Ocean Zones and Marine Ecosystems Notes

2. a. Amount of light
b. Depth
c. Temperature
d. Nutrient availability
e. Density
f. Latitude
g. Distance from shore

3.  Pelagic Zone – water portion
 Benthic Zone – ocean floor

4.  Neritic – from low tide mark to edge of continental
shelf
 Oceanic – Open water beyond continental shelf

5.  Epipelagic/Sunlit Zone – sun reaches through it
 Mesopelagic/Twilight Zone – light not strong enough
to support a lot of life
 Bathypelagic then Abyssalpelagic then Hadalpelagic
(in increasing depth) make up the Midnight Zone
 Photic Zone consists of both the Sunlit (euphotic) and
Twilight (dysphotic) zone
 Aphotic Zone consists of the Bathypelagic,
Abyssalpelagic, and Hadalpelagic zone

6.  Supralittoral – water splashes on but does not become
submerged
 Littoral – intertidal zone, area between low and high
tide
 Sublittoral – remainder of the continental shelf
 Bathyal – continental slope
 Abyssal – deep ocean bottom
 Hadal – deepest zones, trenches

8.  Species – a single organism
 Population – a collection of the same species living in
the same area
 Community – a collection of populations
 Ecosystem – a collection of communities with the
same biotic (living) and abiotic (non-living) factors

9.  Shallow open ocean
 1% of the ocean but a
majority of marine life
 Supports photosynthesis
 Zone most affected by
pollution and global
warming

10.  Neritic zone between the
low tide mark to the edge
of the continental shelf
 High in nutrients due to
upwelling
 High light amounts and
heat retention

11.  Where ocean water
meets rivers in a semi-
enclosed area
 Highly biologically
productive due to
sediment runoff
 Organisms specifically
adapted to deal with
changes in salinity

12.  Located in estuaries and
coasts with shallow
slopes constantly
enriched by tidal
motions
 High salinity due to
evaporation

13.  Swamps in which larger
trees (Mangroves) whose
roots provide an
important safe
environment for juvenile
organisms and protect
shorelines from erosion
due to violent storms

14.  The only place where one
can find true, vascular
plants submerged under
water

15.  Areas such as the
supralittoral zone (only
splashed with water) and
tide pools, have
organisms specially
designed to prevent
drying out

16.  Sandy regions that
protect the shoreline
 Many organisms live
within the sand
 Serves large role in
cleaning the water

17.  Groups of algae that
thrive in cooler, nutrient
rich waters, which in
turn provide an
important source of food
and protection for other
organisms

18.  One of the most diverse
ecosystems on Earth (land
or water)
 Need low nutrient waters
to prevent competitions
with other organisms
 Large amounts of light
needed for photosynthesis
 Affected greatly by global
warming
 High diversity and low
populations of organisms

19.  Extremely nutrient rich
 Drastic changes in
productivity between
summer and winter due
to heat and light
duration
 Low diversity and high
populations, especially
large whales

20.  Nutrients provided by
marine snow (sediment
from dead animals and
fecal matter)
 Makes up most of the
ocean
 Low density of life
 Very little information
about the organisms

21.  When a dead whale
reaches the ocean floor
 Three stages
 Scavengers consume the
soft tissues over a couple
months
 Worms consume the
remaining soft tissues over
a year
 Chemosynthetic bacteria
breaks the remaining
portions down over the
next decade

22.  Chemosynthetic bacteria
convert the released
sulfides
 These bacteria then serve
as the primary base (in
place of producers) of
the deep ocean
ecosystem