Community dynamics of prairie grasshoppers subjected to periodic fire: predictable trajectories or random walks in time?

TitleCommunity dynamics of prairie grasshoppers subjected to periodic fire: predictable trajectories or random walks in time?
Publication TypeJournal Article
Year of Publication1988
AuthorsEvans, EW
JournalOikos
Volume52
Pagination283 -292
Accession NumberKNZ00173
Keywordstallgrass prairie
Abstract

Grasshopper communities were sampled by sweep net at six sites in native tallgrass prairie at Konza Prairie, Kansas, USA, in 1982-86 to assess community change from year to year in prairie burned once every four years. Species richness, diversity, and composition of grasshoppers did not vary in regular fashion with the four-year fire cycle. Furthermore, the ratio of grass- to forb-feeding grasshoppers generally did not change consistently during the fire cycle at individual sites, although for all sites combined, the relative abundance of grass feeders initially increased after a fire and subsequently declined in succeeding years without fire. Observed year to year changes in grasshopper communities were tested against those predicted by a random walk model of community change using ordination (DCA) results for species composition at individual sites in individual years. This analysis revealed that local communities varied in restricted, compensatory fashion such that they tended to return towards some central or characteristic species composition when displaced. Thus while fire itself imparts relatively little predictability to grasshopper community dynamics in periodically unburned prairie, such dynamics are nevertheless to a limited degree predictable

DOI10.2307/3565201