coral reefs

what are aphermatypic?

non reef building

what are hermatypic corals?

reef-building

where are hermatypic corals found?

tropics

what are characteristics of tropical coral reefs?

many fish species, more vertebrate species than rainforest, fragile, high biodiversity, complex

reef growth is influenced by…

temperatures

what is the general temp of reefs?

18-36 c

what is the optimal temp of reefs?

26-28 c

what is needed for reefs?

clear, warm water, lots of light, little nutrients

how do reefs develop?

polyps will settle in substratum that meets requirments

how do atoll reefs form?

volcanic island→fringe reef→barrier reef→atoll

what is a back reef?

an area that slopes into a lagoon

what is a reef flat?

on the sheltered side of the reef

what is the reef crest?

the highest point of the reef

what are the characteristics of the reef crest?

high wave energy, coralline algae, wave surge zones

what is the forereef?

part of reef that slopes towards the sea

what are characteristics of hermatypic coral?

colonial, CaCO3 deposited from skeleton, have symbiotic algae/zooplankton

what is the benefit of symbiosis for coral?

increase growth and reproduction, waste removal, facilitates CaCO3 formation, amino acids, carbon supply, nutrient retention, ect.

what is the benefit of symbiosis for alga?

CO2, NH3, PO4, protects from UV damage, high density of single genotype

what is the coral morphology?

bunch of polyps grouped together

what are boulder corals?

more flat

what are branching corals?

branch like a tree

how do corals feed plankton at night?

nemotocysts

how do corals asexual reproduction?

division or budding

how do most stony corals sexually reproduce?

brooding, broadcast spawners

what is the coral life cycle?

brooding, larva, late larva, young polyp, adult polyp

reef growth is kept in check by ____

bioerosion

what is the primary producer in reefs?

zooxanthellae, benthic algae, phytoplankton

most energy is …

recycled within the ecosystem

coral reefs have ____

high rates of primary production

coral reefs are very _____ ecosystems

diverse

where is coral reef species richness the highest?

indo-pacific

what are reefs important for?

food, income, costal defenses, tourism

what is coral reef decline?

decline in coral cover, loss of large vertebrates, increases macro algal cover

what can cause coral reef decline?

over-exploitation of fish and invertebrates

what are threats to coral reefs?

crown of thorns starfish, overfishing, pollution- nutrient and sediment, disease, storms, warming ocean

what is coral bleaching?

When water is too warm, corals will expel the algae (zooxanthellae) living in their tissues causing the coral to turn completely white