BI 423: Temperature Aquatic Ecology Test 1

Most heat is gained from

solar radiation

most heat is lost from

thermal radiation

Most heat gain and loss is at the ____ of water

surface

Most important thermal implication is

thermal stratification

what is thermal stratification

layering of water due to different temperatures

Spring turnover temperature

homogeneous temperature from top to bottom

epilimnion

Warmer, less dense, upper layer

hypolimnion

Colder, more dense, lower layer

metalimnion Area b/w two where greatest temp change w/ depth occurs

Area between hypolimnion and epilimnion where greatest temp change with depth occurs

thermocline

the middle transition layer in a large body of water where the temperature drops fast as depth increases (sharp and distinct)

Fall turnover

cooler, more dense surface H 2 O sinks - Mixes, further cools epilimnion - Eventually H 2O in epilimnion is similar in temp (& density) to hypolimnion - Epi + hypo begin to mix uniformly from top to bottom - = homogeneous temp from top to bottom

winter stratification

inverse stratification occurs, a winter water-layering pattern in lakes where colder, lighter water sits on top of slightly warmer, denser water

spring turnover

As ice melts and surface water warms - So, density differences disappear - Wind mixes water from top to bottom - Surface waters continue rapid heating moving toward summer stratification

Most IR + red absorbed, transformed to

heat in first few meters

Some lakes gain heat by

input, runoff or groundwater temps

Warmer temps =

more density differences

Mixis n. (adj. mictic)

Lake mixing i.e turnover

Amictic

no mixing usually permanent ice cover

meromictic

partial mixing

Lake Nyos in Cameroon in 1986 had ____ eruption

limnic

Holomictic

>1 complete mixing

Dimictic

2 periods of mixing / year; requires winter inverse stratification (ice cover)

Warm monomictic lakes

One period of mixing in the fall/winter

where are warm monomictic lakes common

southern or warm temperate regions

cold monomictic lakes

4 degree C or below with periods of mixing in summer,

where are cold monomictic lakes common

arctic regions, extreme N temperate areas

polymictic lakes

Mix almost continuously & will mix almost daily

cool polymictic lakes

ice-covered part of year - At or slightly above 4oC during warm season. Stratify briefly in heat of day, cool and mix at night

warm polymictic lakes

Tropical lakes with temps > 4oC - short periods of heating & weak stratification followed by rapid cooling - Winds & convection sufficient to break up stratification

temp quiz q 1

temp quiz q 2

temp quiz q 3

temp quiz q 4

temp quiz q 5

temp quiz q 6

temp quiz q 7

temp quiz q 8