Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1023/B:VEGE.0000029335.13948.87
Document Shareable Link
Title (Primary) Spatial pattern formation in semi-arid shrubland: a priori predicted versus observed pattern characteristics
Author Schurr, F.; Boßdorf, O.; Milton, S.J.; Schumacher, J.
Source Titel Plant Ecology
Year 2004
Department BZF; OESA
Volume 173
Issue 2
Page From 271
Page To 282
Language englisch
Abstract Ecologists increasingly use spatial statistics to study vegetation patterns. Mostly, however, these techniques are applied in a purely descriptive fashion without a priori statements on the pattern characteristics expected. We formulated such a priori predictions in a study of spatial pattern in a semi-arid Karoo shrubland, South Africa. Both seed dispersal and root competition have been discussed as processes shaping the spatial structure of this community. If either of the two processes dominates pattern formation, patterns within and between shrub functional groups are expected to show distinct deviations from null models. We predicted the type and scale of these deviations and compared predicted to observed pattern characteristics. As predicted by the seed dispersal hypothesis, small-scale co-occurrence within and between groups of colonisers and successors was increased as compared to complete spatially random arrangement of shrubs. The root competition predictions, however, were not met as shrubs of similar rooting depth co-occurred more frequently than expected under random shrub arrangement. Since the distribution of rooting groups to the given shrub locations also failed to match the root competition predictions, there was little evidence for dominance of root competition in pattern formation. Although other processes may contribute to small-scale plant co-occurrence, the sufficient and most parsimonious explanation for the observed pattern is that its formation was dominated by seed dispersal. To characterise point patterns we applied both cumulative _uni- and bivariate K-function_ and local _pair- and mark-correlation function_ techniques. Based on our results we recommend that future studies of vegetation patterns include local characteristics as they independently describe a pattern at different scales and can be easily related to processes changing with interplant distance in a predictable fashion.
Persistent UFZ Identifier
Schurr, F., Boßdorf, O., Milton, S.J., Schumacher, J. (2004):
Spatial pattern formation in semi-arid shrubland: a priori predicted versus observed pattern characteristics
Plant Ecol. 173 (2), 271 - 282 10.1023/B:VEGE.0000029335.13948.87