Aquatic info Saltwater: AKA marine. 3.5% salt +35 ppm concentration. Brackish water is less salty than marine, but too salty to be freshwater. Places where.

Aquatic info Aquatic info

Saltwater:  AKA marine.  3.5% salt +35 ppm concentration. 

Brackish water is less salty than marine, but too salty to be freshwater. Places where fresh and salt water meet.

Coastal estuaries, seas, few lakes

Freshwater: less than 1% salt concentration. <35 ppm Rivers, lakes, ponds, streams.

How have fish adapted to fresh and salt water? OSMOSIS REVIEW!!!!!

• Aquatic Life - saltwaterPlankton: drifting or weakly swimming life forms. – Phytoplankton: plant plankton, floating…

important?– Zooplankton: animal plankton, weak swimming

• Ultraplankton: photosynthetic bacteria, microscopic.  May be responsible for 70% of primary productivity at ocean surface.

• Nekton: strong swimming consumers. Fish, turtles, whales

• Benthos/Benthic: bottom dwellers. Oysters, tube worms, lobsters, Crabs.

• Decomposers: mostly bacteria that break down dead organic matter.

Where do they fit?Where do they fit?

Key Characteristics of Key Characteristics of Aquatic EcosystemsAquatic Ecosystems

1. Less pronounced and fixed 1. Less pronounced and fixed boundaries than terrestrial ecosystems.boundaries than terrestrial ecosystems.

2. Longer, more complex food chains2. Longer, more complex food chains

3. Difficult to study and monitor because 3. Difficult to study and monitor because of size and they are hidden from view.of size and they are hidden from view.

4. Life is found in distinct zones or 4. Life is found in distinct zones or layers – surface, middle, bottomlayers – surface, middle, bottom

Limiting Factors for Life Limiting Factors for Life Under waterUnder water

1.1. Temperature – gets colder the deeper the Temperature – gets colder the deeper the waterwater

2.2. 2. Light – gets darker the deeper the 2. Light – gets darker the deeper the waterwater

3.3. 3. Dissolved oxygen content 3. Dissolved oxygen content

4.4. 4. Dissolved nutrients such as 4. Dissolved nutrients such as C, P, and NC, P, and N

5.5. 5. pH5. pHThese are the basic measurements of water qualityThese are the basic measurements of water quality

Oxygen Oxygen

Oxygen Oxygen

a. Enters the system through atmosphere a. Enters the system through atmosphere and photosynthesizing organismsand photosynthesizing organisms

   b. Is depleted by respiration (fish gills)b. Is depleted by respiration (fish gills)

c. Can vary within an ecosystem due to c. Can vary within an ecosystem due to temperature, number of producers, temperature, number of producers, number of decomposers, and circulation number of decomposers, and circulation of waterof water

What about respiration rates of fish, What about respiration rates of fish, DO and temp? DO and temp? Why do some fish seek cooler water?Why do some fish seek cooler water?

• DO in relation DO in relation to depthto depth

• What do you What do you think happens think happens to the diversity to the diversity of critters with of critters with

depth?depth?

DO vs Depth of a lakeDO vs Depth of a lake

DO vs time of the year. Is DO vs time of the year. Is this true for the whole this true for the whole earth?earth?

Oxygen and Carbon DioxideOxygen and Carbon Dioxide

Carbon dioxideCarbon dioxide

a. Enter through atmosphere and a. Enter through atmosphere and respiring organisms.respiring organisms.

b. Can be depleted by photosynthesizing b. Can be depleted by photosynthesizing organisms, organisms using carbonate organisms, organisms using carbonate ions to make shells skeletons, and ions to make shells skeletons, and through sedimentation (rock formation).through sedimentation (rock formation).

c. Carbon sinkc. Carbon sink

Where is the water and life Where is the water and life at?at?

In the Zone! Its deep!• •Euphotic zone: top layer that sunlight

can penetrate.  Pollution, algae, etc, can reduce depth of this zone.  Photosynthesis usually confined to this layer. Higher D.O. levels.

• •Bathyal Zone: second layer down, “twilight” Typically between 200-1500m. Less animal life than euphotic zone. These animals come to the euphotic zone to feed

• •Abyssal zone: Extremely deep, below 1500m Few life forms; little D.O. Strange looking creatures!

Horizontal Zones

• Estuarine zone: places where freshwater meets sea water.  Salt concentrations will vary.

• Coastal Zones: teeming with life. Area above the continental shelf.

• Open sea: area beyond the reach of the continental shelf.

• Intertidal zones: area between high and low tides.

