Unit 3: Marine Ecosystems

Aquatic

Relating to water.

Marine

Of, found in, produced by the sea.

Lentic

Organism or habitat situated in slow-moving or still fresh water.

Lotic 

Organism or habitat situated in rapidly moving fresh water.

Limnology

The study of the biological, chemical, and physical features of lakes and other bodies of fresh water.

Temporary Ponds

Vernal, when snow melts in a forest or low-lying space, is primary for mosquitoes and fairy shrimp. 

Springs

Ponds/Streams, water seeps from earth. 

Geothermal Pools

Really hot springs; algae and bacteria can live at high temperatures.

Caldera

Extinct volcano; deepest lake in the US. 

Tectonic

Result of geologic block faulting; landscape drops and fills with water.

Glacial (Kettle)

When glaciers melt and retreat they grind up underneath, space left fills with water over time.

Lake temperature during winter?

0 on surface 4 everywhere else.

Lake temperature during summer? 

28 on top, 8 in middle, 4 at bottom. 

Lake temperature during fall and spring?

4 all the way through.

Littoral Zone

Shallow area of lake or ocean along the shore.

Limnetic Zone

Open water area of lake or ocean where light can penetrate.

Epilimnion

Sunlight penetrates and warms water. 

Metalimnion

Temperature and other physical and chemical factors change rapidly with depth.

Hypolimnion

Water is cold and dark and may lack dissolved oxygen.

Dimictic

Lake mixes twice a year.

Profundal

Deep water with little to no light.

Benthic

Bottom-dwelling.

Primary Producers (Limnetic) 

Phytoplankton 

Compensation Depth

Where photosynthesis = respiration

Primary Consumers (Limnetic)

Zooplankton

Epilimnion (Limnetic)

Source for a lot of biological material in the lake.

Hypolimnion (Limnetic) 

Sink for much of this material; decomposition. 

Oligotrophic

Nutrient poor; very clear; EX: Lake Taho.

Oligotrophic Characteristics

Little shore vegetation, low concentration of nutrients and phytoplankton, sparse fish, steep shorelines, sand and gravel on bottom.

Eutrophic

High nutrient lake, and highly productive. 

Eutrophic Characteristics

Lots of vegetation on shore, high concentration of nutrients and phytoplankton, gentle shoreline slope, silt, sand, clay bottom, and dense fish population. 

Dystrophic

Neither end; bogs; many carnivorous plants; little nutrients.

Nuisance Algae Blooms

Can make Lake Erie unswimmable because of toxins; solution to add herbicides or zooplankton (biomanipulation)