Transcript Estuary Notes - West Branch Schools

Estuaries
Coastal Ecosystems
 Highly
productive
Nutrient-rich
Ample sunlight
Shelter
Estuary
 Partially
enclosed water
bodies where fresh and
saltwater mix
 Constant
flushing and
exchange of nutrients
Salt-wedge Estuary
 occurs
when high-salinity seawater from
the ocean slips into the estuary under the
less dense fresh water coming in from the
river
Importance of Estuaries:
 Feeding
ground
 Spawning ground
 Nursery area
 Sediment stabilizer
 Protection from storms
EstuariesVariation
of salinity- affects
distribution of marine life
Very hardy due to the many changes
they must be able to tolerate
Salinity
Oxygen
Temperature
4 Types of Estuaries based on Origin:
1.Coastal plain- sea level rises and floods
existing river valleys(Chesapeake Bay)
2.Fjord-forms as sea level rises and floods
glaciated valley (coasts of Alaska, Canada)
3.Bar-built-shallow and separated from the open
ocean by sand bars deposited parallel to the
coast by wave action (US Gulf Coast)
4.Tectonic-faulting or folding or rocks creates
restricted drowned river valleys
(San Francisco Bay)
Where are these type of organisms
more likely to be found in an
estuary?
 Euryhaline-
Capable of tolerating a wide
range of salt water concentrations; found
down in the estuary
Example:
bull shark
 Stenohaline-animals
are those which are
sensitive to relatively small changes in
salinity; found deeper water and open sea
Florida Shoreline Estuary Communities
consist of:
Mangrove
&
Salt marsh
Distribution of Salt Marsh vs. Mangroves
 Salt
marshes are found along most
U.S. shores
 BUT
 Mangrove swamps are only in limited
areas.
 Where are mangrove swamps limited
too? Tropical climates
Salt Marshes
 Variation
in salinity of a
salt marsh is important in
distribution of marine
plants.
 Most
plants can’t live in
saltwater b/c osmosis
dehydrates them
Organisms in Salt Marsh Community
Worms
Juncus
•Fiddler crabs
Spartina
Mosquitoes
Salt Marsh Zonation
(draw in notes)
Mangroves
Mangrove Swamps
Bigger, tougher than halophytes, &
found in tropical climates
 Red, White, Black mangroves
 Disappearing due to social
pressures
Red, White, and Black Mangrove

Leaves (left to right; topsides)
Red, White, and Black
Mangrove Leaves
(left to right; undersides)
Organisms in Mangrove Community
 Pelicans
and other seabirds
 Mangrove
and fiddler crabs
 Oysters

Mussels
 Many
 Snails
small fish
10.13 Detritus
 Loose
material from the
breakup of organic and
inorganic material
(organic muds, ooze)
 typically includes the
bodies or fragments of
dead organisms as well as
fecal material
 Serves as a food source
for microscopic
organisms
Mangroves are trees
that have the ability to
tolerate salt.
There are 3 different species of
Mangroves in Florida
Red mangroves
1. usually found closest to the salt water.
2. prop and drop roots
3. propagule or pencil—cigar shaped seedlings
which begin to grow on the tree, drop off,
then float in the water until they plant
themselves.
4. leaves large, rounded, thick, and waxy.
Black mangroves
-Form
behind the red
mangroves
-Pneumatophores—slender
upright aerating roots
which stick out of the mud.
-Seeds look like large lima
beans
-Leaves are leathery with
silvery undersides. They
excrete salt on the upper
sides.
-Tallest of the mangroves.
White mangroves
1.
2.
3.
Generally the third
zone from the sea.
Have pneumatophores
but not as many as the
black.
Leaves are rounded
with a “dip” at the tip.
At the base of each leaf
are two bumps which
secrete nectar which
attracts ants for
pollination.
Mangrove Zonation
(draw in notes)
Intertidal
zone
white
black
red