Document: THO-3-52-44

Community persistence at different temporal intervals independent of spatial location.

THERRIAULT, T.W.*

McMaster University, Hamilton, ON, Canada ¹

Abstract:
The relationship among aquatic communities within a restricted geographical area is examined over different temporal intervals. By evaluating the relationship among pool communities over time rather than the relationship between pool communities at distinct times, a different pattern of temporal dynamics emerges. Environmental variability is suggested as a contributing factor in temporal patterns of community persistence. Community patterns were evaluated using invertebrate communities collected from 13 freshwater Jamaican rock pools at time intervals of 2 weeks, 6 months, and 1 to 8 years. Calculating the absolute difference in Jaccard's Similarity Index (JSI), Sorenson's Similarity Index (SSI), the complemented coefficient of community (CD), and the number of common species between pool-pairs, over different time intervals, assessed community persistence independently of spatial location. The absolute difference in SSI and CD were smallest for the shortest temporal interval, 2 weeks, but the other measures of persistence were not statistically significant. However, when environmental differences among pools were included in the analyses, the absolute difference in SSI and JSI were smallest for the shortest temporal interval. In general, there was a negative relationship among absolute differences in community metrics and differences in pool conditions (i.e. temperature or salinity). Results showed that biotic determinants might be more important for determining the persistence of communities than environmental variables, especially in a tropical system.

Keywords: invertebrates, aquatic, persistence, temporal scale

This abstract is being presented at: 1:30 PM in session:
Oral Session #47: Zooplankton Ecology.