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Estuaries, Coasts and our Oceans of Course. Notes Series for Research Methods. Review. Arctic. Atlantic. Pacific. Indian. Southern. Actually there is only 1 ocean as oceans exchange water and are interconnected. Science News, 2011. Great Pacific Garbage Patch.
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Estuaries, Coasts and our Oceans of Course Notes Series for Research Methods
Review Arctic Atlantic Pacific Indian Southern Actually there is only 1 ocean as oceans exchange water and are interconnected
Dr. Carl Safina who works on the effects of the patch displaying an item retrieved From National Geographic It is measured to be the 2 x the size of Texas
Eleven Major Constituents in seawater • These make up 99.99% of the salts in the ocean… • Bicarbonate, Boron, Bromide, • Calcium, Chloride, • Fluoride, Magnesium, • Potassium, • Sodium, Strontium, Sulfate. Two most abundant are underlined
High Productivity Coastal Areas from NASA (SeaWIFS)
Coastal Types Rocky Coasts Mountain Coasts Northern Boreal Coasts Western Coasts U.S. Barrier Island Coast
Coastlines and Productivity oceanworld.tamu.edu Coastal diagram with the area of nearshore and offshore productivity
Beaches http://www.usa-chamber.com/gulf-beaches/home.html
Basic Definition of Estuary – A water body where salt & freshwater mix Technical Definition - “A standing water body within the coastal region where there is a greater net inflow of freshwater than an influx of sea water” J Wnek
Estuary Types: Classified by Geology • Lagoon – parallel to coast (i.e. Indian River Lagoon, Florida) – Bar-Built Estuaries • Coast Plain Estuary– erosion (i.e. Chesapeake Bay and Delaware Bay)
Estuary Types: by Geology • Tectonic Estuary– faults (i.e. San Francisco Bay) • Fjord – glacier formation (i.e. Alaska, British Columbia, Norway, Chile) • Delta- formed at mouth of a river (i.e. – Mississippi Delta)
Aerial view of Oregon Inlet with highway 12- on Hatteras Island, NC. (Mallison et al. 2009)
Geological sequence of sea level rise and the succession of Pamlico Sound Mallison, Riggs, Culver and Ames, East Carolina University, 2009
ONR.NAVY.MIL San Francisco Bay Estuary – a tectonic estuary
Kejser Franz Joseph Fjord, Greenland Geiranger Fjord, Norway
Factors influencing an estuary • Temperature • Salinity • Nutrients Anthropogenic effects (review) • Increased runoff • Development causing habitat fragmentation • Global Climatic Changes
Temperature • Temperatures may change with shifting tidal regimes • There can be temperature inversions during the evenings, especially in the fall when cooler temperatures may be at the surface.
Classification of Systems • Nontidal Fresh 0 ppt, no tidal influence • Tidal Fresh 0 - 1 ppt, tidal influence • Oligohaline 2 - 5 ppt (slightly brackish) • Mesohaline 8 - 15 ppt (brackish) • Polyhaline 18 ppt and up (salt water)
Salinity • Salinity can vary in estuaries based upon the amount of salt water inflow and freshwater inputs. • Estuaries can be classified according to the layering of salt water based on density - well-mixed - partially-mixed - salt wedge (highly stratified)
Reverse Estuaries • Some estuaries show an increase in salinity over time, these are considered “reverse estuaries” or “negative estuaries.” • There is a net increase in salinity over time mostly due to human impacts (i.e. dams and loss of freshwater flow into the system)
(Zedler et al. 2001) Swan River Estuary, W. Australia (Neira et al., 1992)
Flushing Time? • Considered the amount of time in which all water is totally exchanged in an estuary • Varies according to the estuary due to ocean access, freshwater runoff (called inflow) and depth of the estuary tF = VF / R tF is the flushing time Vf is the freshwater volume R is the river discharge rate This equation is not required
Marsh Zonation • High Marsh – Not flooded regularly with predominant Spartina patens and Phragmites • Series of marsh pools at higher elevations • Low Marsh – Floods regularly with Spartina alterniflora • Creeks and ditches with sometimes tidal effects • Support a higher density of finfish than SAV beds (Sogard and Able 1991).
Anthropogenic Effects on Coastlines Coastal erosion in Norfolk in 1997
Human Impacts and Changes in Estuaries Delaware Bay and human impacts In the past eighteen thousand years, sea level has risen one hundred meters (three hundred feet), converting freshwater rivers into brackish estuaries (Donn, Farrand, and Ewing 1962). The Delaware River is an Alluvial Plain
Delaware River Fluxes in Sea Level Rise Hull, C.H.J. and J.G.Titus (eds). 1997. Greenhouse Effect, Sea Level Rise, and Salinity in the Delaware Estuary.. Washington, D.C.: U.S. Environmental Protection Agency and Delaware River Basin Commission.
Proposed Bruun Model with changing sea level Shifting of dunes and berms in response to sea level rise Davidson-Arnott, R. 2005. Conceptual model of the effects of sea level rise on sandy coasts. Journal of Coastal Research 21 (6): pp. 1166-1172.
Mallison, Riggs, Culver and Ames, East Carolina University, 2009