Intro to marine bio Flashcards
Which boat did we do our trip on?
John Strickland
Pelagic
in the water column
benthic
on or in the bottom
neritic or coastal
< 200m deep
oceanic or “open ocean”
> 200m deep
How much marine life lives in the top 200m of the ocean (the epipelagic zone)?
90%
where does life at the lower/bottom parts of the ocean get its nutrients?
things falling from upper layers (death)
Areas of super high productivity:
west coast of south america, california, and africa
How much (%) of the global fish does the 4.5% of the ocean that is super productive account for?
50% of fish!
Which population is more open/connected?
terrestrial or marine
marine
marine primary production can vary alot more than terrestrial because:
primary producers in marine ecosystems are very tiny, short-lived. so….
marine primary producers are easier to eat directly, carbon moves through system faster, short-term environmental fluctuations can have significant effects on energy production in food chain
“Classic” marine foodchain
diatoms –> copepods –> larval fish
keystone species are
species that have a larger role in the overall productivity of the ecosystem
example of trophic levels:
phytoplankton → herbivorous zooplankton → carnivorous zooplankton → zooplanktivorous fish
Trophic pyramid
- used by ecologists to follow the flow of energy from one trophic level to the next
- relative size of each layer represents the relative biomass of organisms in that trophic level
the amount of energy available to higher trophic levels depends on three factors
- amount of primary production
- trophic transfer efficiency
- number of trophic levels
What is trophic transfer efficiency?
efficiency by which energy is transferred from one trophic level to the next
What is the equation for trophic transfer efficiency?
(Production in trophic level looking at divided by production in trophic level below) x 100 = %
Where does energy go that isn’t transferred to higher trophic level?
- feces
- respiration
- dies uneated
