L2-ocean environments, factors that influence distribution Flashcards
What is the thermocline?
warm water layer that prevents nutrient transport?
What does upwelling cause?
increased supply of nutrients
WHat are causes of upwelling?
oceanic currents (gulf stream)
equatorial upwelling
coastal upwelling
What causes coastal upwelling?
Ekman transport due to winds blowing parallel to coastlines
Where in continents do you typically get upwelling
west side
What does upwelling stimulate?
primary producativity
Rocky shores features?
rare-new or lots of waterflow
dominated by macroalgae
goes from intertidal to 100m
What stresses are associated with rock pools ?
high pH, high salinity, low
nutrient concentrations
Where are phytoplankton found?
Open waters
What lives in soft sediments?
sea grass
benthic microalgae
What are Mangels?
Mangels are communities dominated by mangroves
What is the primary limiter on algae growth?
light
Why might alage want to be in the harsh conditions of intertidal?
light is available
What happens when intertidal algae is exposed?
lose water
can’t take in nutrients
exposed to much higher temperatures
What have many algae evolved to avoid desiccation?
decreased surface area to volume ratio
production of sulphated polysaccharides(agar)
What is the boundary layer?
layer of water on the surface that don’t move. stops nutrient spread as nutrients can only move via diffusion
What do waves do?
decreasing the thickness of the boundary layer
How can waves damage plants?
abrasion
drag
pressure
features of shallow edges?
high productivity environments
1% of ocean floor
well lit
lots of described species
examples-beaches,mangrooves
features of open ocean?
200-250m
most of productivity
lots of light
lots of blue animals as that is what is best for camouflage
features of mesopelagic?
midwater 200m-2km
little studied
sunlight absent
narrow thermocline
features of Abyssal bottom?
no light
•High pressure
•Low temperature
•Few currents
Factors that influence the distribution and abundance of animals in the oceans?
- Physical properties of water
- Light
- Temperature (water is a good heat conductor)
- Pressure
- Oxygen availability
- Salinity
- Nutrients (food)
Why can many organism only see blue?
only light that penetrates water deep
What effects does pressure have on animals?
Structural problem for gas filled spaces
e.g. buoyancy and swim bladders
Could collapse/expand depending on depth - need to
change gas contents with depth
What is o2 content for water breathers in water influenced by?
slow diffusion
Temperature
Biological
Salinity
How does O2 change with temp?
low temp has more water
Where is oxygen lowest?
middle depth of ocean(oxygen minimum zone) due to bacteria eating sinking debris
Why are bioturbators important?
the aerate the sediments
WHere is salinity reduced?
estuaries
WHere is salinity increased?
rockpools, salt marsh, lagoons etc, with
restricted access to tidal flow
