Estuaries

A semi-enclosed costal body of water which has a free connection with the open sea and within which sea water is measurably diluted by fresh water derived from land drainage

Estuary

Estuaries can be classified on what two types of systems?

Geomorphology
Tidal range

The four geomorphology types of estuaries

Coastal plain
Tectonic
Fjord
Bar-built

What geomorphological classification of estuary is this?
River valley that drowned during the melting of the last ice age.
Deltas form at the mouths of these estuaries from river deposition

Coastal plain

What geomorphological classification of estuary is this?
Formed by faulting and volcanic eruptions. Estuary formed between two fault lines

Tectonic

What geomorphological classification of estuary is this?
Formed by glaciers that moved seaward and dug out deep trenches before retreated.
Marked by very steep walls around the estuary

FjordWhat geomorphological classification of estuary is this?

What geomorphological classification of estuary is this?
Lagoon formed between mainland and barrier islands. Very broad and shallow estuary

Bar-built

What are the four types of estuary based on tidal range?

Microtidal
Mesotidal
Macrotidal
Hypertidal

What type of estuary based on tidal range?
<2m tidal range
Gulf of mexico, coast of florida

Microtidal

What type of estuary based on tidal range?
2-4m tidal range
Much of the coast of GA and up into NE

Mesotidal

What type of estuary based on tidal range?
4-6m tidal range

Macrotidal

What type of estuary based on tidal range?
>6m tidal range
Bay of Fundy only one in the world

Hypertidal

What two factors from a hurricane affect the tidal magnitude of an estuary, causing extreme flooding?

High tide + wind field of the storm

Three regions of an estuary based on salinity (low to high)

Tidal river zone
Mixing zone
Nearshore turbid zone

What three types of forces affect the circulation of an estuary?

Solar
Gravitational
Passive forces

Even amounts of river input and tidal input will create an estuary that is

well-mixed

Estuaries with very high river input and low tide input will be extremely stratified, forming what’s known as a

salt wedge

High rates of respiration are net

heterotrophy

Estuaries with lots of nutrients coming from the land will have an upper layer that’s ____ in oxygen and a lower layer that’s very ____ in oxygen

high
low

In order to export out to sea, an organism should travel (up/down) during Ebb tide

up

In order to come into land from the sea, an organism should go (up/down) during flood tide

down

In order to retain position, an organism should go (up/down) during ebb tide

down

In order to retain position, an organism should go (up/down) during flood tide

up

Organisms time their spatial movement for nutrient maximization for what two reasons?

Minimize competition for a resource
Exploit a resource based on time of day/year

the ______ part of an estuary make a good area for a recent hatchling or an older adult life stage

Lagoon

The seagrass/mangrove area of an estuary has lots of cover, making it a good place for _____ and organisms to get ______

nursery
food

Blue crabs are what life stage in the river?

Adult

A blue crab with eggs will migrate to _____ to lay them

ocean

The larvae of a blue crab will grow to adult size in the

estuary