Английская Википедия:Appalachian Mountains

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The Appalachian Mountains,Шаблон:Efn often called the Appalachians, are a mountain range in eastern to northeastern North America. Here, the term "Appalachian" refers to several different regions associated with the mountain range, and its surrounding terrain. The general definition used is one followed by the United States Geological Survey and the Geological Survey of Canada to describe the respective countries' physiographic regions. The US uses the term Appalachian Highlands and Canada uses the term Appalachian Uplands. (The Appalachian Mountains are not synonymous with the Appalachian Plateau which is one of the provinces of the Appalachian Highlands).

The Appalachian range runs from the Island of Newfoundland in Canada, Шаблон:Convert southwestward to Central Alabama in the United States;Шаблон:Efn south of Newfoundland, it crosses the 96-square mile archipelago of Saint Pierre and Miquelon, an overseas collectivity of France, meaning it is technically in three countries.Шаблон:Efn The highest peak of the mountain range is Mount Mitchell in North Carolina at Шаблон:Convert, which is also the highest point in the United States east of the Mississippi River.

The range is older than the other major mountain range in North America, the Rocky Mountains of the west. Some of the outcrops in the Appalachians contain rocks formed during the Precambrian era. The geologic processes that led to the formation of the Appalachian Mountains started 1.1 billion years ago. The first mountain range in the region was created when the continents of Laurentia and Amazonia collided, creating a supercontinent called Rodinia. The collision of these continents caused the rocks to be folded and faulted, creating the first mountains in the region. Many of the rocks and minerals that were formed during that event can currently be seen at the surface of the present Appalachian range. Around 480 million years ago, geologic processes began that led to three distinct orogenic eras that created much of the surface structure seen in today's Appalachians. Шаблон:Efn During this period, mountains once reached elevations similar to those of the Alps and the Rockies before natural erosion occurred over the last 240 million years leading to what is present today.

The Appalachian Mountains are a barrier to east–west travel, as they form a series of alternating ridgelines and valleys oriented in opposition to most highways and railroads running east–west. This barrier was extremely important in shaping the expansion of the United States in the colonial era.

The range is the home of a very popular recreational feature, the Appalachian Trail. This is a Шаблон:Convert hiking trail that runs all the way from Mount Katahdin in Maine to Springer Mountain in Georgia, passing over or past a large part of the Appalachian range. The International Appalachian Trail is an extension of this hiking trail into the Canadian portion of the Appalachian range in New Brunswick and Quebec.

Etymology

While exploring inland along the northern coast of Florida in 1528, the members of the Narváez expedition, including Álvar Núñez Cabeza de Vaca, found a Native American village near present-day Tallahassee, Florida whose name they transcribed as Apalchen or Apalachen Шаблон:IPA-all. The name was soon altered by the Spanish to Apalachee and used as a name for the tribe and region spreading well inland to the north. Pánfilo de Narváez's expedition first entered Apalachee territory on June 15, 1528, and applied the name. Now spelled "Appalachian", it is the fourth-oldest surviving European place-name in the US.

After the 1540 expedition of Hernando de Soto, Spanish cartographers began to apply the name of the tribe to the mountains themselves. The first cartographic appearance of Apalchen is on Diego Gutiérrez's map of 1562; the first use for the mountain range is the map of Jacques le Moyne de Morgues in 1565.

Файл:Gutierrez-1562-detail-app1.jpg

Diego Gutiérrez's 1562 map of the Western Hemisphere showing the first known use of a variation of the place name Appalachia ("Apalchen") from his map, Шаблон:Lang

The name was not commonly used for the whole mountain range until the late 19th century. A competing and often more popular name was the "Allegheny Mountains", "Alleghenies", and even "Alleghania". In the early 19th century, Washington Irving proposed renaming the United States either Appalachia or Alleghania.

In U.S. dialects in the southern regions of the Appalachians, the word is pronounced Шаблон:IPAc-en, with the third syllable sounding like "latch". In northern parts of the mountain range, it is pronounced Шаблон:IPAc-en or Шаблон:IPAc-en; the third syllable is like "lay", and the fourth "chins" or "shins". There is often great debate between the residents of the regions regarding the correct pronunciation. Elsewhere, a commonly accepted pronunciation for the adjective Appalachian is Шаблон:IPAc-en, with the last two syllables "-ian" pronounced as in the word "Romanian".

