterns, highlighting the role of stochastic events that can overwhelm the underlying regularities — or questioning the existence of such regularity at all. Spatial pattern has also been invoked as having important dynamical consequences for plant communities [32, 35]. Widespread as the patterns in plant communities may be there is still no complete consensus on the processes that generate and maintain them, and on the dynamical consequences they may have. In this paper, we will briefly review current research on this subject, and try to highlight current developments in the area.