Importance of the Ocean Environment Marine Ecology

Area Saltwater covers about 71% of the earth’s surface Saltwater covers about 71% of the earth’s surface Life: There are 250,000 known species of marine plants and animals, many are food for other organisms, like us.

Temperature Solar heat is distributed by ocean currents & as ocean water evaporates. Solar heat is distributed by ocean currents & as ocean water evaporates. The oceans are major players in the earth’s climate & are a gigantic reservoir for carbon dioxide; therefore they help regulate the temp. of the troposphere. The oceans are major players in the earth’s climate & are a gigantic reservoir for carbon dioxide; therefore they help regulate the temp. of the troposphere.

Zones of the Marine Environment Two major zones that break up into smaller zones – coastal and the open sea

Intertidal or Beach Zone Broken up into five areas

Lower Shoreface The deepest part of the beach; farther into the water, before the breaker bar that forms waves The deepest part of the beach; farther into the water, before the breaker bar that forms waves

Upper Shoreface Shallow zone where the waves begin to form Shallow zone where the waves begin to form

Forebeach Contains the swash zone – place where the waves crash. Contains the swash zone – place where the waves crash.

Backbeach Only under water during high tide Only under water during high tide

Fore-Island Dunes Sand dunes; doesn't flood often, except during hurricanes, etc. Constantly changing due to the wind Sand dunes; doesn't flood often, except during hurricanes, etc. Constantly changing due to the wind

Estuary Where fresh water and salt 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

Characteristics

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

Fertility of Estuaries Estuaries are the most fertile ecosystems in the world Estuaries are the most fertile ecosystems in the world Greater productivity than either the adjacent ocean or the fresh water upriver Greater productivity than either the adjacent ocean or the fresh water upriver

Reasons for High Fertility Nutrients are transported from the land into rivers that flow into the estuary Nutrients are transported from the land into rivers that flow into the estuary Tidal action circulates nutrients and helps remove wastes Tidal action circulates nutrients and helps remove wastes A high level of light due to shallow water A high level of light due to shallow water Many plants provide an extensive photosynthetic carpet Many plants provide an extensive photosynthetic carpet

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

Difficulties (Continued) Rocky shore – high wave action at high tide; drying out & temperature changes during low. Animals have a way of sealing in moisture like a shell & find a way to cling to the rocks so they don’t get washed away with waves. Rocky shore – high wave action at high tide; drying out & temperature changes during low. Animals have a way of sealing in moisture like a shell & find a way to cling to the rocks so they don’t get washed away with waves.

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

Euphotic Zone Lots of light. From meters. Photosynthesis takes place here. Lots of light. From meters. Photosynthesis takes place here.

Bathyal Zone The dimly lit part of ocean. From meters. The dimly lit part of ocean. From meters.

Benthic Characteristics (ocean floor) The ocean floor consists of sediments (mostly sand and mud) The ocean floor consists of sediments (mostly sand and mud) Many marine animals, like worms and clams, burrow Many marine animals, like worms and clams, burrow Bacteria are common & can go down 500 meters below ocean floor. The Benthic environment extends from the shore to the deep. Bacteria are common & can go down 500 meters below ocean floor. The Benthic environment extends from the shore to the deep.

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

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

Ecological Importance Reduce surface erosion, provide food, & provide habitats for many marine organisms. Reduce surface erosion, provide food, & provide habitats for many marine organisms. Animals that eat sea grass are manatees, green turtles, parrotfish, sturgeon fish, and sea urchins. Animals that eat sea grass are manatees, green turtles, parrotfish, sturgeon fish, and sea urchins.

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

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

Characteristics Built from layers of calcium carbonate, coral reefs are found in warm, shallow sea water. The living portions must grow in shallow waters where light hits. They are the most diverse of all marine ecosystems. Built from layers of calcium carbonate, coral reefs are found in warm, shallow sea water. The living portions must grow in shallow waters where light hits. They are the most diverse of all marine ecosystems. Coral Reefs

Examples Many coral reefs are made of red coralline algae that photosynthesize. Many coral reefs are made of red coralline algae that photosynthesize. Others have zooxanthellae (symbiotic algae) that live and photosynthesize in their tissues. Others have zooxanthellae (symbiotic algae) that live and photosynthesize in their tissues. Not all corals have zooxanthellae, but only those with it build reefs. Not all corals have zooxanthellae, but only those with it build reefs. Coral animals also capture food at night with stinging tentacles that paralyze zooplankton and small animals that drift nearby. Coral animals also capture food at night with stinging tentacles that paralyze zooplankton and small animals that drift nearby.

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

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

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

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

Atoll A circular reef that surrounds a central lagoon of quiet water. A circular reef that surrounds a central lagoon of quiet water. An atoll forms on top of the cone of a submerged volcanic island. An atoll forms on top of the cone of a submerged volcanic island. More than 300 atolls are found in the Pacific and Indian Oceans. More than 300 atolls are found in the Pacific and Indian Oceans.

View of Midway Atoll from Space Shuttle

Atolls in The Maldives Landsat 7

Barrier Reef A lagoon of open water separates the land from the barrier reef. A lagoon of open water separates the land from the barrier reef. The largest barrier reef is the Great Barrier Reef off the coast of Australia. The largest barrier reef is the Great Barrier Reef off the coast of Australia. The second largest is off the coast of Belize. The second largest is off the coast of Belize.

Provides a Habitat Provides a habitat for a wide variety of marine organisms. Provides a habitat for a wide variety of marine organisms. Ecological Importance of Coral Reefs

Coastline Protection Protects coasts from shoreline erosion. Protects coasts from shoreline erosion.

Benefits for Humans Provides humans with seafood, pharmaceuticals, and recreational/tourism dollars Provides humans with seafood, pharmaceuticals, and recreational/tourism dollars

Coral Reef Risks Of the 109 countries with large reefs, 90 are damaging them, and 27% of the coral reefs are at high risk, especially off the coast of Southeastern Asia. Of the 109 countries with large reefs, 90 are damaging them, and 27% of the coral reefs are at high risk, especially off the coast of Southeastern Asia. In the western Atlantic, 30-50% of all coral species are either rare or endangered. In the western Atlantic, 30-50% of all coral species are either rare or endangered.

Coral Reef Risks Con’t Silt washing from downstream has smothered the reefs Silt washing from downstream has smothered the reefs High salinity from fresh water diversion, over-fishing, boat groundings, fishing with dynamite or cyanide, hurricane damage, disease, coral bleaching, land reclamation, tourism, and the mining of coral for building materials. High salinity from fresh water diversion, over-fishing, boat groundings, fishing with dynamite or cyanide, hurricane damage, disease, coral bleaching, land reclamation, tourism, and the mining of coral for building materials.

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

Protection of 300 coral reefs in 65 countries are protected as reserves or parks, and another 600 have been recommended for protection. 300 coral reefs in 65 countries are protected as reserves or parks, and another 600 have been recommended for protection. The good news is coral reefs can often recover from damage. The good news is coral reefs can often recover from damage.