Transcript Marine Ecosystems

AQUATIC LIFE ZONES:
SALTWATER (MARINE) Ecosystems: Estuaries, coastlines,
coral reefs, coastal marshes, mangrove swamps, continental
shelf, & deep ocean
AQUATIC Ecosystems: Lakes and Ponds, Streams and
Rivers, and Inland wetlands
TYPES OF ORGANISMS:
Plankton – free floating (or weak swimmers)
(phytoplankton – primary producers & zooplankton – primary consumers)
Nekton – strong swimmers (fish, turtles, whales)
Benthos – bottom dwellers (oysters, barnacles, crustacean, worms)
Decomposers – mostly bacteria
SALINITY &
TEMPERATURE
DETERMINE THE
DISTRIBUTION OF
THE OCEANIC
REALMS
Physical & Chemical Characteristics
Water provides buoyancy = physical
support, reduces the need for large
supporting structures of trunks and
legs, helps aquatic organisms move
vertically
Water provides consistency = keeps
organism from drying out or
requiring water, constant
temperature range
Water provides readily dissolved
nutrients – b/c water is the universal
solvent the nutrients are ready for
uptake by primary producers
Adaptations for Floating
Water provides constant flux – like
wind terrestrially, water gives
constant circulation and disperses
organisms and their larvae & dilutes
toxins
Primary Productivity
No primary producers
– many organisms rise
to the euphotic zone at
night to feed
Abyssal
Very little nutrients
(marine snow) ~250, 000
named organisms
Coastal zone makes up only <10% of
the ocean and contains 90% of all
marine organisms
Diversity of organisms in each layer is
determined by: 1) temp 2) sunlight
3) dissolved oxygen 4) nutrients
(dissolved CO2 to from carbonate ions
for shells), nitrates, phosphates
ESTUARIES/Salt Marsh
Ecological and Economic Benefits
 Partially enclosed area of
coastal water where
freshwater & silt from rivers
meets the sea.
 High productive area
 Temperature & Salinity vary
daily rhythms of the tides,
seasonally with river input
fluctuations, and with
unpredictable storms
Chesapeake Bay
BAYS, SOUNDS, & INLETS
 Serves as a breeding ground
form any organisms
(waterfowl, marine organisms)
 Filtrates sediments, excess
nutrients and pollutants
 Acts as a buffer to inland
areas during storms
Lie along the coast line in
estuaries and intertidal
communities of the tropics
and subtropics.
Mangroves provide habitat form
many organisms & reduce long
term beach erosion
Act as a filtering system –
especially for heavy metals that
settle into the anoxic soil below
Adaptations to live in anoxic / nutrient
poor soil; marine water conditions; &
limited supply of freshwater
 Leaves secrete excess salts
 Pneumatophores –”roots” for
uptake of gases
DUNE SYSTEMS
Vegetation is
crucial for the
success of the
dune system
Construction & Development
should ideally be behind the
secondary dune system
Economically dunes are
important in the reduction of
storm surge damage to coastal
development
Barrier Island Systems
Helps protect main land
development.
Also protects coastal dunes
& estuary systems.
CORAL REEF DYNAMICS
• Most biologically diverse
aquatic system (niche
availability)
• Three categories of organisms
1) sessile – attached organisms
2) borrowing organisms
3) fishes
• Live between 18°C to 30°C
(even one degree above that
can trigger bleaching)
Photomicrograph of algae
clusters in coral polyp
Coral Reefs exist in low nutrient
waters (oligotrophic) and therefore
rely on an endosymbiotic algae
(zooxanthellae) to provide
nutrients
 Ecosystem that survives without sunlight!
 Primary producers = chemosynthetic bacteria
 Bacteria use sulfur compound to synthesize energy
 Clams & Tubeworms either eat bacteria or harbor
them in their body to supply themselves with “food”