Geography

Файл:Appalachian Mountains of North America.jpg

Appalachian Mountains broken down by physiographic division, provinces, and sections.

Perhaps partly because the range runs through large portions of both the United States and Canada, and partly because the range was formed over numerous geologic time periods (one of which is sometimes termed the Appalachian orogeny), writing communities struggle to agree on an encyclopedic definition of the mountain range. However, each of the governments has an agency that informs the public about the major landforms that make up the countries - the United States Geological Survey (USGS) and the Geological Survey of Canada (GSC). The landforms are referred to as physiographic regions. The regions create precise boundaries from which maps can be drawn. The Appalachian Highlands is the name one of the eight physiographic regions of the contiguous 48 United States. The Appalachian Uplands is the name of one of seven physiographic regions of Canada.

Appalachian Highlands of the United States

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Appalachian Highlands physiographic provinces.

The second level in the physiographic classification schema for the USGS is "province" (unfortunately the same word as Canada uses to divide its political subdivisions - meaning that the terminology used by the two countries do not match below the region level). The lowest level of classification is "section". Following are the physiographic provinces and sections of the Appalachian Highlands using USGS terminology.

Appalachian Uplands of Canada

Файл:Appalachian Uplands by SubRegion.jpg

Appalachian Uplands of Canada with 13 divisions as defined by CGS.

The Appalachian Uplands are one of the seven physiographic divisions in Canada. Canada's GSC does not use the same classification system as the USGS below the division level. The agency does break the divisions of the Appalachian Uplands into 13 subsections that are in four different political provinces of Canada.

Шаблон:Bulleted list.

While the Appalachian Highlands and Appalachian Uplands are generally continuous across the U.S./Canadian border, the St. Lawrence Valley area is handled differently in the physiographic classification schemas. The part of the St. Lawrence Valley in the United States is one of the second-level classifications, part of the Appalachian Highlands. In Canada, the area is part of the first-level classification, the St. Lawrence Lowlands. This includes the area around the city of Montreal, Anticosti Island, and the northwest coastline of Newfoundland. The dissected plateau area, while not actually made up of geological mountains, is popularly called "mountains", especially in eastern Kentucky and West Virginia, and while the ridges are not high, the terrain is extremely rugged. In Ohio and New York, some of the plateau has been glaciated, which has rounded off the sharp ridges and filled the valleys to some extent. The glaciated regions are usually referred to as hill country rather than mountains.

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Notre-Dame Range, hills belonging to the Appalachian Mountains, Quebec, Canada

Range Characteristics

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The Appalachian Trail at Mount Minsi, Pennsylvania

The Appalachian belt includes the plateaus sloping southward to the Atlantic Ocean in New England, and southeastward to the border of the coastal plain through the central and southern Atlantic states; and on the northwest, the Allegheny and Cumberland plateaus declining toward the Great Lakes and the interior plains. A remarkable feature of the belt is the longitudinal chain of broad valleys, including the Great Appalachian Valley, which in the southerly sections divides the mountain system into two unequal portions, but in the northernmost lies west of all the ranges possessing typical Appalachian features, and separates them from the Adirondack group. The mountain system has no axis of dominating altitudes, but in every portion, the summits rise to rather uniform heights, and, especially in the central section, the various ridges and intermontane valleys have the same trend as the system itself. None of the summits reaches the region of perpetual snow.

In Pennsylvania, there are over sixty summits that rise over Шаблон:Convert; the summits of Mount Davis and Blue Knob rise over Шаблон:Convert. In Maryland, Eagle Rock and Dans Mountain are conspicuous points reaching Шаблон:Convert and Шаблон:Convert respectively. On the same side of the Great Valley, south of the Potomac, are the Pinnacle Шаблон:Convert and Pidgeon Roost Шаблон:Convert. In West Virginia, more than 150 peaks rise above Шаблон:Convert, including Spruce Knob Шаблон:Convert, the highest point in the Allegheny Mountains. A number of other points in the state rise above Шаблон:Convert. Cheat Mountain (Snowshoe Mountain) at Thorny Flat Шаблон:Convert and Bald Knob Шаблон:Convert are among the more notable peaks in West Virginia.

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Part of the Appalachian Mountains as seen from the international space station.

