Evaluation of Ecological Theories Through Analysis of Species Richness in a Rocky Intertidal Habitat
Research Mentor(s)
McLaughlin, John
Description
We evaluated two prevailing theories for determinants of species richness, using rocky intertidal habitat as a model system. Mechanistic knowledge about species richness is important to success in biological conservation, restoration, and habitat management. We measured relationships between disturbance regimes and intertidal species richness patterns in Salt Creek Recreation Area, Strait of Juan de Fuca, Washington. We compared these relationships with predictions of the intermediate disturbance vs. facilitation hypotheses. The intermediate disturbance hypothesis predicts species richness peaks at intermediate disturbance frequencies, with habitats restricted to competitive dominants and pioneer species at low and high frequencies respectively. The facilitation hypothesis predicts species richness increases with time since disturbance, as additional species inhabit increasingly complex structures. The two hypotheses also differ in their assertions about the importance of factors structuring ecological communities: the intermediate disturbance hypothesis assumes interspecies competition dominates, while the facilitation hypothesis assumes positive interactions are more important. We sampled algal and invertebrate species richness on randomly selected rocks spanning a range of sizes, which is a surrogate for disturbance frequency. We analyzed relationships between species richness and disturbance frequency using linear and quadratic regression. Our results address one of the fundamental issues in ecological science, and they have important implications for conservation and management in an era of changing natural and anthropogenic disturbance regimes.
Document Type
Event
Start Date
17-5-2018 9:00 AM
End Date
17-5-2018 12:00 PM
Department
Environmental Sciences
Genre/Form
student projects, posters
Subjects – Topical (LCSH)
Environmental impact analysis; Ecology
Type
Image
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this documentation for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Language
English
Format
application/pdf
Evaluation of Ecological Theories Through Analysis of Species Richness in a Rocky Intertidal Habitat
We evaluated two prevailing theories for determinants of species richness, using rocky intertidal habitat as a model system. Mechanistic knowledge about species richness is important to success in biological conservation, restoration, and habitat management. We measured relationships between disturbance regimes and intertidal species richness patterns in Salt Creek Recreation Area, Strait of Juan de Fuca, Washington. We compared these relationships with predictions of the intermediate disturbance vs. facilitation hypotheses. The intermediate disturbance hypothesis predicts species richness peaks at intermediate disturbance frequencies, with habitats restricted to competitive dominants and pioneer species at low and high frequencies respectively. The facilitation hypothesis predicts species richness increases with time since disturbance, as additional species inhabit increasingly complex structures. The two hypotheses also differ in their assertions about the importance of factors structuring ecological communities: the intermediate disturbance hypothesis assumes interspecies competition dominates, while the facilitation hypothesis assumes positive interactions are more important. We sampled algal and invertebrate species richness on randomly selected rocks spanning a range of sizes, which is a surrogate for disturbance frequency. We analyzed relationships between species richness and disturbance frequency using linear and quadratic regression. Our results address one of the fundamental issues in ecological science, and they have important implications for conservation and management in an era of changing natural and anthropogenic disturbance regimes.