Middle Atlantic coastal forests

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Middle Atlantic coastal forests
Baldcypress (Taxodium distichum) on Congaree National Park Low Boardwalk trail.jpg
Middle Atlantic coastal forests map.svg
Ecology
Biome Temperate coniferous forests
Borders Southeastern conifer forests, Southeastern mixed forests and Northeastern coastal forests
Bird species 237[1]
Mammal species 58[1]
Geography
Area 133,600 km2 (51,600 sq mi)
Country United States
States Delaware, Maryland, Virginia, North Carolina, South Carolina and Georgia
Conservation
Habitat loss 39.3%[1]
Protected 11.3%[1]

The Middle Atlantic coastal forests are a temperate coniferous forests ecoregion of the United States.

Setting[edit]

The Middle Atlantic coastal forests stretch along the Atlantic coast of the United States from the Delmarva Peninsula south to the Georgia coast. They cover the Atlantic coastal plain and are bordered on the west by the Southeastern mixed forests.[2]

The habitats of the ecoregion are constantly modified by natural processes. The bottomlands, coastal plains, and maritime areas are vulnerable to hurricanes and floods. The drier areas are susceptible to fires. Fire return intervals of 1 to 3 years favor herbaceous plants; longer intervals favor dense shrubs.[2]

Climate[edit]

This ecoregion has a humid subtropical climate with hot summers and significant precipitation in all seasons.

Flora[edit]

Southern mixed pine-oak forests are the characteristic forest community of this ecoregion. These forests occur on dry or sandy soils or in areas exposed to occasional fires. Longleaf pine (Pinus palustris), superbly adapted to fire-prone environments, is the principal tree of these forests. Loblolly pine (Pinus taeda) and shortleaf pine (Pinus echinata) grow in sandy soils. On moist soils or where fires are infrequent, hardwoods overtake the pines. These hardwoods include turkey oak (Quercus laevis), post oak (Quercus stellata), myrtle oak (Quercus myrtifolia), Spanish oak (Quercus falcata), and southern catalpa (Catalpa bignonioides). On sandy soils, particularly near the coast and on coastal islands, live oak (Quercus virginiana) thrives, often draped with Spanish moss (Tillandsia usneoides). Common shrubs of these forests are saw palmetto (Serenoa repens), southern bayberry (Myrica cerifera), and Carolina holly (Ilex ambigua).[3]

Southern hardwood forests grow on moist sites. Spanish moss is abundant and is an indicator species of this habitat. Southern magnolia (Magnolia grandiflora), an evergreen tree with tropical origins, grows here. Sweetbay (Magnolia virginiana) and cucumbertree (Magnolia acuminata) grow here as well. Other trees that grow here are common persimmon (Diospyros virginiana), and Virginia live oak.[3]

The Middle Atlantic coastal forests contain the most diverse assemblage of freshwater wetland communities in North America. These include freshwater marshes, shrub bogs, white cedar swamps, bayheads, and wet hammocks.[2]

The bottomland hardwood forests for which the ecoregion is famous are dominated by baldcypress (Taxodium distichum) and swamp tupelo (Nyssa sylvatica var. biflora).[2]

Baldcypress swamps are often dominated by their namesake tree, and are too wet for foot travel. Many uncommon orchids grow among the baldcypress branches.[3]

Swamp tupelo, along with water tupelo (Nyssa aquatica), dominate mixed-hardwood swamp forests. These grow aside water-adapted oaks that include water oak (Quercus nigra), swamp chestnut oak (Quercus michauxii), cherrybark oak (Quercus pagoda), willow oak (Quercus phellos), and overcup oak (Quercus lyrata). Swamp hickory (Carya glabra) and water hickory (Carya aquatica) are also found here. Pawpaw (Asimina triloba) grows in the understory.[3]

Atlantic white cedar (Chamaecyparis thyoides) swamps occur along blackwater rivers.[2]

Pocosins are flat and damp, sandy, or peaty areas far from streams. They have scattered pond pine (Pinus serotina) and a dense growth of mostly evergreen shrubs including gallberry (Ilex glabra).[2]

Barrier islands along the coast protect extensive estuaries, lagoons, and sounds.[2]

Carolina bays are a unique habitat of the ecoregion.[2]

Fauna[edit]

The nine-banded armadillo (Dasypus novemcinctus) is a distinctive animal that lives in this ecoregion. The Virginia opossum (Didelphis virginiana) is abundant.[3]

In the mixed pine-oak forests, the brown-headed nuthatch (Sitta pusilla) feeds on pine seeds. The yellow-throated warbler (Dendroica dominica) is widely distributed. The northern parula warbler (Parula americana) and the eastern bluebird (Sialia sialis) are also found here. The Bachman sparrow (Aimophila aestivalis) and red-cockaded woodpecker (Picoides borealis), both uncommon, also live in this ecoregion.[3]

The bottomland forests support abundant arthropods, produce mast that sustains migratory birds during the winter, and produce boles, branch cavities, and rotting logs that support various detritivores and hole-nesting species.[2]

Contemporary land use[edit]

The main causes of habitat conversion are agriculture, fire suppression, urbanization, coastal development, ditching and draining of wetlands, and damming of rivers.[2]

The western part of the ecoregion has been most altered. There, the upland vegetation has been nearly completely converted.[2]

Long-leaf pine (Pinus palustris) savannas have nearly disappeared.[2]

The least altered habitats in the ecoregion are the coastal marshes and deep peatlands.[2]

Remaining intact habitat[edit]

References[edit]

  1. ^ a b c d Hoekstra, J. M.; Molnar, J. L.; Jennings, M.; Revenga, C.; Spalding, M. D.; Boucher, T. M.; Robertson, J. C.; Heibel, T. J.; Ellison, K. (2010). Molnar, J. L., ed. The Atlas of Global Conservation: Changes, Challenges, and Opportunities to Make a Difference. University of California Press. ISBN 978-0-520-26256-0. 
  2. ^ a b c d e f g h i j k l m "Middle Atlantic coastal forests". Terrestrial Ecoregions. World Wildlife Fund. 
  3. ^ a b c d e f Kricher, John; Morrison, Gordon (1998). Eastern Forests: A field guide to birds, mammals, trees, flowers, and more. Houghton Mifflin Harcourt. ISBN 978-0-395-92895-0.