Introduction to the marine environment Flashcards
Metals in the ocean abundance increasing left to right
Mg, Fe, Cr, Cn, Zn, Ni, V, Mo
Why is Fe not found in higher concentrations in ocean water?
Iron is not soluble in water it is usually found as Fe III and therefore precipitates
How organisms cope with low Iron
- Metalloenzymes (e.g. DMS contributes to climate cooling – cloud formation)
- Carbonic anhydrases (from diatoms)
Which elements are limiting factors for algal blooms?
Nitrogen and iron
Where is vanadium (5) haloperoxidase and what does it do?
Helps the release of iodine into the atmosphere – controls cooling
Used as a substitute for iron
How does the enzyme vanadium (5) haloperoxidase control cooling of algae?
Creates a haze (IO.) above the algae by combining with ozone, this also protects the algae from dangerously high concentrations of ozone at lowtide
What is siderophore?
Strongest known soluble iron binding agent
e.g. vibrioferrin
Where is siderophore found?
In bacteria which have an association with the algae
How do you algae utilise vibrioferrin?
Takes Fe2+ from bacteria (which has Fe2+ -> Fe3+ using vibrioferrin)
Where is the permanent thermocline found in ocean?
At 200 to 1000 m
Where is the seasonal thermocline found in the ocean?
In the mid-latitudes at depth of 40 to 100 m
Why is high salinity water in the centre of the main oceans?
Due to ocean gyres causing rotation of current and spinning the denser salty water into a mound within the centres of oceans
What is celerity?
Wavelength or wave period
How do you calculate Wavelength?
1.56 x (wavelength)^2
How high is a wave at the point the wave breaks?
1/7th of a wavelength roughly
What is the equilibrium theory of tides?
Water on Earth moves around a little bit as the Moon moves around the Earth, causing the tides.
What is a neep tide?
When the Earth, moon and sun at 90° angles from each other
What is a spring tide?
When the Sun and the moon on either side of the Earth
What is the ebbtide?
When the tide is going out
What is the floodtide?
When the tide is coming in
What is a pycnocline?
A layer in the ocean at which water density increases rapidly with depth
What is a thermocline?
A layer in the ocean at which temperature decreases rapidly with depth
What are the major subdivisions of the world Ocean horizontally?
Neritic zone (Continental shelf) Oceanic zone (Open ocean)
What are benthic organisms?
Organisms of the seabottom
What are pelagic organisms?
Organisms that live in the open sea away from the bottom
What are the ocean divisions based on light?
Photic 0-200m
Epipelagic 100-200m
Disphotic zone 200-1000m
Aphotic zone >200m
What is the disphotic zone?
Zone where there is not enough light for photosynthesis but enough light for vision
Aphotic zones, defined by depth
Mesopelagic 200 m to 700/1000 m
Bathypelagic from 700/1000 m TO 2000/4000 m
Abyssalpelagic deeper than 2000/4000 m
Hadalpelagic. Greater than 6000 m
Larvae which use the plankton phase mainly for dispersal
Lecithotrophic
Holoplanktonic
Organisms which spend whole lives in the plankton
Meroplanktonic organisms
Spend part of life cycle in the plankton often the larval stage
Three types of larval dispersal
Planktotrophic
Lecithotrophic
Nonpelagic
Two types of larva produced by one type of settling plankton
Standard - locates adults with chemo reception and settles there
Pioneer - seeks new rock or settlement
Differences between terrestrial and marine food webs
Marine show a marked by a mass per metre squared at top of food chain them bottom – Phytoplankton have fast turnover
Investment in offspring lower in marine environment
Microscopic producers and herbivores are dominant group not macroscopic producers e.g. plankton and zooplankton
ocean divisions in pelagic terms
0-200m epipelagic zone
200-1000m mesopelagic zone
1000-4000m bathypelagic
4000-6000m hadalpelagic
Planktotrophic
- pelagic feeding larva in plankton and bottom dwelling invertebrate adults
Lecithotrophic
- pelagic nonfeeding larva in plankton and bottom dwelling invertebrate adults
Nonpelagic
- bottom dwelling invertebrate adults, non-pelagic egg capsule travels p,then settles to form juvenile/adult
what is a polar cell?
cold air sinks and flows south (atmosphere)
what is a ferrel cell?
warm air rises at the polar front and circulates clockwise
what is a hadley cell?
warm, moist air rises from the equator
tropical air carries heat north/south
what is the coriolis effect?
moving object has apparent deflection to;
- right in northern hemisphere
- left in southern hemisphere
stronger effect towards poles, zero effect towards equator
the winds from the north pole to the south pole
1. polar easterlies subpolar low 2. westerlies 3. subtropical high equatorial low 4. subtropical high 5. westerlies subpolar low 6. polar easterlies
what is Ekman spiral?
wind blows surface water in one direction
water beneath surface is deflected to right be decreasing decrees with decreasing power @ depths
