Introduction to Marine Biology: Coral Reefs

These flashcards summarize key concepts related to coral reefs as discussed in the lecture on Marine Biology.

What defines a coral reef?

Coral reefs are biogenic structures deposited by living coral organisms, consisting of colonies formed by individual polyps.

What are the main types of coral reefs?

Fringing reefs, patch reefs, barrier reefs, and atolls.

Where are coral reefs predominantly found?

They are mainly found within a band 30° north and south of the equator.

What factors limit the distribution of coral reefs?

Temperature, depth, sedimentation, salinity, wave action, and air exposure.

What is the significance of zooxanthellae in coral reefs?

Zooxanthellae are algae living symbiotically in coral tissues, crucial for coral nutrition and promoting calcification.

What is Darwin's Subsidence Theory?

It explains the formation of atolls through the stages of fringing reefs, barrier reefs, and eventually atolls surrounding a central lagoon.

Why are coral reefs so productive despite nutrient-poor waters?

Coral reefs have very large plant biomass and effective recycling of nutrients, which boosts primary production.

What role do herbivorous fish play in coral reef ecosystems?

They graze on algae, which helps maintain the health of coral reefs and enhances productivity.

What are some threats to coral reefs?

Climate change, overfishing, pollution, habitat destruction, and invasive species like the crown-of-thorns starfish.

How does structural complexity contribute to fish diversity in coral reefs?

Higher structural complexity provides more niches for species to inhabit, leading to greater diversity.