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We studied the disturbance associated with prairie vole burrows and its effects on grassland plant diversity at the patch
(1 m2) and metacommunity (>5 ha) scales. We expected vole burrows to increase patch-scale plant species diversity by locally reducing
competition for resources or creating niche opportunities that increase the presence of fugitive species. At the metacommunity
scale, we expected burrows to increase resource heterogeneity and have a community composition distinct from the matrix. We
measured resource variables and plant community composition in 30 paired plots representing disturbed burrows and undisturbed
matrix patches in a cool-season grassland. Vole disturbance affected the mean values of nine resource variables measured and
contributed more to resource heterogeneity in the metacommunity than matrix plots. Disturbance increased local plant species
richness, metacommunity evenness, and the presence and abundance of fugitive species. To learn more about the contribution
of burrow and matrix habitats to metacommunity diversity, we compared community similarity among burrow and matrix plots.
Using Sorenson’s similarity index, which considers only presence–absence data, we found no difference in community similarity
among burrows and matrix plots. Using a proportional similarity index, which considers both presence–absence and relative
abundance data, we found low community similarity among burrows. Burrows appeared to shift the identity of dominant species
away from the species dominant in the matrix. They also allowed subordinate species to persist in higher abundances. The patterns
we observed are consistent with several diversity-maintaining mechanisms, including a successional mosaic and alternative
successional trajectories. We also found evidence that prairie voles may be ecosystem engineers. 相似文献
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