Aquatic Ecology Quiz 3 (Lakes and Ponds Chapter)

Lake

An encircled body of water if outflow is present at all is very minimal compared to it’s volume.

Lentic System

Minimal movement in body of water (also known as standing water). Made by heating and cooling. Seasonal variation and sunlight also changes temperature in the lakes.

Main abiotic influences in lakes

Water Level:

• Precipitation

• Depression in topography

Bedrock vs Sediments

Bedrock is composed of just rocks. Sediments are a mixture of sand, dirt, etc.

Bedrocks change via

Tectonic activity, volcanic activity, meteor crashes.

Sediments change via

erosion/fluvial flow

Organism that create lakes

Beavers

Barrier lakes

Created via accidents

Monomictic

Single season of mixing (during winter)

Dimictic

Two seasons of mixing

Polymictic

Stratify during the day. Mixes overnight

oligomictic

occasional mixing

amictic

no mixing at all

Typology/topography of lakes

Depression in bedrock

Depression in sediments

Barrie Lakes

Biologically created lakes

Endorheic

enclosed basin

Exorheic

Open Basin

What are the 3 distinct ways lakes are categorized

Typology/topography

Endorheic vs Exorheic

Source of water

Source of waters for rivers

precipitation, streams/rivers, groundwater

Headwater

The top of the river. Only has outflow

lowland drainage

Has both inflow and outflow

Impoundment

Dams

Naturally formed sources of water

seepage, headwater drainage and lowland drainage

Artificially formed sources of water

Impoundment: Dams

Thermocline

Temperature gradient

Thermal stratification

Distinct boundaries or layers caused by different temperatures.

Epilimnion

Top layer of thermal stratification

Metalimnion

Middle layer of thermal stratification

Hypolimnion

Lowest layer of thermal stratification

5 types of climates

Polar, continental, temperate, tropical, dry

What influences the types of climate?

Altitude, angle, rotation

effects of abiotic environment

Light intensity, nutrient stratification, vertical mixing within epilimnion, salinity

light intensity

humic concentration

Eutrophication

the over-enrichment of water by nutrients (mainly nitrogen and phosphorus), leading to excessive algal blooms, severe oxygen depletion (hypoxia), and "dead zones" where aquatic life cannot survive

planktivores

fishes that eat plankton

Piscivores

Fishes that eat other fish