Chapter 7: Pelagic Ecosystem

Question 1

Define Pelagic

Answer 1

• unbounded environment in which the inhabitants have freedom
• the largest habitat on earth
• patchiness in physical properties, biological production, and biomass exists at a range of scales in space

Question 2

What is the difference btwn neritic and oceanic?

Answer 2

N: adjacent to shore
O: out beyond the continental shelf break

Question 3

Describe the Neustic zone

Answer 3

“Floaters”
Neuston-organisms that live at the surface but remain underwater
Pleuston-organisms that live at the sea surface, with part of the body exposed to air

Question 4

what are the zones again?

Answer 4

Neustic (coastal)
epipelagic (0-200, photic)
mesopelagic (1000)
bathypelagic (4000)
abyssopelagic (6000
hadalpelagic (10000)
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littoral, sublittoral, bathyal, abyssal hadal

Question 5

Meroplankton

Answer 5

temporary.

-larval stage of invertebrates and fishes that spend only part of their lives in the zooplankton

Question 6

Holoplankton

Answer 6

permanent:

-spending whole life as a plankton (krill)

Question 7

don’t forget that diel migration is huge for the pelagic system

Answer 7

ok

Question 8

Nekton

Answer 8

the aggregate of actively swimming aquatic organisms in a body of water, able to move independently of water currents.

Question 9

name some ways in which the pelagic zone is ‘patchy’

Answer 9

• micro patches
• swarms
• upwelling
• eddies and rings
• island effects
• el nino type events
• small ocean basins
• biogeographical provinces
• currents and ocean fronts
• currents
• oceanic fronts

Question 10

name some vertical gradients

Answer 10

salinity, temp, density, current velocity, nutrient concentration

Question 11

what are some methods for sampling the open ocean?

Answer 11

• Nets
• CTD conductivity temp density
• OPC optical particle counters
• Echo- microlayers
• by air
• satellites
• AUV - autonomous underwater vehicles