estuaries: communities
TRANSCRIPT
Benitez, Ezel Anne R.
Dizon, Jhulien C.
Bernardino, Mark Adrian P.Estuaries as Ecosystems
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open WaterMudflatsSalt MarshesMangrove ForestsOther Estuarine Communities
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open WaterLots of suspended sediment → murky water → poor light penetration → limited primary production by phytoplankton
Small estuaries – planktons are flushed in and out
Large estuaries – have own estuarine species
Good nurseries for fish and invertebratesAbundant food
Fewer predators
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open Water
The Atlantic Menhaden (Brevoortia tyrannus)
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open Water
yellow-eyed mulletflatfish
anchovies
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open WaterSome organisms move through estuaries during migration
Anadromous Fishes - migrate from the sea to spawn in fresh water.
Salmon Smelt Shad
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open WaterSome organisms move through estuaries during migration
Catadromous Fishes - migrate from fresh water to spawn at sea.
European eelLong-fin eel
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Open WaterFew spend entire lives in estuaries
Killifish ( Fundulus )
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsBottoms of estuaries that are exposed at low tides
Extensive in large tidal range
Sand - accumulate near river mouth & tidal creeks
Fine, silty – in calmer central part of mudflat
Low tides expose organisms to dessication, temperature change, & predation
Regular variations in salinity
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPrimary producers: not usually evident
EnteromorphaSea lettuce (Ulva)
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPrimary producers:
Diatoms forming golden-brown patches
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPrimary producers:
Bacteria decompose organic matter
Production of H₂S by some bacteria
H₂S is used by sulfur bacteria to produce energy
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsInfauna
Most dominant
Burrow on sediments
Feed on detritus
EpifaunaLive on sediment
Some are sessile
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsMeiofauna
A.k.a interstitial animals
Most are deposit feeders
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsDeposit feeders – eat organic materials in sediments
Suspension feeders – feed on suspended materials in water
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Mudflats
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPredators:“Resource
Partitioning”
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPredators:
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
MudflatsPredators:
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshTemperate and sub-arctic regions
Partially flooded at high tide
Salt / tidal marshes
In N. Hemisphere, more extensive on the left side
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt Marsh: Communities are dominated by grasses & land plants
A salt marsh near Atlantic Beach, North Carolina
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt Marshzonation of plants in salt marshes
Zone location is related to height of tide
Varies accdg. To geographical location, substrate etc. Ex. Soil Salinity
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshCordgrasses – most common where it meets mudflats
Soil is drained , richer oxygen, less salty
May gradually invade mudflats
Stabilize soils by decreased wave action
California cordgrass (Spartina foliosa),
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshHome to decay bacteria, diatoms, green algae, & cyanobacteria.
Bacteria decompose – major source of detritus
Some bacteria are nitrogen fixers –enrich sediment
Animals: burrowing animals in mudflats
Nematodes, small crustaceans, larvae of land insects
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshAnimals:
Fiddler crabs – burrows along mudflat edge → increase oxygenation
Scavengers:
SesarmaHemigrapsus
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshAnimals:
Air breathing snails that feed on detritus, algae, fungi that grow on marsh plants
Coffee bean snails (Melampus) Marsh periwinkles (Littorina)
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Salt MarshAnimals:
Horse Mussel Juvenile Silverside American coot
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Mangrove ForestTropical equivalent to salt marshes
Mangroves → Mangals
75% of sheltered tropical shores are surrounded by mangroves
Need fresh water for growthBlack Mangrove leaf
Mangrove Forest
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Mangrove Forest
mangrove forest on the southern coast of Puerto Rico.
Mangrove ForestRed Mangrove
Lives right on the shore
Roots branch downward
along the shores of southern
Florida, the Caribbean, and the gulfs of California and Mexico
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Rhizophora mangle
Mangrove ForestBlack Mangrove
Along the Caribbean and Atlantic coasts of the Western Hemisphere
Seedlings can survive high salinity
Develop pneumatophores -aerate the plant
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Avicennia germinans
Mangrove ForestWhite Mangrove
Found only along the land ward edge of the forest
Sweat glands
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Laguncularia racemosa
Mangrove ForestAnimals:
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Sesarma Cardisoma mudskipper(Periophthalmus)
Indo-West Pacific mangrove forests and mudflats
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Mangrove ForestAnimals:
Sponges – provide nitrogen compounds. Protect the roots from isopods
polychaetes, mud shrimps, and clams at the muddy bottom
rich nurseries for many species of commercially important shrimps, spiny lobsters, and fishes
Rawr!
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Mangrove ForestAnimals:
Birds, snakes, frogs, lizards, bats & other land animals
Detritus are broken down by bacteria
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Other Estuarine CommunitiesMuddy bottoms below low tide
Seagrasses:
Roots help stabilize sediment
Leaves shelter many organisms
Source of detritusEelgrass(Zostera)-temperate
Turtle grass(Thalassia)-warm
Estuaries as Ecosystems• TYPES OF ESTUARINE COMMUNITIES
Other Estuarine CommunitiesOyster reefs:
Form beds in temperate waters
Provide 3-d surface for many
organisms
Oyster-reef community:
seaweeds, sponges,
tubeworms,
barnacles,
Estuaries as Ecosystems• FEEDING INTERACTIONS
Human Impact on Estuarine Communities
Salt marshes in Southern California and in many other locations around the globe havebeen obliterated with reclamation.
dredging of navigation channels destroys salt marshes
Human Impact on Estuarine Communities
Mangrove forests converted to Shrimp mariculture, and causes pollution
Clearing of Mangroves for urban development, roads, garbage dumps
Mangrove forests once fringed around 75% of all sheltered tropical coastlines, but 35 to 50% of these mangrove forests have been destroyed.