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CHAPTER IV: WILDLIFE HABITATS FOR MISSISSIPPI’S SGCN,
THREATS AND CONSERVATION ACTIONS^234

ecosystems. A healthy coastal economy depends on healthy coastal ecosystems. Refer to Section 14,
Estuary and Mississippi Sound, for additional discussion on conditions of coastal habitats.


13.1 Barrier Island Uplands


„ Value to SGCN - 87
„ Rank - 4th of 17 of Marine, Estuarine and
Estuarine Fringe Systems

DESCRIPTION
The dry island subtype includes dry to mesic
meadows and inland dune systems. Habitats consist
of excessively well-drained, mostly deep soils
composed of windblown sand. Some upland areas
are periodically overwashed by storm surges. The most erosive sections of the islands are directly
adjacent to the beaches where there is the least amount of vegetation cover and greatest exposure to
wind. As flats and berms along the backbeach become desiccated, the sand particles are less cohesive
and readily drift on windy days. Wind erosion, salt spray and exposure to excessive heat keeps the areas
sparsely vegetated. Slightly inland from the shore, a series of vegetated linear swales and dune ridges
parallel the coastline. The dunes are either semi-stable and display some active sand movement or stable
and firm.


The stable dunes, also called relict dunes, have a crust that is strengthened by the presence of
microscopic organisms. Excessive pedestrian traffic on hiking trails will disturb relict dunes, causing
them to erode, but they can also be buried by encroaching dunes. Backbeaches and semi-stable dunes
commonly support a sparse cover of a variety of graminoids, including gulf bluestem, Leconte's
flatsedge, sea oats, panic grass, dropseed and umbrella sedge. Common herbs are squareflower, poorjoe,
pineland scalypink, Dixie sandmat, camphorweed, coastal sands frostweed and beach morning glory.
The dry meadows are dominated by southern umbrellasedge, torpedo grass, broomsedge bluestem,
needlepod rush, panic grass and contain lesser amounts of saltmeadow cordgrass. Relict dunes are
dominated by shrubby species: wild rosemary, woody goldenrod, prickly pear, saw palmetto and
occasionally sand live oak.


LOCATION, SIZE, CONDITION AND CONSERVATION STATUS
NGM


Barrier island uplands consist of long narrow segments of land that are surrounded by brackish or
marine water. The uplands are exposed to frequent strong winds and tidal storm surges. The upland
substrates are sandy and dry. Each of the five islands support a total of 6,000 acres in long contiguous

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