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Explore the potential mechanisms impacting the diversity of benthic ecosystems in rocky subtidal habitats of Galapagos Islands, including physical disturbances, sediment structure, turbulence, bioturbation, larval settling dynamics, competition, and predation. Learn how rocky outcrops differ from sediments and influence organism attachment, feeding behaviors, and overall local diversity. Discover major components of vertical and horizontal surfaces, as well as key processes affecting diversity such as predation, competition, spreading, larval settling dynamics, and disturbance dynamics. Delve into the concept of alternate stable states for ecosystems.
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Rocky subtidal habitats A sticky business
Review: Potential mechanisms influencing diversity in benthic ecosystems • Physical processes (disturbance) • Sediment structure • Turbulence • Biological processes • Bioturbation • Larval settling, timing • Competition • Predation
Rocky outcrops differ from sediments • Allows firm attachment of organisms • Much less burrowing into substrate • Turbulence affects attached organisms, less influence on the substrate • Feeding from surfaces and water column • Fewer places to hide • Surfaces often are 100% occupied • High local diversity
Major components of vertical walls:fleshy algaecoralline algaecolonial animals ascidians gorgonianscrustaceansspongespolychaete wormscnidarians
Major processes affecting diversity • Predation • e.g., exclosure experiments on urchins • Competition • access to currents for feeding (overtopping) • Spreading and interference • Larval settling dynamics (priority) • Disturbance dynamics • “random events” create openings • colonization probability varies with time