The Blue Ridge Mountains, rising in southern Pennsylvania and there known as South Mountain, attain elevations of about Шаблон:Convert in that state. South Mountain achieves its highest point just below the Mason-Dixon line in Maryland at Quirauk Mountain Шаблон:Convert and then diminishes in height southward to the Potomac River. Once in Virginia, the Blue Ridge again reaches Шаблон:Convert and higher. In the Virginia Blue Ridge, the following are some of the highest peaks north of the Roanoke River: Stony Man Шаблон:Convert, Hawksbill Mountain Шаблон:Convert, Apple Orchard Mountain Шаблон:Convert and Peaks of Otter Шаблон:Convert. South of the Roanoke River, along the Blue Ridge, are Virginia's highest peaks including Whitetop Mountain Шаблон:Convert and Mount Rogers Шаблон:Convert, the highest point in the Commonwealth.

Chief summits in the southern section of the Blue Ridge are located along two main crests—the Western or Unaka Front along the Tennessee-North Carolina border and the Eastern Front in North Carolina—or one of several "cross ridges" between the two main crests. Major subranges of the Eastern Front include the Black Mountains, Great Craggy Mountains, and Great Balsam Mountains, and its chief summits include Grandfather Mountain Шаблон:Convert near the Tennessee-North Carolina border, Mount Mitchell Шаблон:Convert in the Blacks, and Black Balsam Knob Шаблон:Convert and Cold Mountain Шаблон:Convert in the Great Balsams. The Western Blue Ridge Front is subdivided into the Unaka Range, the Bald Mountains, the Great Smoky Mountains, and the Unicoi Mountains, and its major peaks include Roan Mountain Шаблон:Convert in the Unakas, Big Bald Шаблон:Convert and Max Patch Шаблон:Convert in the Bald Mountains, Clingmans Dome Шаблон:Convert, Mount Le Conte Шаблон:Convert, and Mount Guyot Шаблон:Convert in the Great Smokies, and Big Frog Mountain Шаблон:Convert near the Tennessee-Georgia-North Carolina border. Prominent summits in the cross ridges include Waterrock Knob (Шаблон:Convert) in the Plott Balsams. Across northern Georgia, numerous peaks exceed Шаблон:Convert, including Brasstown Bald, the state's highest, at Шаблон:Convert and Шаблон:Convert Rabun Bald. In north-central Alabama, Mount Cheaha rises prominently to Шаблон:Convert over its surroundings, as part of the southernmost spur of the Blue Ridge Mountains.

Highest Peaks in each U.S. state and Canadian province in the Appalachian Mountains

State or Province	Country	Physiographic Area	Highest Peak	Elev. (feet)	Elev. (meters)	Geographic Coordinates
Alabama	USA	Appalachian Plateau	Cheaha Mountain	2,407	734	33.4869° N 85.8091° W
Georgia	USA	Blue Ridge	Brasstown Bald	4,784	1,457	34.8745° N 83.8063° W
Kentucky	USA	Appalachian Plateau	Black Mountain	4,145	1,263	36.9022° N 82.9144° W
Maine	USA	New England	Mount Katahdin	5,269	1,606	45.9046° N 68.9216° W
Maryland	USA	Appalachian Plateau	Backbone Mountain	3,360	1,024	39.4049° N 79.2911° W
New Brunswick	Canada	Chaleur Uplands	Mount Carleton	2,690	820	47.2241° N 66.5233 ° W
Newfoundland	Canada	Newfoundland	The Cabox	2,664	812	48.4959° N 58.2903° W
New Hampshire	USA	New England	Mount Washington	6,288	1,917	44.1614° N 71.1811° W
New York	USA	Adirondacks	Mount Marcy	5,344	1,629	44.1126° N 73.9235° W
North Carolina	USA	Blue Ridge	Mount Mitchell	6,684	2,037	35.7658° N 82.2655° W
Nova Scotia	Canada	Nova Scotia Highlands	White Hill	1,755	535	46.7555° N 60.6350° W
Ohio	USA	Appalachian Plateau	Campbell Hill	1,549	472	40.3888° N 83.6381° W
Pennsylvania	USA	Appalachian Plateau	Mount Davis	3,213	979	39.7866° N 79.1751° W
South Carolina	USA	Blue Ridge	Sassafras Mountain	3,553	1,083	35.0632° N 82.3062° W
Tennessee	USA	Blue Ridge	Clingmans Dome	6,643	2,025	35.5625° N 83.4989° W
Virginia	USA	Blue Ridge	Mount Rogers	5,729	1,746	36.6586° N 81.5438° W
West Virginia	USA	Appalachian Plateau	Spruce Knob	4,863	1,482	38.6992° N 79.5327° W

