Contrasting spatial pattern and pattern forming processes in south west Western Australia natural and restored shrubland communities
Miller, B., Perry, G., Enright, N. and Lamont, B. (2009) Contrasting spatial pattern and pattern forming processes in south west Western Australia natural and restored shrubland communities. In: 19th Conference of the Society of Ecological Restoration International, 24 - 26 August, Perth, Western Australia.
Restored plant communities provide a uniquely simplified context for studying difficult questions such as how ecological processes structure plant communities. Spatial pattern among individuals is an important component of community structure, and plays a role in determining ecosystem properties and restoration trajectories in plant communities. Nevertheless, the role of spatial pattern has previously received scant attention in a restoration context. We compared 87 plant species patterns from two samples of vegetation restored after sand-mining, with 233 patterns of species in four nearby natural reference sites in fire-prone, species-rich shrublands in south-west Australia. Spatial tests were performed at each site, both pooling species, and for each species with >20 individuals. Between 44 and 86% of species were aggregated in natural sites, with pattern in the remainder not distinguishable from random: unexpectedly, the restored sites lay at the upper bound of this variation. Comparison across species groups showed little difference in restored sites, but large differences in natural sites – with aggregation less frequent among large-seeded species, serotinous species and resprouting species. Observed differences among species groups may be attributed to contrasting dispersal mode patterns, spatial heterogeneity associated with fires, and multi- versus single-generational dispersal and these differences in observed patterns may influence future restoration trajectories. Other differences between natural and restored vegetation included a higher incidence of gaps, and lower stem density of restored vegetation. The increased abundance of gaps in restored vegetation suggests a major role of spatial processes in restoration failure.
|Publication Type:||Conference Item|
|Murdoch Affiliation:||School of Environmental Science|
|Item Control Page|