Ecology: Lecture 3 Flashcards
What are some examples of aquatic biomes?
Freshwater, estuaries, and marine biomes.
What are estuaries?
they form a barrier between the freshwater systems (rivers) and the marine systems (the ocean).
How do aquatic biomes vary with salinity?
Freshwater has low salinity
Estuaries are med. salinity
Marine has high salinity
What does salinity effect?
Osmoregulation:
- The level of salt in the body
- It can be a big challenge and change the structure of the biomes.
Salinity does what to biomes and how?
Salinity is. factor that structures biomes, separating freshwater from marine biomes.
- It affects physiological systems and other systems.
Examples of animals being in multiple habitats/biomes?
Bull sharks (marine) to rivers
Salmon (freshwater) to marine
Depth is what kind of factor?
Depth is an important structuring factor in the ocean.
What does depth affect?
Depth affects:
- Light levels (deeper = darker)
- Temperature (deeper = colder)
- Pressure
How much light is gone below 200m?
99% of light is gone below 200m.
Different zones of the ocean - distance to shore?
Intertidal: Sometimes exposed to air and other times exposed to water
Neritic: Nearshore
Offshore: Oceanic zone
Different zones of the ocean - depth?
Photic zone: sunlight and photosynthesis occur here. 0-200
Aphotic zone: darker, no photosynthesis occurs here. 200-2000
Mesopelagic zone: 200-1000m deep, the twilight zone
Abyssal zone: Very dark, still som penetration of light. 2000-6000m
Pelagic Zone vs. Benthic Zone?
Pelagic Zone: the water column
Benthic Zone: things are attached here, the “sea floor”
What happens daily?
A large migration daily for marine animals to feed. They come up the water column then down again.
Why do so many feeders swarm skeletons on the bottom?
There is no photosynthesis down:
- Deep sea is therefore limited in food and most productivity occurs much higher up.
- Therefore, when a large amount of food comes down, there is an aggregation of organisms that come to feed.
Benthic vs Pelagic?
seafloor vs water column
photic vs. aphotic?
sunlight vs. no light
Intertidal vs. Neritic vs. oceanic?
shoreline, coastline area, offshore
Zoning in lakes?
Similar zoning!
Distance from shore in lakes?
Littoral zone = air and water depending on the day
Limnetic zone = farther out
Depth in lakes?
Photic = light reaches
Aphotic = no light can reach
Other zones in lakes?
Pelagic = water column
Benthic = lake floor
What is stratification?
How fixed the water column is
What does stratification in lakes control?
Nutrients can be a limiting factor, one thing controlling nutrient availability is stratification.
- It tends to have nutrients circulate by waters mixing vertically.
- Could be stratified (layers that don’t mix).
What is a thermocline?
A thermocline is a zone of rapid temperature change.
- This means that you have a gradient in temperature throughout the water (warm on top of hot).