Description of Appalachian Mountains divided into three sections

Sources written prior to the recognition of the physiographic region concept divided the Appalachian Mountains into three major sections:Шаблон:Efn

Файл:Mt. Washington from Bretton Woods.JPG

Mt. Washington, NH from Bretton Woods

• Northern: The northern section runs from the Canadian province of Newfoundland and Labrador to the Hudson River. It includes the Long Range Mountains and Annieopsquotch Mountains on the island of Newfoundland, the French Territorial Collectivity of Saint-Pierre and Miquelon southwest of Newfoundland, Chic-Choc Mountains and Notre Dame Range in Quebec and New Brunswick, scattered elevations and small ranges elsewhere in Nova Scotia and New Brunswick, the Longfellow Mountains in Maine, the White Mountains in New Hampshire, the Green Mountains in Vermont, and The Berkshires in Massachusetts, and Connecticut, the Metacomet Ridge Mountains in Connecticut and south-central Massachusetts, and the Adirondack Mountains in New York are all part of the Appalachian Mountains as defined by the governments of Canada and the United States.

Mountains of the Long Range in Newfoundland, such as the Cabox and Gros Morne, reach heights of nearly Шаблон:Convert. In the Chic-Choc and Notre Dame Mountain ranges in Quebec, the higher summits rise above Шаблон:Convert in elevation. Isolated peaks and small ranges in Nova Scotia and New Brunswick vary from Шаблон:Convert. In Maine, several peaks exceed Шаблон:Convert, including Mount Katahdin at Шаблон:Convert. In New Hampshire, many summits rise above Шаблон:Convert, including Mount Washington in the White Mountains at Шаблон:Convert, Adams at Шаблон:Convert, Jefferson at Шаблон:Convert, Monroe at Шаблон:Convert, Madison at Шаблон:Convert, Lafayette at Шаблон:Convert, and Lincoln at Шаблон:Convert. In the Green Mountains the highest point, Mt. Mansfield, is Шаблон:Convert in elevation; others include Killington Peak at Шаблон:Convert, Camel's Hump at Шаблон:Convert, Mt. Abraham at Шаблон:Convert, and a number of other heights exceeding Шаблон:Convert.

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Shaded map of the Cumberland Plateau and Ridge-and-Valley Appalachians on the Virginia–West Virginia border

• Central: The central section runs from the Hudson Valley in New York to the New River through the Lehigh Valley and central Pennsylvania and western Maryland to western Virginia and West Virginia. The central region comprises the Valley Ridges between the Allegheny Front of the Allegheny Plateau and the Great Appalachian Valley, the New York–New Jersey Highlands, the Taconic Mountains in New York, and a large portion of the Blue Ridge. In addition to the true folded mountains, known as the ridge and valley province, the area of dissected plateau to the north and west of the mountains is usually grouped with the Appalachians. This includes the Catskill Mountains of Lower New York, the Poconos in Pennsylvania, and the Allegheny Plateau of New York's Southern Tier region, western Pennsylvania, eastern Ohio and northern West Virginia.

Файл:Greene-county-bald-mtns-tn1.jpg

Bald Mountains in Tennessee

• Southern: The southern section runs from the New River and consists of the prolongation of the Blue Ridge Mountains, which is divided into the Western Blue Ridge (or Unaka) Front and the Eastern Blue Ridge Front, the Ridge-and-Valley Appalachians, and the Cumberland Plateau. This same plateau is known as the Cumberland Plateau in southern West Virginia, eastern Kentucky, far Southwest Virginia, eastern Tennessee, and northern Alabama.

Geology

Шаблон:Main Plate tectonics over the period dating back at least 1 billion years led to geological creation of the land that is now the Appalachian Mountain range. The continental movement led to collisions that built mountains and they later pulled apart creating oceans over parts of the continent that are now exposed.

