Chapter_14_Section_3

Document Sample
Chapter_14_Section_3 Powered By Docstoc
					                       Earth Science
                        Chapter 14
                         Section 3

A. Conditions of the Neritic Zone:

  Horizontal zone of the ocean.

  Intertidal Zone- stretches from the highest high-tide line on
  the land out to the point on the continental shelf exposed by
  the lowest low tide.

  Neritic Zone- the part of the ocean that extends from the
  low-tide line out to the edge of the continental shelf.

  Open-Ocean Zone- beyond the edge of the continental shelf.

  The shallow water over the continental shelf receives
  sunlight and a steady supply of nutrients washed from the
  land into the ocean.

  The light and nutrients enable large plantlike algae, such as
  the giant kelp to grow.

  These algae serve as a food source and shelter for other
  organisms.

  In parts of the neritic zone, nutrients from upwelling supports
  plankton, which increases fish population - good for fishing
  and the ocean food web.

  Two diverse habitats typically found in the neritic zone.
  1. Kelp forests
  2. Coral reefs
  Kelp Forests

  Grow in neritic waters
  They are large and heavy algae
  They require a solid rocky bottom to anchor their stalks
  A bundle of root-like strands called a holdfast attach the
  algae to the rocks.
  A stalk of Giant Kelp can grow to 30 meters in length.
  Kelp produce food through photosynthesis.
  Provide a habitat for many organisms.
  Sea urchins can wipe out a kelp forest if not kept under
  control by sea otters that eat them.
  Once thriving kelp forests can become a barren rocky zone.

  Coral reefs

  Coral reefs are found in warm, shallow waters.
  They are formed by groups of tiny coral animals that produce
  a hard material around their soft bodies.
  When the animals die the hard material is left behind.
  Over time the hard remains create a coral reef.
  Organism like the octopuses, spiny lobsters, shrimp, moray
  eels and colorful fish live among the reefs.


B. Conditions in the Open Ocean:

Two Zones are identified in the open ocean.
    1. Surface Zone
    2. Deep Zone
  The surface zone is the only part of the open ocean that
  receives enough sunlight to support the growth of algae.

  These microscopic algae are the base for the open ocean food
  web.


  In the deep zone, there is no sunlight. Finding food in the
  deep zone darkness is a challenge. Many deep sea fishes
  produce their own light.

  The production of light by living things is called
  bioluminescence.

  Some organisms use chemical reactions to produce light,
  others have light-producing organs and some have
  bioluminescent bacteria living in their bodies.

C. Hydrothermal Vents:

A hydrothermal vent is an area where ocean water sinks through
cracks in the ocean floor, is heated by magma and rises again
through cracks.

These vents are located along ocean ridges where new ocean
floor is being created.

The heated water coming from a vent carries gases and minerals
from Earth’s interior.

The chemical nutrients in the heated water support the unique
group of organisms that are found around hydrothermal vents.

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:1
posted:12/18/2011
language:
pages:3