Topic 3: Aquatic Environment Flashcards
The amount of light entering and travelling through water is determined by what 2 main factors?
The amount of surface reflection and The amount of light scattered or absorbed by particles/water molecules
What does turbidity mean?
Basically refers to how much dissolved particles is in something (Turbidity is the measure of relative clarity of a liquid).
Lots of dissolved particles = ⬆️ turbid
Less dissolved particles = ⬇️ turbid
A portion of light is reflected based on 3 factors
- Angle of light
- perpendicular angle = ⬆️ reflection
- oblique angle = ⬇️ reflection
- Varies by time of day
- Seasonality
What is the photic zone?
The photic zone is the region of water that is penetrated by light and is therefore characterized by the presence of plant life, notably phytoplankton and larger attached algae.
What is the “blue-shift”? Why does this occur?
The deeper you get in the ocean the bluer the organisms. This is because there is a change in the quantity and quality of light.
Plants that do photosynthesis are restricted to what area of the water?
-100m
How do organisms that live in the deep ocean survive?
They utilize food sources that filter down from the photic zone. As organisms die, they drop down into the deep oceans.
What kind of bodies of water does stratification occur in?
Stratification can occur in any non flowing or slow flowing body of water
What is meant by productivity?
Measurement of growth of organisms, especially the photosynthetic organisms
Describe why there are lower O2 levels in the hypolimnion VS the epilimnion.
warmer water cannot hold gasses very well. despite the epilimnion having a lower holding capacity than the hypolimnion, the reason the epilimnion holds more O2 is because of production vs depletion. the epilimnion holds less but it regenerates it as well. even though the holding capacity in the hypolimnion is higher, the O2 in the hypolimnion once used does not regenerate.
Why do organisms in shallow bodies of water face struggles with O2 consumption.
Shallow bodies of water heat up during the day and stay warm at night. during the day the plants photosynthesize oxygen but at night plants stop and instead so photorespiration and thus use up the O2, leaving less for the organisms. the O2 levels drop dangerously. fish and other aquatic animals may go to the surface to gulp air.
