Abiotic nature of lake ecosystems L.4 Flashcards
What key abiotic factors govern life in freshwater lakes?
- Temperature - seasonal thermal stratification
- Light
- Wind & water movements - Langmuir rotations & Seiches
What sub-habitats do lakes have?
- Littoral
- Pelagic
- Profundal
- Benthic
Whats retention time?
When nutrients are retained for long or short periods of time.
How many lakes are there in Ireland?
Over 12,000
Wheres the litoral zone?
Shallow waters.
Light reaches the bottom.
Where’s the pelagic zone?
Open waters.
Extends to how far light penetrates the water.
Where’s the profundal zone?
Beyond the depth of where light penetrates.
Dark & cold
Where’s the benthic zone.
Bottom region of the lake.
Where decomposition happens.
What lives in the littoral zone.
Stimulâtes growth of primary producers.
What lives in the pelagic zone.
Microscopic plankton
Zooplankton
Fish
What’s the layer of dense cooler water called?
Hypolimnion layer.
What’s the upper warm, less dense layer of water called?
Epilimnion.
Where’s the compensation depth.
Between the photic and aphotic zones.
What are Poikilothermic organisms?
Organisms that regulate their internal temperature to match their surrounding environment.
During seasonal thermal stratification how does the thermocline act?
It acts as a physical barrier preventing mixing of the upper and lower layers
