Coastal Plain Region Of Georgia

Georgia's Lower Littoral Plain, an environmental region of the Coastal Evidently Province, contains some of the state'southward most well-known geographic features—the littoral barrier islands and the Okefenokee Swamp. The state's everyman elevations and its highest percentage of wetlands—including tidal table salt and brackish marshes, bottomland hardwood swamps, and the Okefenokee—are found in the Lower Littoral Plain.

Geologists, biologists, and other scientists disagree on the extent of the area occupied by the region. In full general, wildlife biologists and other experts refer to the Lower Littoral Plain every bit the area roughly covering a twenty-seven-county "ecoregion" designated as the Southern Littoral Plain. That region extends inland about sixty-five to seventy miles from the seashore. Its boundary stretches beyond the lower portion of the land from Screven County in southeast Georgia to Echols Canton to the southwest.

The topography of the Lower Coastal Plain is generally low, flat, and swampy where information technology borders the Atlantic, and grades to depression rolling hills at the inner margin. It is at a lower distance and has less relief than the Upper Coastal Plain. Agronomical and most other commercial activities in the Lower Coastal Plain are concentrated on its college and drier ground. In inland areas of the Lower Coastal Patently, water depth fluctuates with rainfall and the seasons. The sandy soil tends to blot streamflow, especially during drought, when the water table falls. The sand besides actsas temporary storage space to blot some of the overflowing flows.

Land cover in the region is mostly slash and loblolly pine, with oak-gum-cypress forest in some depression-lying areas, and pasture for beef cattle.

Physiographic Districts

The Lower Coastal Plainly contains several subregions, or physiographic districts, based on topography, geology, soil, flora, fauna, and other factors. The nearly notable of these districts are the Barrier Island Sequence and the Okefenokee Bowl.

The Barrier Island Sequence includes primordial seashores and the nowadays-day coastline. The expanse is composed primarily of a series of vi prehistoric terraces. The parallel terraces were formed during the geologically recent Pleistocene epoch, also known as the Ice Ages, which began nearly 2 one thousand thousand years agone. The terraces represent primordial shorelines created past fluctuating sea levels. The old shorelines were like to Georgia's nowadays-day seashore, marked by sweeping salt marshes, tidal creeks, and short, wide barrier islands separated by deep sounds.

At the beginning of the Pleistocene, virtually of southeast Georgia, a portion of southwest Georgia, and probably the unabridged Florida peninsula were beneath the sea and part of the continental shelf. The Pleistocene was a fourth dimension of irresolute sea levels equally the nifty continental glaciers of northern North America and Eurasia advanced and retreated, causing sea levels to rise and autumn.

The old shorelines, or terraces, formed where the fluctuating sea levels temporarily stopped or stabilized. Today, in cross department, the Barrier Island Sequence district resembles a serial of steps, or terraces, descending to the sea. The terraces are visible as sand ridges and account for some relief in the otherwise apartment and depression-lying Lower Coastal Plain.

The furthermost of the Pleistocene shorelines is known as the Wicomico, which lies up to sixty miles west of the present Atlantic Ocean shore and adult when the sea level was approximately 100 anxiety higher than the present level. Later on the Wicomico barrier, several sequences of barrier islands occurred: Penholoway, which adult when sea level was nigh 75 anxiety above present level; Talbot, 40-45 feet; Pamlico, 25 feet; Princess Anne, 15 anxiety; and Silverish Bluff, 5 anxiety.

In some cases the sand ridges influence the present-day courses of several Georgia rivers. The Ogeechee and Altamaha rivers suspension through these ridges and flow directly to the ocean, but the Satilla River makes a twenty-mile dogleg in Wayne County, where it is trapped betwixt the Penholoway and Talbot embankment complexes, before information technology breaks through the latter to the body of water. The St. Marys River makes an fifty-fifty larger doglegin the opposite management. Every bit a result, there is a large poorly drained area in Charlton and Ware counties.

The Wicomico shoreline featured an unusually large barrier island, now called Trail Ridge. It obstructed the drainage of a cracking salt marsh more 700 foursquare miles in size. That basin became the present-24-hour interval Okefenokee Swamp.

Today's Bulwark Islands

Georgia meets the Atlantic Ocean along the sandy beaches of the present-24-hour interval bulwark islands, known as the Body of water Islands or the Golden Isles. Scientists refer to them as barrier islands because they grade a barrier between the sea and the country. The current configuration of Georgia's shoreline is only the almost recent in a long series of changing shorelines.

Lower Coastal Plain Map — Lower Littoral Plain Map

The islands are equanimous basically of dune and beach-ridge sands. They were shaped—and are still being altered—by air current, waves, currents, tides, and a slowly rising or stable sea level. From northward to due south along Georgia'south 100-mile-long declension, the barrier islands are Tybee, Little Tybee, Wassaw, Ossabaw, St. Catherines, Blackbeard, Sapelo, Wolf, Little St. Simons, St. Simons, Sea, Jekyll, Little Cumberland, and Cumberland. (Skidaway Island, about Savannah, is said to be an inshore barrier island. It lacks the wide, sandy beach typical of Georgia's outer barrier islands.)

