estuaries and coasts

Estuaries and Coasts

Notes Series for Oceanography MARS 2202

by

John P. Wnek

Coastlines and Productivity

Coastal diagram with the area of nearshore and offshore productivity

oceanworld.tamu.edu

Beaches

http://www.usa-chamber.com/gulf-beaches/home.html

High Productivity Coastal Areas

from NASA (SeaWIFS)

Coastal Types

Rocky Coasts Mountain Coasts Northern Boreal Coasts

Western Coasts U.S. Barrier Island Coast

Northeast Coast Habitats

/www.epa.gov/owow/estuaries/programs/se.htm

J Wnek

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”

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 Pamlico Sound)

• 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)

Sandy Hook, N.J.

Ocean City, Maryland

Aerial view of Oregon Inlet with highway 12- on Hatteras Island, NC. (Mallison et al. 2009)

Mallison, Riggs, Culver and Ames, East Carolina University, 2009

Geological sequence of sea level rise and the succession of Pamlico Sound

San Francisco Bay Estuary – a tectonic estuary

ONR.NAVY.MIL

Geiranger Fjord, Norway Kejser Franz Joseph Fjord, Greenland

Kenai River Delta, Alaska

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.

•Key: •Upwelling•Nor’easter

Cruz and Wnek, Summer 2012

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)

Inverse Estuaries

• Some estuaries show an increase in salinity over time, these are considered “inverse 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)

Swan River Estuary, W. Australia (Neira et al., 1992)

(Zedler et al. 2001)

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

Flushing Time* ComparisonsEstuary Minimum Maximum Mean

Chesapeake Bay, MD-VA

210 days (Guo)

Delaware Bay, DE-NJ

100 days(Delaware Estuary Program)

Barnegat Bay, NJ

24 days (January 1995)

74 days (June/July 1995)

49 days (Guo)

North River, MA

3 days (Geyer)

9 days

(Geyer)

Not determined

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).

Marsh Zones (Jones and Strange 2006)

Anthropogenic Effects on Coastlines

Coastal erosion in Norfolk in 1997

Human Impacts and Changes in Estuaries

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 Bay and human impacts

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.

Delaware River Fluxes in Sea Level Rise

Marsh Systems

Hartig et al. 2002

Hartig et al. 2002

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.

Proposed Bruun Model with changing sea level

Shifting of dunes and berms in response to sea level rise

Mallison, Riggs, Culver and Ames, East Carolina University, 2009

Concentrations (mg/l except for pH) of major ionic constituents in sea water [natural or formulated with synthetic sea salts (35 g/l TDS)], dilute sea water (5 g/l TDS) and vertebrate extracellular fluid (ECF) - - adapted from Wurts and Stickney, 1989, Aquaculture, 76: 21-35.Ions Sea water1

(35 g/l TDS)Dilute sea water(5 g/l TDS)

ECF2

(9 g/l TDS)Sodium 10685 1526 3265Potassium 396 57 195Calcium 410 59 100Magnesium 1287 184 36Chloride 19215 2745 3652Bicarbonate 142 20 1708Sulfate 2511 359 48pH 7.8-8.4 7.8-8.4 7.41Gross (1977).2Guyton (1971).

ReferencesAble, K, D.A. Witting, R. McBride, R. Rountree, and K.J. Smith. 1996. Fishes of polyhaline estuarine shores in

Great Bay-Little Egg Harbor, New Jersey: a case study of seasonal and habitat influences in Estuarine Shores by K.F. Nordstrom and C.T. Roman (eds.). John Wiley and Sons, England: pp. 335-353.

Candolin, U., T. Salesto, and M. Evers. Changed environmental conditions weaken sexual selection in sticklebacks. 2006. The Authors: Journal Compilation in the European Society for Evolutionary Biology 20: pp. 233- 239.

Carlson, D.M., and R.A. Daniels. 2004. Status of Fishes in New York: Increases, Declines, and Homogenization of Watersheds. American Midland Naturalist 152: pp. 104-139.

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.

Diffenbaugh, N.S., M.A. Snyder, and L.C. Sloan. 2004. Could CO2- induced land cover feedbacks alter near-shore upwelling regimes. Proceeding of the Natural Academy of Science, 101 (1): pp. 27-32.

Dybas, C.L. 2006. On a Collision Course: Ocean Plankton and Climate Change. BioScience 56 (8): pp. 642-646.

Galbraith, H., R. Jones, J. Clough, S. Herrod-Julius, B. Harrington, and G. Page. 2002. Global Climatic Change and Sea Level Rise: Potential Losses of Intertidal Habitat for Shorebirds. Waterbirds 25 (2): pp. 173-183.

Guo, Q., N. P. Psuty, G.P. Lordi, S. Glenn, and M.R. Mund.1995. Hydrographic Study of Barnegat Bay, Year 1: Volume 1 and 2. Prepared by the Rutgers the State University of New Jersey, New Brunswick, NJ, for the New Jersey Department of Environmental Protection, Division of Science and Research.

Guo, Q. and Valle-Levinson. 2007. Tidal effects on estuarine circulation and outflow plume in the Chesapeake Bay. Continental Shelf Research 27: 20-42.

References (cont’d)Gray, V.R., 1998. "The IPCC future projections: are they plausible". Climate Research 10 pp. 155-162

Green, R., J.E. Maldonado, S. Droege, and M.V. McDonald. 2006. Tidal Marshes: A Global Perspective on the Evolution and Conservation of their Terrestrial Vertebrates. BioScience 56 (8): pp. 675 – 685.

Hartig, E.K., V. Gornitz, A. Kolker, F. Mushacke and D. Fallon. 2002. Athropogenic effects and climate-change impacts on salt marshes of Jamaica Bay, New York City. Wetlands 22 (1): pp. 71 – 89.

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.

Jones, R. and E. Strange. 2006. A Pilot Study of the Ecological Consequences of Human Responses to Sea Level Rise. Stratus Consulting Inc., Boulder Colorado as part of a supporting document for the Barnegat Bay National Estuary Program’s Conservation and Management Plan (item 4.1): pp. 1- 61.

Neira, F.J., I.C. Potter, and J.S. Bradley. 1992. Seasonal and spatial changes in the larval fish fauna within a large, temperate Autralian estuary. Marine Biology 112: 1- 16.

Ogdon, J., S.M. Davis, T.K. Barnes, K.J. Jacobs, and J.H. Gentile. 2005. Total System Conceptual Ecological Model. Wetlands 25 (4): 955-979.

Reed, D.J., D.A. Bishara, D.R. Cahoon, J. Donnelly, M. Kearney, A.S. Kolker, L.L. Leonard, R.A. Orson, and J.C. Stevenson. 2006. Site-specific scenarios for wetlands accretion as sea level rises in Mid-Atlantic Region. Supporting document for CCSP 4.1 to Climatic Change Division U.S. Environmental Protection Agency: pp. 1- 54.

Zedler, J.B. 2005. Restoring wetland plant diversity: a comparison of existing and adaptive approaches. Wetlands Ecology and Management 13: 5-14.