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

Most plants can’t live in saltwater b/c osmosis dehydrates them 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 Fiddler crabs Worms Juncus 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 small fish Snails

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 Black White

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.

-Seeds look like large lima beans 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 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 red white black