Grenville Orogeny and formation of Supercontinent Rodinia

The first mountain-building tectonic plate collision that initiated the construction of what are today the Appalachians occurred at least a billion years ago when the pre-North American craton called Laurentia collided with at least one other craton - Amazonia. All the other cratons of the earth also collided at about this time to form the supercontinent Rodinia and were surrounded by one single ocean. (It is possible that the cratons of Kalahari, and Rio Plato, were also part of that early collision since they were present as Rodinia broke up). Mountain-building referred to as the Grenville Orogeny occurred along the boundaries of the cratons. The present Appalachian Mountains have at least two areas which are made from rock formations that were formed during this orogeny - the Blue Ridge Mountains and the Adirondacks.

Файл:Grenville extent.gif

Land added to Laurentia during the Grenville orogeny.

Breakup of Rodinia and formation of the Iapetus Ocean

After the Grenville orogeny, the direction of the continental drift reversed, and the single supercontinent Rodinia began to break up. The mountains formed during the Grenvillian era underwent erosion due to weathering, glaciation, and other natural processes, resulting in the leveling of the landscape. The eroded sediments from these mountains contributed to the formation of sedimentary basins and valleys. For example, in what is now the southern United States, the Ococee Basin was formed. Seawater filled the basin. Rivers from the surrounding countryside carried clay, silt, sand, and gravel to the basin, much as rivers today carry sediment from the midcontinent region to the Gulf of Mexico. The sediment spread out in layers on the basin floor. The basin continued to subside, and over a long period of time, probably millions of years, a great thickness of sediment accumulated. Eventually, the tectonic forces pulling the two continents apart became so strong that an ocean formed off the eastern coast of the Laurentian margin. This was called the Iapetus Ocean and was the precursor of the modern Atlantic Ocean. The rocks of the Valley and Ridge province formed over millions of years, in the Iapetus. Shells and other hard parts of ancient marine plants and animals accumulated to form limey deposits that later became limestone. This is the same process by which limestone forms in modern oceans. The weathering of limestone, now exposed at the land surface, produces the lime-rich soils that are so prevalent in the fertile farmland of the Valley and Ridge province.

During this continental break-up, around 600 million to 560 million years ago, volcanic activity was present along the tectonic margins. There is evidence of this activity in today's Blue Ridge Mountains. Mount Rogers, Whitetop Mountain, and Pine Mountain are all the result of volcanic activity that occurred around this time. Evidence of subsurface activity, dikes and sills intruding into the overlying rock, is present in the Blue Ridge as well. For instance, mafic rocks have been found along the Fries Fault in the central Blue Ridge area of Montgomery County, VA.

Taconic Orogeny

Файл:Taconic orogeny.gif

The Iapetus continued to expand and during that time bacteria, algae, and many species of invertebrates flourished in the oceans, but there were no plants or animals on land. Then, during the middle Ordovician Period about 500 to 470 million years ago, the motion of the crustal plates changed, and the continents began to move back toward each other. The once-quiet Appalachian passive margin changed to a very active plate boundary when a neighboring Iapetus oceanic plate containing a volcanic arc collided with and began sinking beneath the North American craton. Volcanoes grew along the continental margin coincident with the initiation of subduction. Thrust faulting uplifted and warped older sedimentary rock laid down on the passive margin. As the mountains rose, erosion began to wear them down over time. Streams carried rock debris downslope to be deposited in nearby lowlands. The Taconic orogeny ended after about 60 million years, but built much of the land mass that is now New England and southwestward to Pennsylvania.

The Taconic Orogeny was the second of four mountain building plate collisions that contributed to the formation of the Appalachians, culminating in the collision of North America and Africa (see Alleghanian orogeny).

Acadian Orogeny

The third mountain-building event was the Acadian orogeny which occurred between 375 and 359 million years ago. The Acadian orogeny was caused by a series of collisions of pieces of crust from the Avalonia Terrane, sections broken off from continent of Gondwana, with the North American Plate. The collision initiating this orogeny resulted in the closing of the southern Iapetus ocean and the formation of a high mountain belt. After the Acadian collision took place, Gondwana began to retreat from Laurentia with the newly accreted Avalonian terranes left behind. As Gondwana moved away, a new ocean opened up, the Rheic Ocean, during the Middle to Late Devonian, and subsequently its closure would result in the formation of the Alleghanian orogeny.

Alleghenian Orogeny and Supercontinent Pangea

As the continental plates moved closer together, fragments of oceanic crust, islands, and other continental masses collided with the eastern margin of ancestral North America. By this time, plants had appeared on land, followed by scorpions, insects, and amphibians. The ocean continued to shrink until, about 270 million years ago, the continents that were ancestral to North America and Africa collided during the formation of the supercontinent Pangea.

