Marine Ecology

Question 0

Why are mangrove forests difficult environments for organisms to live in?

Answer 0

• Low oxygen
• High and variable salinity
• High temperature & water loss

Question 1

What are mangrove forests?

Answer 1

Tropical, sheltered depositional coastal environments e.g. estuaries or inlets (but are not restricted to only estuaries). They are characterised by mangroves, the woody trees or shrubs adapted to saline environments.

Question 2

What are the 4 key genera in mangrove forests?

Answer 2

Red Mangrove (Rhizophora)
White mangrove (Laguncularia)
Black mangrove (Avicennia)
Mangrove apple (Sonneratia)

Question 3

What are the types of continental shelves?

Answer 3

a – Soft bottomed benthic

b – Seagrass beds

c – Hard bottomed benthic

d - Kelp forests

Question 4

Discuss and contrast the physiological adaptations of (i) mesopelagic and (ii) deeper-zone organisms, relating to light.

Answer 4

Write l8rrr

Question 5

Turtle Migrations

Answer 5

•Marine turtles spend most of their lives at sea, returning to land to lay eggs.
•Natal homing
•
•Research on nesting green turtles on Mayotte suggests turtles navigate using geomagnetic cues - Turtles were displaced, and satellite tracked. Longer homing paths when magnets put on head.

Question 6

What is phenology?

Answer 6

Timing of life history events in organisms

Question 7

Properties of water

Answer 7

Commonly found as liquid, gas and solid
Covalent
Polar
Hydrogen bonds - gives water unusually high melting and boiling point
Good solvent - dissolves more substances in greater quantities than any other liquid (salts, sugars, acids, and some gases)
Salts dissolve better at high temps
Gases dissolve better at low temps

Question 8

Light penetration in water

Answer 8

Visible light attenuates with depth
Extreme wavelengths lost first: red and violet
Blue travels furthest down water column

Question 9

Ocean depth profiles

Answer 9

Temperature: surface layer is warmest. Thermocline (colder with increasing depth) past surface layer to 1,000m. Constant temp in deep layer.
Density: surface layer has lowest density. Pycnocline (increased density with increasing depth) past surface layer to 1,000m. Constant density in deep layer.
Salinity: differs in intermediate and surface layer, constant in deep layer.

Question 10

Seasonality in Ocean depth profiles

Answer 10

Summer: bigger difference between surface and deep temp. Surface is warmer
Autumn: surface water cools and becomes denser and sinks - downwelling. Displaces deeper water which then rises - overturn
Winter: this continues - water from deep and surface mixes.

Question 11

Coriolis effect

Answer 11

Affects ocean circulation
Currents and winds are deflected:
To the RIGHT in the northern hemisphere
To the LEFT in the southern hemisphere 
By the Coriolis effect

Question 12

Major gyres

Answer 12

North Pacific gyre
North Atlantic gyre
Indian Ocean gyre
South Pacific gyre
South Atlantic gyre