By Helena Nikoguova Coral Reefs. Geography Climate: -Clear, shallow, warm, optimum temp is 24 degrees Celsius -Require a salinity of 33 ppt. Location:

By Helena Nikoguova

Coral Reefs

GeographyClimate:

-Clear, shallow, warm, optimum temp is 24 degrees Celsius

-Require a salinity of 33 ppt.

Location:

-Wider Caribbean (Atlantic Ocean)

-The Indo-Pacific (from East Africa and the Red Sea to the Central Pacific Ocean).

GeographyAvg. Rainfall: Southwest

gets 60 inches per year, differs for each reef.

Sunlight: Needs lots for symbiotic algae to do photosynthesis.

Depth: No deeper than 60-

90 feet. Clean Water: Sensitive to

pollution and sediments.

Seasonal Changes

• Gulf of Maine:– Winter: less phytoplankton (less sunlight,

mixing of ocean layers)– Spring: more phytoplankton (more nutrients

washed in, more sunlight)– Summer: less phytoplankton (it gets eaten)– Fall: second phytoplankton increase (increased

water overturning)

Seasonal Changes• Caribbean Sea:

– Almost no variation of phytoplankton concentrations occurs in most areas

– Amazon River Nutrients and other

runoff washed into thesea after the rainy season

Phytoplankton bloom-ing increases

Limiting Factors

• Space

• Water temperature (currents) [68 to 82F]

• Depth and light amount [<150 ft]

• Salinity [30 to 40 parts per thousand]

• Runoff and Sedimentation

• Water movement (oxygen, nutrients, larvae)

Animal Life

Coral Polyps Parrotfish

Damselfish Hawksbill Turtle

Animal Life

Jellyfish Cleaner Shrimp

Sea Krait (Snake) Red-knobbed Seat Star

Vegetation

Blue-green algae (cyanobacteria)

Red algae

Brown algae Coralline algae

Vegetation

Calcareous algae Turtle grass

Manatee grass Shoal grass

Animal Adaptations

Toxins: Makes unappetizing to deter predators; compete for space.

Symbiosis: Corals have a mutualistic relationship with zooxanthellae.

Schooling: Fish traveling with large group during day, and dispersing when senses a predator.

Animal Adaptations

Nocturnal: Ex. Caribbean Spiny Lobsters

-Hunt at night = safer from eagle rays, sharks.

Color/Camouflage: Ex. Flounder Fish

-Looks like sand on reef

floor.

Plant Adaptations

• Seagrasses + rhizomes (underground creeping stems)– Anchoring– Filtering– Preventing beach

erosion

Plant Adaptations

• Calcification– Neptune’s Shaving

Brush– prevents grazing– makes plant harder to

digest /uproot

• Chemicals– Ceramium sp. – Chemical production

alters taste to make them unappealing to herbivores

Food Web

Human Pressures• Nearly 1/3 of 704 species are endangered, or on the verge.

• Mass bleaching in 1998 wiped out 16% of all reefs.

• In last decade, much deterioration caused by humans, natural disasters, climate changes.

• Sea surface temperature + ocean acidity have risen

(acidification from carbon dioxide).

Human Pressures and Activities

• Overfishing (ecosystem imbalance)• Pollution

– Organic: soil runoff (algal blooms), windborne, sewage, mines

– Non-organic: chemical fertilizers, oil, other factory outlet chemicals, radioactive wastes

• Global warming– Sea level rise, temperature

increase: coral bleaching, coral diseases

Human Pressures and Activities

• Ocean acidification – Increased CO2+water=carbonic acid=pH

drop=reduced calcification

• Coral mining (coral rocks used for cement)

• Loss of mangrove forests and seagrasses

• Fishing boat damage, mooring, building construction

Conservation Techniques

• Many programs use plant propagation• Marine Protected Areas (MPAs)

– Fishery management– Habitat protection

• Electrochemical techniques– Adding white carbonate (aragonite)– Inhibiting algal bloom growth– Mineral accretion (artificial reef surfaces)

Conservation Techniques

• Reducing greenhouse gas emissions

• Artificially placing hermatype coral onto substrate

• Restoring sections of broken reef with concrete

• Reef balls