Vegetation Dynamics in an Experimentally Fragmented Landscape

摘要: In spatially heterogeneous habitats, plant community change may reflect localized population-level processes that are sensitive to the size of an average habitat patch. However, local species turnover can also be determined by initial conditions and large-scale processes, in which case patch effects overridden. To examine role directing secondary succession, we subdivided a newly abandoned agricultural field into array experimental patches (32, 288, 5000 m2, grouped sample equivalent portions field), have thereafter censused resident animal communities at regular intervals. Here report results from first 6 yr studies on changing vascular experimentally fragmented land- scape. The general course all followed trajectory typical old-field toward increasing dominance longer lived larger species. same group dominated start study continued dominate after yr, although very different proportional abundances. Larger were more rich than their smaller counterparts, had higher proportion nonshared species, but additional transient low abundance. Spatial heterogeneity vegetation, measured as dissimilarity, increased lesser extent largest patches, where censuses nearby permanent quadrats indicated less diver- gence over time. At population level, strongest effect was populations clonal prone disappear smallest patches. Nevertheless, summary measures temporal did not significant differences turnover. We conclude does markedly affect rate or pattern early scales imposed our experiment.