Because North America and Africa were connected, the Appalachians formed part of the same mountain chain as the Little Atlas in Morocco. This mountain range, known as the Central Pangean Mountains, extended into Scotland, before the Mesozoic Era opening of the Iapetus Ocean, from the North America/Europe collision (See Caledonian orogeny).

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Old fault exposed by roadcut near Hazleton, Pennsylvania, along Interstate 81 include faults that are common in the folded Appalachians.

By the end of the Mesozoic Era, the Appalachian Mountains had been eroded to an almost flat plain. It was not until the region was uplifted during the Cenozoic Era that the distinctive topography of the present formed. Uplift rejuvenated the streams, which rapidly responded by cutting downward into the ancient bedrock. Some streams flowed along weak layers that define the folds and faults created many millions of years earlier. Other streams downcut so rapidly that they cut right across the resistant folded rocks of the mountain core, carving canyons across rock layers and geologic structures.

Mineral resources

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Cliffs overlooking the New River near Gauley Bridge, West Virginia

The Appalachian Mountains contain major deposits of anthracite coal as well as bituminous coal. In the folded mountains the coal is in metamorphosed form as anthracite, represented by the Coal Region of northeastern Pennsylvania. The bituminous coal fields of western Pennsylvania, western Maryland, southeastern Ohio, eastern Kentucky, southwestern Virginia, and West Virginia contain the sedimentary form of coal. The mountain top removal method of coal mining, in which entire mountain tops are removed, is currently threatening vast areas and ecosystems of the Appalachian Mountain region. The surface coal mining that started in the 1940s has significantly impacted the central Appalachian Mountains in Kentucky, Tennessee, Virginia and West Virginia. Early mining methods were unregulated and mined land reclamation research, including acid base reaction, was led by the West Virginia University in the 1960s and 1970s. West Virginia developed rigorous mine reclamation standards for state coal mines in the late 1960s. Regulations were introduced by most federal states to protect the Appalachian Mountains by the late 1960s. Social and political activism brought about the Surface Mining Control and Reclamation Act of 1977.

The 1859 discovery of commercial quantities of petroleum in the Appalachian Mountains of western Pennsylvania started the modern United States petroleum industry. Recent discoveries of commercial natural gas deposits in the Marcellus Shale formation and Utica Shale formations have once again focused oil industry attention on the Appalachian Basin.

Some plateaus of the Appalachian Mountains contain metallic minerals such as iron and zinc.

Drainage

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Paleogeographic reconstruction showing the Appalachian Basin area during the Middle Devonian period

There are many geological issues concerning the rivers and streams of the Appalachians. In spite of the existence of the Great Appalachian Valley, many of the main rivers are transverse to the mountain system axis. The drainage divide of the Appalachians follows a tortuous course that crosses the mountainous belt just north of the New River in Virginia. South of the New River, rivers head into the Blue Ridge, cross the higher Unakas, receive important tributaries from the Great Valley, and traversing the Cumberland Plateau in spreading gorges (water gaps), escape by way of the Cumberland River and the Tennessee River rivers to the Ohio River and the Mississippi River, and thence to the Gulf of Mexico. In the central section, north of the New River, the rivers, rising in or just beyond the Valley Ridges, flow through great gorges to the Great Valley, and then across the Blue Ridge to tidal estuaries penetrating the coastal plain via the Roanoke River, James River, Potomac River, and Susquehanna River.

In the northern section the height of land lies on the inland side of the mountainous belt, and thus the main lines of drainage run from north to south, exemplified by the Hudson River. However, the valley through which the Hudson River flows was cut by the gigantic glaciers of the ice ages—the same glaciers that deposited their terminal moraines in southern New York and formed the east–west Long Island.

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Apple Orchard Mountain peak in the Blue Ridge Mountains, which stretch from southern Pennsylvania in the north through Georgia in the south

The Appalachian region is generally considered the geographical divide between the eastern seaboard of the United States and the Midwest region of the country. The Eastern Continental Divide follows the Appalachian Mountains from Pennsylvania to Georgia.

Ecology

The Appalachians, particularly the Central and Southern regions, is one of the most biodiverse places in North America. The north–south orientation of the long ridges and valleys contributes to the high number of plant and animal species. