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Carolina bays are elliptical depressions concentrated along the Atlantic seaboard within coastal Delaware, Maryland, New Jersey, North Carolina, South Carolina, Virginia, Georgia, and northcentral Florida (Prouty 1952, Kaczorowski 1977). In Maryland, they are called Maryland Basins (Rasmussen and Slaughter 1955). Within the Delmarva Peninsula, they and other coastal ponds are also called Delmarva bays (Coleman nd). Other landform depressions, not widely accepted as Carolina bays, are found within the northern Gulf of Mexico coastal plain in southeast Mississippi and Alabama, where they are known as either Grady ponds or Citronelle ponds (Otvos 1976, Folkerts 1997). Carolina bays vary in size from one to several thousand acres. About 500,000 of them are present in the classic area of the Atlantic Coastal Plain, often in groups, with each bay invariably aligned in a northwest-southeast direction. The bays have many different vegetative structures, based on the depression depth, size, hydrology, and subsurface. Many are marshy; a few of the larger ones are (or were before drainage) lakes; 36 square km (14 square mile) Lake Waccamaw is an undrained one. Some bays are predominantly open water with large scattered pond cypress, while others are composed of thick, shrubby areas (pocosins), with vegetation growing on floating peat mats. Generally the southeastern end has a higher rim composed of white sand. They are named for the bay trees frequently found in them, not because of the frequent ponding of water (Sharitz 2003). Undrained, often circular to oval, depressions exhibiting a wide range of area and depth are also a very common feature of the Gulf of Mexico coastal plain within Texas and southwest Louisiana. These depressions vary in size from 0.4 to 3.6 km (0.25 to 2 miles) in diameter. Within Harris County, Texas, raised rims, which are about 0.65 m (2 ft) high, partially enclosed these depressions. In the scientific literature, they are known by a variety of names, including ''pocks'', ''pock marks'', ''bagols'', ''lacs ronds'', and ''natural ponds'' (Aronow nda, Aronow ndb). ==Ecological significance and biodiversity== The bays are especially rich in biodiversity, including some rare and/or endangered species. Species that thrive in the bays' habitats include birds, such as wood storks, herons, egrets, and other migratory waterfowl, mammals such as deer, black bears, raccoons, skunks, and opossums. Other residents include dragonflies, green anoles and green tree frogs. The bays contain trees such as black gum, bald cypress, pond cypress, sweet bay, loblolly bay, red bay, sweet gum, maple, magnolia, pond pine, and shrubs such as fetterbush, clethra, sumac, button bush, zenobia, and gallberry. Plants common in Carolina bays are water lilies, sedges and various grasses. Several carnivorous plants inhabit Carolina bays, including bladderwort, butterwort, pitcher plant, and sundew. Some of the bays have been greatly modified within human history, under pressure from farming, highway building, housing developments and golf courses. Carvers Bay, a large one in Georgetown County was used as a bombing practice range during World War II. It has been drained and is mostly used for tree farming today. Others are used for vegetable or field crops with drainage. In South Carolina, Woods Bay, on the Sumter-Clarendon County line near Turbeville has been designated a state park to preserve it as much as possible in its natural state. Also in Clarendon County (near Manning), another bay, Bennett's Bay, is a Heritage Preserve. Another bay in Bamberg County, South Carolina is owned by the South Carolina Native Plant Society, which has been developing a preserve called the Lisa Matthews Memorial Bay, which is trying to preserve and increase the federally endangered wildflower ''Oxypolis canbyi'' (Canby's Dropwort) in the bay. The uplands area surrounding the bay is being restored from a loblolly pine plantation to the original longleaf pine. Included in the longleaf restoration is the restoration of wiregrass (''Aristida beyrichiana'') as a key understory plant. Its flammability aids in periodic burning, which is necessary for Canby's Dropwort and many of the other species unique to the environment. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Carolina bay」の詳細全文を読む スポンサード リンク
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