Dark

ness

Tw

ilig

ht

Ph

oto

syn

thesis

Sun

Continental shelf

Estuarine Zone

High tide

Low tide

Coastal

Zone

Bathyal Zone

Euphotic Zone

Abyssal Zone

Sea level

Open Sea

Found Nemo!! YUM!!!!Found Nemo!! YUM!!!!

Nemo’s House

• Coral Reef: typically in warm, coastal marine regions.  Filled with life and biodiversity!

• More than Nemo lives here – 25% of all marine species, 66% of all marine fish species live here.

• Protect about 15% of coastline from erosion by

slowing incoming waves

• In danger: we’ve lost 25% of coral reefs because of coastal development, pollution, overfishing, ocean warming

Coral Reef• Can only form in warm, tropical, shallow oceans

with stabile high salinity.

• Required temps: 18 – 30o C (64-86oF)

• Bleaching can occur at 31o C!

• Affected by: temperature increases, sedimentation, pollution, floods, storms, predatory fish.

• Good news: a growing number of coral reefs are now listed as preserves or protected.

• Artificial reefs…restorationArtificial reefs…restoration

Coastal reefsCoastal reefs

The Great Barrier Reef Aus.The Great Barrier Reef Aus.

Atoll reefs Found in the South Atoll reefs Found in the South Pacific SeaPacific Sea

Bleaching of coralBleaching of coral

Nuke Testing on reefs!Nuke Testing on reefs!

Sunken shipsSunken shipsNavy Scraps ships and Navy Scraps ships and sinks???sinks???

Used tiresUsed tires

Estuaries and Coastal Estuaries and Coastal Wetlands: Wetlands: They’re Productive!They’re Productive!

• Estuaries include Estuaries include river mouths, river mouths, inlets, bays, inlets, bays, sounds, salt sounds, salt marshes in marshes in temperate zones temperate zones and mangrove and mangrove forests in tropical forests in tropical zones.zones.

Mangrove ForestsMangrove Forests• Are found Are found

along about along about 70% of gently 70% of gently sloping sandy sloping sandy and silty and silty coastlines in coastlines in tropical and tropical and subtropical subtropical regions.regions.

Estuaries and Coastal Estuaries and Coastal Wetlands: Wetlands: Centers of ProductivityCenters of Productivity

• Estuaries and coastal marshes provide Estuaries and coastal marshes provide ecological and economic services.ecological and economic services.– Filter toxic pollutants, excess plant Filter toxic pollutants, excess plant

nutrients, sediments, and other pollutants.nutrients, sediments, and other pollutants.– Reduce storm damage by absorbing waves Reduce storm damage by absorbing waves

and storing excess water produced by and storing excess water produced by storms and tsunamis.storms and tsunamis.

– Provide food, habitats and nursery sites for Provide food, habitats and nursery sites for many aquatic species.many aquatic species.

Rocky and Sandy Shores: Rocky and Sandy Shores: Living with the TidesLiving with the Tides

• Organisms experiencing daily low and Organisms experiencing daily low and high tides have evolved a number of high tides have evolved a number of ways to survive under harsh and ways to survive under harsh and changing conditions.changing conditions.– Gravitational pull by moon and sun causes Gravitational pull by moon and sun causes

tides.tides.– Intertidal Zone: area of shoreline between Intertidal Zone: area of shoreline between

low and high tides.low and high tides.

Rocky and Sandy Shores: Rocky and Sandy Shores: Living with the TidesLiving with the Tides

• Organisms in Organisms in intertidal zone intertidal zone develop develop specialized niches specialized niches to deal with daily to deal with daily changes in:changes in:– TemperatureTemperature– SalinitySalinity– Wave actionWave action

Barrier IslandsBarrier Islands

Low, narrow, sandy islands that form Low, narrow, sandy islands that form offshore from a coastline.offshore from a coastline.

• Primary and secondary dunes on gently Primary and secondary dunes on gently sloping sandy barrier beaches protect sloping sandy barrier beaches protect land from erosion by the sea.land from erosion by the sea.

Ocean BeachPrimary

DuneSecondary DuneTrough Back Dune

Bay or Lagoon

Limitedrecreation

and walkways

Intensive recreation,no building

Intensiverecreation

Most suitablefor development

Taller shrubs and treesTaller shrubs

Grasses or

shrubs

No direct passage

or building

No direct passage

or building

No filling

Bay shore

Productivity and Aquatic Productivity and Aquatic Ecosystems Ecosystems

The more light and nutrients available The more light and nutrients available in an ecosystem the more productivein an ecosystem the more productive

Shallow waters with lots of nutrient = Shallow waters with lots of nutrient = high productivity.  high productivity.  

Open ocean = low productivityOpen ocean = low productivity

What about deep ocean?What about deep ocean?