Marine Ecology

1
Marine Ecology
2
Ecology is the study of the inter-relationships
between the physical and biological aspects of
the environment. It is the study of how organisms
adapt to their environment and in turn alter it.
3
(No Transcript)
4
There are two major marine provinces the
benthonic (bottom) and the pelagic (water column).
9-1
Ocean Habitats

• The benthonic environment is divided by depth
  into the Intertidal zone, Sublittoral zone,
  Bathyal zone, Abyssal zone, and the Hadal zone
• The pelagic environment is divided into the
  Neritic Zone and the Oceanic Zone

5
Ocean Habitats
6
The ocean can also be divided into zones based
upon depth of light penetration.
9-1
Ocean Habitats

• The photic zone is the depth where light is
  sufficient for photosynthesis.
• The dysphotic zone is where illumination is too
  weak for photosynthesis.
• The aphotic zone receives no light from the
  surface because it is all absorbed by the water
  above.

7
Marine organisms can also be classified by
lifestyle.
9-3
Classification of Lifestyle

• Plankton are the organisms which float in the
  water and have no ability to propel themselves
  against a current.
• They can be divided into phytoplankton (plants)
  and zooplankton (animals).
• Nekton are active swimmers and include marine
  fish, reptiles, mammals, birds and others.
• Benthos are the organisms which live on the
  bottom (epifauna) or within the bottom sediments
  (infauna).
• Some organisms cross from one lifestyle to
  another during their life, being pelagic early in
  life and benthonic later.

8
(No Transcript)
9
(No Transcript)
10
Benthic community - kelp bed
11
(No Transcript)
12
In 1735 Linnaeus developed the taxonomic
classification used in zoology.
9-2
Classification of Organisms

• The categories are from largest to smallest
  Kingdom, Phylum, Class, Order, Family, Genus and
  Species.
• The name of a species consists of the genus name
  combined with a trivial name.
• The genus name begins with a capital.

13
The five major kingdoms in the ocean are Monera,
Protista, Fungi, Metaphyta and Metazoa.
9-2
Classification of Organisms

• Monera are the bacteria and blue-green algae.
• Protista are single-celled organisms with a
  nucleus.
• Fungi are abundant in the intertidal zone and are
  important in decomposition.
• Metaphyta are the plants that grow attached to
  the sea floor.
• Metazoa include all multicellular animals in the
  ocean.

14
Environmental factors in the marine environment
include temperature, salinity, pressure,
nutrients, dissolved gases, currents, light,
suspended sediments, substrate (bottom material),
river inflow, tides and waves.
9-4
Basic Ecology

• Ecosystem is the total environment including the
  biota (all living organisms) and non-living
  physical and chemical aspects.
• Temperature can control distribution, degree of
  activity and reproduction of an organism.
• Salinity can control the distribution of
  organisms and force them to migrate in response
  to changes in salinity.

15
More than 90 of marine plants are algae and most
are unicellular and microscopic.
9-5
Selective Adaptive Strategies

• To photosynthesize (produce organic material from
  inorganic matter and sunlight) plants must remain
  within the photic zone.
• Diatoms are single cells enclosed in a siliceous
  frustrule (shell) that is shaped as a pillbox.
• Dinoflagellates are single cells with two
  whip-like tails (flagella).

16
Land vs. Ocean Plants
17
Phytoplankton Maximize Surface Area
18
Diatoms
19
Zooplankton include the copepods and foraminifera.
9-5
Selective Adaptive Strategies

• Copepods are small herbivores (plant-eating
  organisms) that filter diatoms from the water.
• Foraminifera are single-celled, microscopic
  organisms which build shells of calcium carbonate.

20
Zooplankton - Copepods
21
Intertidal benthonic communities generally
display vertical zonation that parallels sea
level.
9-5
Selective Adaptive Strategies

• Zonation reflects the amount of time the area is
  submerged and the ability of the organism to
  survive the stress of exposure.
• Benthonic communities also vary in response to
  substrate (bottom material).

22
Rocky intertidal - vertical zonation
23
9-4
Basic Ecology

• Hydrostatic pressure is the pressures exerted by
  a column of water surrounding an organism.

24
The morphology of fish has evolved to allow them
to move through the water easily.
9-5
Selective Adaptive Strategies

• The fishs body must overcome three types of drag
  (resistance) Surface drag, Form drag, and
  Turbulent drag.
• Speed is dependent upon body length, beat
  frequency, and the aspect ratio of the caudal
  fin.
• Aspect ratio is the ratio of the square of the
  caudal fin height to caudal fin area AR
  (Caudal Fin Height)2/Caudal Fin Area
• There are three basic body forms, each adapted to
  a different life style.
• There is a strong correlation between predation
  success and body form.