Hoskins lecture: Coastal Citizens - a Brief Primer of the Goergia Coast

Coastal Citizenship: A Coastal Citizenship: A Brief Primer on the Brief Primer on the

Georgia CoastGeorgia Coast

Dionne HoskinsNOAA Sponsored Programs

NOAA Living Marine Resources Cooperative Science Center

Savannah State University

Distinguished Lecture Series

Fall 2014

Georgia Coast12 subtropical barrier islands

2-7ft tidal range (mesotidal)

Many undeveloped

Wassaw, Blackbeard, Ossabaw, Little Tybee

Less developed

Little Saint Simons,

Sapelo, Cumberland,

Little Cumberland (private)

Developed

Tybee, Jekyll, St. Simons,

Sea Island

1. Maritime Forests1. Maritime Forests

Among the most extensive on Atlantic coastMaintain barrier island stabilityStore precipitation in the surface water tableHabitat for rare speciesStabilize mineral cycling through growth and decomposition

Beaches are windy, dynamic environments with irregular water currents and are fairly difficult habitat for most plants and shore life.

2. Beaches2. Beaches

More

life here

More life

back here Not so

much here

We are enamored with this premium part of our environment and try to manage it.

From Bertness 1999

Sea level rise?

Post Hurricane Ike, from USCG Galveston

N→S currents erode northern ends and move soft sediment to landward southern ends.

Accretion occurs on southern ends and promotes marsh development.

From Bertness 1999

3. Natural Forces Change Coastal 3. Natural Forces Change Coastal LandscapesLandscapes

The shapes of barrier islands are constantly changing.

4. Marshes4. Marshes

Marshes have 3D structure that provides spawning, nursery, refuge, and foraging grounds for fisheries species and storm protection for shorelines.

Coastal landscape structure affects natural processes and ecosystem services.

5. Fresh and tidal coastal water 5. Fresh and tidal coastal water flows (hydrologic characteristics) flows (hydrologic characteristics) define tidal marshesdefine tidal marshes

Hydrologic characteristics define tidal marshes –freshwater flows from coastal watersheds and saline ocean tides

Courtesy of R. Kneib 2003

There is repetition in natural patterns of how water shapes coastal areas.

Courtesy of R. Kneib 2003

Tidal creek subsystemTidal creek subsystem

You see it at multiple scales

-system

-river

-tidal creek

Water brings nutrients into the system that increase primary productivity.

Structure of creek sub-sub-systemStructure of creek sub-sub-system

Across all habitats (i.e., forests, wetlands), ecosystem services are fundamental life-support processes upon which all organisms depend (Daily et al., 1997).

Among other things, theyproduce ecosystem goods (ex. food, timber)generate and maintain biodiversitystabilize climate and life (ex. storms)mitigate floods and droughts andprovide aesthetic beauty and intellectual and spiritual

stimulation.

6. Natural habitats provide 6. Natural habitats provide ecosystem servicesecosystem services

Landscape complexity and fisheries– Landscape complexity and fisheries– The Threshold ConceptThe Threshold Concept

Kneib 2003

Marsh nekton sampling using a flume weir.

When assessing secondary production (animal biomass), we find that marsh habitat has a threshold (Kneib 1991) after which energy moves to the water.

the edge

The amount of intertidal marsh within a 200m radius of the sample site.

In marsh

This concept is called a “trophic relay.” Transfers to open estuarine waters may occur when material is either excreted in subtidally at low tide or when accumulated biomass is passed along via predator-prey interactions.This moves marsh production across the landscape. Destroy marsh- decrease productivity.

(Kneib 2002)

http://www.pseg.com

In a mitigation project, PSEG embarked on an unprecedented effort to help restore a portion of the Delaware Estuary by establishing the Estuary Enhancement Program (EEP) in 1994.

This is an example of applying what we know about the structure and function of marshes to restore ecosystem services.

Public Service Electric and Gas Company (PSE&G, New Jersey) Estuarine Enhancement Program

Problem: Diked marsh system with invasive plants and low productivity

Goal: To restore ecosystem functionality of a portion of the Delaware Estuary

•Returned diked salt hay farms (10,000 acres) to communication with Delaware Bay (water → nutrients)•Recover Phragmites-dominated sites to native species•Constructed fish ladders for river herring•Began biological monitoring•Construction of public use facilities and enhancements•Support for artificial reef programs in New Jersey and Delaware

The Trophic Relay concept applied

Restoring primary production restored habitat for fauna and increased fisheries.

1997

2008

They restored communication in the creek system.

(Kneib 2002)

7. Several Factors Affect Coastal 7. Several Factors Affect Coastal EnvironmentsEnvironments

Management

Applying science for coastal conservation

ScienceCoastal landscape

ecology and natural forces

Policy/PoliticsConsequences of the

socio-political environment

Culture

Uniqueness of island and coastal environments

Georgia’s coastal zone is shaped by two major forces◦The power of water currents – which

environmental science can help to understand

◦The power of currency – over which science has little or no influence

Thank you.Thank you.

SourcesSources

http://www.n-georgia.com/images/costIslndWeb.jpg

http://www.lternet.edu/sites/default/files/photo2%5B1%5D_1.jpg

http://georgiaseagrant.uga.edu/images/uploads/article_images/m-7713.jpg