Importance of Importance of the Ocean the Ocean EnvironmentEnvironment

Marine EcologyMarine Ecology

AreaArea

Saltwater covers about 71% Saltwater covers about 71% of the earth’s surfaceof the earth’s surface

Life:There are 250,000 known species of marine plants and animals, many are food for other organisms, like us.

TemperatureTemperature

Solar heat is distributed by ocean Solar heat is distributed by ocean currents & as ocean water evaporates. currents & as ocean water evaporates.

The oceans are major players in the The oceans are major players in the earth’s climate & are a gigantic earth’s climate & are a gigantic reservoir for carbon dioxide; therefore reservoir for carbon dioxide; therefore they help regulate the temp. of the they help regulate the temp. of the tropospheretroposphere..

Zones of the Zones of the Marine Marine EnvironmentEnvironment

Two major zones that Two major zones that break up into smaller break up into smaller

zones – coastal and the zones – coastal and the open seaopen sea

Intertidal or Intertidal or Beach ZoneBeach Zone

Broken up into five Broken up into five areasareas

Lower ShorefaceLower ShorefaceThe deepest part of the The deepest part of the

beach; farther into the beach; farther into the water, before the breaker water, before the breaker bar that forms wavesbar that forms waves

Upper ShorefaceUpper ShorefaceShallow zone where the Shallow zone where the

waves begin to formwaves begin to form

ForebeachForebeachContains the swash zone – Contains the swash zone –

place where the waves place where the waves crash.crash.

BackbeachBackbeachOnly under water during high Only under water during high

tidetide

Fore-Island DunesFore-Island DunesSand dunes; doesn't flood often, Sand dunes; doesn't flood often,

except during hurricanes, etc. except during hurricanes, etc. Constantly changing due to the Constantly changing due to the windwind

EstuaryEstuary

Where fresh water and Where fresh water and salt water meetsalt water meet

An estuary is a coastal body of water, partly surrounded by land, with access to the open ocean and a large supply of fresh water from a river

CharacteristicsCharacteristics

SalinitySalinity

Salinity fluctuates with tidal Salinity fluctuates with tidal cycles, the time of year, & cycles, the time of year, & precipitation. The organisms precipitation. The organisms that live here must be able to that live here must be able to tolerate these conditionstolerate these conditions

Fertility of EstuariesFertility of Estuaries

Estuaries are the most fertile Estuaries are the most fertile ecosystems in the worldecosystems in the world

Greater productivity than Greater productivity than either the adjacent ocean or either the adjacent ocean or the fresh water upriverthe fresh water upriver

Reasons for High FertilityReasons for High Fertility

Nutrients are transported from the Nutrients are transported from the land into rivers that flow into the land into rivers that flow into the estuaryestuary

Tidal action circulates nutrients and Tidal action circulates nutrients and helps remove wasteshelps remove wastes

A high level of light due to shallow A high level of light due to shallow waterwater

Many plants provide an extensive Many plants provide an extensive photosynthetic carpetphotosynthetic carpet

DifficultiesDifficulties Sandy beach – Life must deal with a Sandy beach – Life must deal with a

shifting environment that threatens to shifting environment that threatens to engulf them & no protection against wave engulf them & no protection against wave action. Most animals bury into the sand. action. Most animals bury into the sand. They move with the tides, so they’re They move with the tides, so they’re always underwater & don’t dry out. always underwater & don’t dry out.

Difficulties (Continued)Difficulties (Continued) Rocky shore – high Rocky shore – high wave action at high tide; wave action at high tide;

drying out & temperature changes during drying out & temperature changes during low. Animals have a way of sealing in low. Animals have a way of sealing in moisture like a shell & find a way to cling moisture like a shell & find a way to cling to the rocks so they don’t get washed away to the rocks so they don’t get washed away with waves.with waves.

PelagicPelagic

The open ocean environment; The open ocean environment; divided into neritic (open divided into neritic (open ocean from the shoreline to a ocean from the shoreline to a depth of 200m) and oceanic depth of 200m) and oceanic provinces (depths > 200m).provinces (depths > 200m).

The Open Ocean

Euphotic ZoneEuphotic Zone

Lots of light. Lots of light. From 0 - 200 From 0 - 200 meters. meters. PhotosynthesPhotosynthesis takes is takes place here.place here.

Bathyal ZoneBathyal Zone

The dimly lit The dimly lit part of part of ocean. From ocean. From 200 - 1500 200 - 1500 meters.meters.

Benthic Characteristics (ocean Benthic Characteristics (ocean floor)floor)

The ocean floor consists of sediments The ocean floor consists of sediments (mostly sand and mud) (mostly sand and mud)

Many marine animals, like worms Many marine animals, like worms and clams, burrow and clams, burrow

Bacteria are common & can go down Bacteria are common & can go down 500 meters below ocean floor. The 500 meters below ocean floor. The Benthic environment extends from Benthic environment extends from the shore to the deep.the shore to the deep.

Sea Grass BedsSea Grass Beds

Flowering plants that have Flowering plants that have adapted to complete submersion adapted to complete submersion in salty water.in salty water.

Location of sea grassLocation of sea grass

Found in shallow water to Found in shallow water to depths of 10 meters where depths of 10 meters where they can photosynthesize. Sea they can photosynthesize. Sea grasses are found in quiet, grasses are found in quiet, temperate, tropical, and temperate, tropical, and subtropical waters; not in polar subtropical waters; not in polar waters.waters.

Eel, turtle, and manatee grass.Eel, turtle, and manatee grass.ExamplesExamples

Ecological ImportanceEcological Importance

Reduce surface erosion, provide Reduce surface erosion, provide food, & provide habitats for food, & provide habitats for many marine organisms.many marine organisms.

