Aquatic Ecology Aquatic Ecology NotesNotes

Photic ZonePhotic Zone

Aphotic ZoneAphotic Zone

Intertidal ZoneIntertidal Zone

Coral ReefCoral Reef

Life in LayersLife in Layers

Life in most aquatic systems is found Life in most aquatic systems is found in surface, middle, and bottom layers.in surface, middle, and bottom layers.

Temperature, access to sunlight for Temperature, access to sunlight for photosynthesis, dissolved oxygen photosynthesis, dissolved oxygen content, nutrient availability changes content, nutrient availability changes with depth.with depth. Euphotic zone (upper layer in deep water Euphotic zone (upper layer in deep water

habitats): sunlight can penetrate.habitats): sunlight can penetrate.

Lakes: Water-Filled Lakes: Water-Filled DepressionsDepressions

Lakes are large natural bodies of standing Lakes are large natural bodies of standing freshwater formed from precipitation, runoff, freshwater formed from precipitation, runoff, and groundwater seepage consisting of:and groundwater seepage consisting of: Littoral zoneLittoral zone (near shore, shallow, with rooted (near shore, shallow, with rooted

plants).plants). Limnetic zoneLimnetic zone (open, offshore area, sunlit). (open, offshore area, sunlit). Profundal zoneProfundal zone (deep, open water, too dark for (deep, open water, too dark for

photosynthesis).photosynthesis). Benthic zoneBenthic zone (bottom of lake, nourished by dead (bottom of lake, nourished by dead

matter).matter).

Littoral ZoneLittoral ZoneA shallow area near the shore, to the A shallow area near the shore, to the

depth at which rooted plants stop depth at which rooted plants stop growing. Ex. frogs, snails, insects, growing. Ex. frogs, snails, insects, fish, cattails, and water lilies.fish, cattails, and water lilies.

Limnetic ZoneLimnetic Zone

Open, sunlit water that extends Open, sunlit water that extends to the depth penetrated by to the depth penetrated by sunlight.sunlight.

Profundal ZoneProfundal ZoneDeep, open water where it Deep, open water where it

is too dark for is too dark for photosynthesis.photosynthesis.

Lakes: Water-Filled Lakes: Water-Filled DepressionsDepressions

Figure 6-15Figure 6-15

OligotrophicOligotrophic

EutrophicEutrophic

Freshwater Freshwater WetlandsWetlands

Freshwater Inland Wetlands: Freshwater Inland Wetlands: Vital SpongesVital Sponges

Inland wetlands Inland wetlands act like natural act like natural sponges that sponges that absorb and absorb and store excess store excess water from water from storms and storms and provide a provide a variety of variety of wildlife wildlife habitats.habitats. Figure 6-18Figure 6-18

Freshwater Inland Wetlands: Freshwater Inland Wetlands: Vital SpongesVital Sponges Filter and degrade pollutants.Filter and degrade pollutants. Reduce flooding and erosion by Reduce flooding and erosion by

absorbing slowly releasing overflows.absorbing slowly releasing overflows. Help replenish stream flows during dry Help replenish stream flows during dry

periods.periods. Help recharge ground aquifers.Help recharge ground aquifers. Provide economic resources and Provide economic resources and

recreation.recreation.

MarshesMarshesAn area of temporarily flooded, An area of temporarily flooded,

often silty land beside a river or often silty land beside a river or lake.lake.

SwampsSwampsA lowland region permanently A lowland region permanently

covered with water.covered with water.

Importance of freshwater Importance of freshwater wetlandswetlands

They filter & purify water.They filter & purify water.Habitat for many animals Habitat for many animals

and plants.and plants.

Historical AspectsHistorical Aspects

Developers and farmers want Developers and farmers want Congress to revise the definition of Congress to revise the definition of wetlands. This would make 60-75% of wetlands. This would make 60-75% of all wetlands unavailable for all wetlands unavailable for protection. The Audubon Society protection. The Audubon Society estimates that wetlands provide water estimates that wetlands provide water quality protection worth $1.6 billion quality protection worth $1.6 billion per year, and they say if wetlands are per year, and they say if wetlands are destroyed, the U.S. would spend $7.7 destroyed, the U.S. would spend $7.7 billion to $31 billion per year in billion to $31 billion per year in additional flood-control costs.additional flood-control costs.

EstuariesEstuaries

DefinitionDefinitionA partially enclosed area of A partially enclosed area of

coastal water where sea water coastal water where sea water mixes with freshwater.mixes with freshwater.

Salt MarshesSalt Marshes The ground here is saturated with water The ground here is saturated with water

and there is little oxygen, so decay takes and there is little oxygen, so decay takes place slowly. It has a surface inlet and place slowly. It has a surface inlet and outlet, and contains many invertebrates. outlet, and contains many invertebrates. It is also the breeding ground for many It is also the breeding ground for many ocean animals. Ex. crabs and shellfish.ocean animals. Ex. crabs and shellfish.

Mangrove ForestsMangrove Forests These are along warm, These are along warm,

tropical coasts where tropical coasts where there is too much silt for there is too much silt for coral reefs to grow. It is coral reefs to grow. It is dominated by salt-tolerant dominated by salt-tolerant trees called mangroves trees called mangroves (55 different species (55 different species exist). It also helps to exist). It also helps to protect the coastline from protect the coastline from erosion and provides a erosion and provides a breeding nursery for some breeding nursery for some 2000 species of fish, 2000 species of fish, invertebrates, and plants.invertebrates, and plants.

                                  

Importance of EstuariesImportance of Estuaries

Just one acre of estuary provides Just one acre of estuary provides $75,000 worth of free waste treatment, $75,000 worth of free waste treatment, and has a value of about $83,000 when and has a value of about $83,000 when recreation and fish for food are included. recreation and fish for food are included.

Prime Kansas farmland has a top value Prime Kansas farmland has a top value of $1,200 and an annual production of $1,200 and an annual production value of $600.value of $600.