Albert Zheng Keystone College

Introduction Kelps can grow over 40m in some places. Resembles submarine forests. Example: Coast of California Coral Reefs are diverse in colors. Resembles gardens Example: Coast of Egypt

Geography Marine environment and its inhabitants vary with latitude. In temperate to subpolor regions: Enormous amount of kelp growth The closer you go towards the equator region, the kelp will slowly be replace by coral reefs. Corals are confined to low latitudes, 30°N and 30°S.

Coral Reef Distribution Kelp Forest Distribution Kelps grow along rocky shores in regions with max H2O temperature is < 20°C Corals are absent from shores and grow in H20 temperature averaging about 23°C to 25°C along the equator

Structure In 1842, Charles Darwin was the 1 st to place coral reefs into 3 categories Fringing reefs – are along the shores of the continent or island Barrier reefs – stretches for nearly 2000km off the coast Coral Atolls – consist of coral that have built up from a submerged oceanic island. Atolls Barrier reefs Fringing reefs

Structure Kelp forests, mainly the larger kelps, have structural features similar to terrestrial forests. On the surface of the water is canopy, which can be 25m above seafloor. Stems or stipes of kelps extend from canopy to the bottom and the anchoring to the ground is called holdfast.

Physical Condition Light Both kelp and reef building corals grow only to the surface water where there is enough light to support photosynthesis. Light penetration can be read from a few meters to almost 100m, sufficient enough to support the kelp and coral Varies with local conditions. Temperature Kelps are limited to temperate shores. Corals are restricted to warm waters averaging 23°C to 25°C

Water Movement Coral reefs and kelp beds are continuously being washed by ocean currents that will deliver oxygen and nutrients and remove waste product. However extreme strong currents and waves can detach entire kelp forests and flatten coral reefs.

Chemical Conditions Salinity Coral reefs grow only in stable salinity H2O Kelp beds appear to be more tolerant in fresh H2O runoffs and will grow well along temperate shores. Oxygen Coral reefs and kelp beds occur where water is well oxygenated.

Biology Coral reefs face intense biological disturbances Outbreaks of predatory crown-of-thorn sea star, will eat corals which has devastated large area of coral reefs in the Indo-Pacific region. The center of diversity for reef building corals is in the western pacific and eastern Indian Ocean 600 coral species and over 2000 species of fishes can be found

Biology In a Caribbean coral reef community, population of sea urchin, Diadema antillarum will eat both algae and corals. But these urchins benefit the corals by reducing algal population that will compete for space with the young corals