Animals that eat sea grass are Animals that eat sea grass are manatees, green turtles, manatees, green turtles, parrotfish, sturgeon fish, and parrotfish, sturgeon fish, and sea urchins.sea urchins.

Abyssal ZoneAbyssal Zone

Completely dark. Completely dark. Extends to a Extends to a depth of 4000 to depth of 4000 to 6000 meters (2.5 6000 meters (2.5 to 3.7 miles). to 3.7 miles). Water here is Water here is very cold & has very cold & has little dissolved little dissolved oxygen.oxygen.

KelpKelp

The largest of the brown algae, many The largest of the brown algae, many reach lengths of 60 meters (200 feet). reach lengths of 60 meters (200 feet). Common in cooler water & are found Common in cooler water & are found along rocky coasts. Provide habitat for along rocky coasts. Provide habitat for many animals like tubeworms, sponges, many animals like tubeworms, sponges, clams, fish, & mammals. Some animals clams, fish, & mammals. Some animals eat the kelp.eat the kelp.

CharacteristicsCharacteristics Built from layers of calcium carbonate, Built from layers of calcium carbonate,

coral reefs are found in warm, shallow sea coral reefs are found in warm, shallow sea water. The living portions must grow in water. The living portions must grow in shallow waters where light hits. They are shallow waters where light hits. They are the most diverse of all marine ecosystems.the most diverse of all marine ecosystems.

Coral ReefsCoral Reefs

ExamplesExamples Many coral reefs are made of red coralline Many coral reefs are made of red coralline

algae that photosynthesize. algae that photosynthesize. Others have zooxanthellae (symbiotic algae) Others have zooxanthellae (symbiotic algae)

that live and photosynthesize in their that live and photosynthesize in their tissues. tissues.

Not all corals have zooxanthellae, but only Not all corals have zooxanthellae, but only those with it build reefs. those with it build reefs.

Coral animals also capture food at night with Coral animals also capture food at night with stinging tentacles that paralyze zooplankton stinging tentacles that paralyze zooplankton and small animals that drift nearby.and small animals that drift nearby.

Coral Reef WatersCoral Reef Waters

The waters where coral reefs The waters where coral reefs are found are often poor in are found are often poor in nutrients. Yet, other factors nutrients. Yet, other factors are favorable such as are favorable such as temperature, sunlight year temperature, sunlight year round, and zooxanthellae.round, and zooxanthellae.

GrowthGrowth

Coral reefs grow slowly; as Coral reefs grow slowly; as one dies, another organism one dies, another organism grows on it.grows on it.

Fringing ReefFringing Reef

The most common type of The most common type of coral reef. It is directly coral reef. It is directly attached to the shore of a attached to the shore of a volcanic island or continent.volcanic island or continent.

Types of Coral Reefs

                                                                                         

Fringing Reef Bora Bora NASA JPL Satellite: Space Shuttle Sensor: SIR-C/X-SAR

AtollAtoll

A circular reef that surrounds a A circular reef that surrounds a central lagoon of quiet water. central lagoon of quiet water.

An atoll forms on top of the An atoll forms on top of the cone of a submerged volcanic cone of a submerged volcanic island. island.

More than 300 atolls are found More than 300 atolls are found in the Pacific and Indian Oceans.in the Pacific and Indian Oceans.

                          View of Midway Atoll from Space Shuttle

                                                                           

Atolls in The Maldives Landsat 7

Barrier ReefBarrier Reef

A lagoon of open water A lagoon of open water separates the land from the separates the land from the barrier reef. barrier reef.

The largest barrier reef is the The largest barrier reef is the Great Barrier Reef off the coast Great Barrier Reef off the coast of Australia. of Australia.

The second largest is off the The second largest is off the coast of Belize.coast of Belize.

Provides a HabitatProvides a HabitatProvides a habitat for a Provides a habitat for a

wide variety of marine wide variety of marine organisms.organisms.

Ecological Importance Ecological Importance of Coral Reefsof Coral Reefs

Coastline ProtectionCoastline Protection

Protects coasts from Protects coasts from shoreline erosion.shoreline erosion.

Benefits for HumansBenefits for Humans

Provides humans with Provides humans with seafood, pharmaceuticals, seafood, pharmaceuticals, and recreational/tourism and recreational/tourism dollarsdollars

Coral Reef RisksCoral Reef Risks

Of the 109 countries with large Of the 109 countries with large reefs, 90 are damaging them, reefs, 90 are damaging them, and 27% of the coral reefs are at and 27% of the coral reefs are at high risk, especially off the coast high risk, especially off the coast of Southeastern Asia.of Southeastern Asia.

In the western Atlantic, 30-50% In the western Atlantic, 30-50% of all coral species are either of all coral species are either rare or endangered.rare or endangered.

Coral Reef Risks Con’tCoral Reef Risks Con’t

Silt washing from downstream has Silt washing from downstream has smothered the reefssmothered the reefs

High salinity from fresh water High salinity from fresh water diversion, over-fishing, boat diversion, over-fishing, boat groundings, fishing with dynamite or groundings, fishing with dynamite or cyanide, hurricane damage, disease, cyanide, hurricane damage, disease, coral bleaching, land reclamation, coral bleaching, land reclamation, tourism, and the mining of coral for tourism, and the mining of coral for building materials.building materials.

                                                             

©1997-2001 Jeffrey N. Jeffords 

This bottle still shows a slightly burned fuse from its use to blow up the coral.

Protection ofProtection of

300 coral reefs in 65 countries 300 coral reefs in 65 countries are protected as reserves or are protected as reserves or parks, and another 600 have parks, and another 600 have been recommended for been recommended for protection.protection.

The good news is coral reefs The good news is coral reefs can often recover from damage.can often recover from damage.