Ecology- Lake Stratiication Flashcards
When do lakes stratify?
During summer months from increased solar radiation, with weak summer wind unable to mix the dense cold water beneath.
Why does spring and summer support algal blooms?
As deep-layer nutrients are brought up from the mixing period in the winter and early spring.
Microbial Loop
Models aquatic ecosystems loop food web comprising bacteria, dinoflagellates, ciliates and other zooplankton.
What sunlight do lakes recieve?
Shortwave solar and reflected longwave.
How is stratfication ecologically important?
When stratified, the metalimnion prevents water-column mixing, thus isolating hypolimnion from atmospheric gas exchange
When might the hypolimnion recieve light for photosynthesis?
Clearer lakes allow deeper penetration
Types of lake based on stratification?
Dimictic
Monomictic
Oligomictic
Polymictic
Amictic
Meromictic
Dimictic
Typical of temperate climates where stratification occurs twice a year.
Monomictic
Experience turnover only once a year, thic can be cold or warm.
Oligomictic
Do not stratify every year, found say in low humid and high wind equatorial regions, with little seasonal changes
Polymictic
Stratify and mix throughout ice-free periods in lakes to shallow to thermally stratify.
Amictic
Permanently stratified
Meromictic
Contain eplimnion and metalimnion vertical mixing that does not extend to the hypolimnion.
What happens to incident radiation on water?
Reflected, scattered or absropted.
What does incidence light cause in water bodies?
Stratification