Separated from the mainland by a four- to six-mile-wide ring of table salt marsh, tidal creeks, and estuaries, Georgia's barrier islands are under various types of buying and direction.

Jekyll, Sea Island, St. Simons, and Tybee islands are developed and connected to the mainland by bridges and causeways. Much of Jekyll is a state park.

The other bulwark islands are accessible only by boat. Of these, Blackbeard, Wassaw, and Wolf islands are national wildlife refuges. Little Tybee, Ossabaw, and Sapelo are owned past the land of Georgia. The Cumberland Island National Seashore is managed by the National Park Service. Lilliputian Cumberland, Trivial St. Simons, and St. Catherines are privately owned.

Georgia's barrier islands, as well as those of southern South Carolina and northern Florida, are of two generations. The older islands are called Pleistocene in reference to the geologic period in which they were formed. Examples of Pleistocene islands include Sapelo and St. Simons, formed 35,000 to forty,000 years ago. The "younger" barrier islands are referred to as Holocene. Examples include Lilliputian St. Simons, Bounding main, and Wassaw islands, which formed 4,000 to 5,000 years agone. The Pleistocene islands tend to be flatter with well-developed soils, whereas the Holocene islands accept many dune ridges and poor soils.

The barrier islands today typically have 4 ecosystems: sweeping salt marshes, maritime forests, freshwater sloughs, and hard-packed sandy beaches. On the islands' western sides are the vast tidal table salt marshes, composed mostly of the salt-tolerant plant Spartina alterniflora, or shine cordgrass. The coastal marshes, tidal creeks, and connecting estuaries are of import nursery areas for fish, crab, shrimp, and other marine species.

At the edge of the marsh, the maritime forest begins. The transition from marsh to forest is sharp. The forests of Georgia'due south islands frequently are more all-encompassing and better developed than those of other U.S. barrier islands. Canopies of Georgia's mature maritime forest are dominated by alive oaks festooned with Spanish moss. Other big canopy trees include southern magnolias, pines, and cabbage palms. Pine stands are ordinarily found in the younger, southern ends and ocean sides of the isle forests. The trees often are intertwined with woody vines. Forming the forest understory are shrubs and such smaller trees as American holly, cherry laurel, redbay, saw palmetto, sparkleberry, wax myrtle, and yaupon holly.

Freshwater sloughs in the woods interior usually are seasonal or year-round ponds filled with rainwater. The wetlands provide important habitat for alligators, water birds, otters, and other island wild fauna. On islands with significant human being development, such ponds, if non drained and filled, often are used every bit water hazards on golf courses.

Barrier-isle beaches are characterized by wide, intertidal, gently sloping expanses of hard-packed, fine white quartz sand. The beaches often extend from the normal high-tide line to about thirty anxiety below the low-tide line. Facing a embankment on its landward side is a wall of young "primary sand dunes," sculpted past wind and waves. Their faces are raw and steep. These primary dunes are the island's commencement line of defense against the sea. Morning glories, pennyworts, sea oats, and other plants abound on the dunes and assist to stabilize them.

Farther back stand up older, larger, steeper dunes of fine, soft sand. On some barrier islands, such as on Cumberland, they rise more 50 feet and provide backup protection to the principal dunes against wind and storms. Betwixt the principal and rear dunes are meadows of grasses, sedges, and such shrubs every bit wax myrtle, which attract seed-eating birds, rabbits, and other modest mammals.

The islands and the side by side coastal mainland have a long history of human alterations. Native Americans hunted and fished there and cultivated beans, corn, melons, and squash; a Spanish mission period during the 1500s-1600s included crops of artichokes, citrus, figs, olives, onions, and peaches; and a plantation agriculture economy in the late eighteenth through the nineteenth centuries produced indigo, rice, Sea Isle cotton wool, and sugar pikestaff.

In the late 1800s and early 1900s, wealthy northerners purchased several of Georgia's bulwark islands and turned them into private resorts and retreats. The private owners, for the almost part, kept their islands undeveloped.

Coastal Industry

Coastal fisheries and forest resource support a number of industries engaged in processing, manufacturing, and marketing seafoods and wood products. In general, tourism and recreation, shipping at the ports of Savannah and Augusta, papermaking, commercial fishing, and forestry have been the most important economic activities of Georgia'southward modern coast. Over the decades the pulp and paper manufacture expanded at the expense of the fishing industry, which has suffered greatly from pollution caused past the paper mills.

Electric current Threats to the Coast

Growth projections for Georgia'due south declension point a 20 percent population increase per decade over the adjacent few decades. Thank you to the protected status of most of Georgia's bulwark islands, the majority of them should be spared many problems typically associated with rapid and extensive unplanned development.

Still, as bounding main levels rise due to global warming, the erosion of barrier isle beaches is expected to increase. Already, expensive renourishment projects are needed to maintain recreational beaches on Sea Isle and Tybee Island. Approximately 55 percent of the nineteen miles of embankment shoreline on Jekyll, Sea, St. Simons, and Tybee islands have been reinforced with either physical sea walls or revetments of granite boulders in an effort to command natural erosion. The structures destroy the artful quality of beaches and leave little or no beach expanse available at hightide for recreation.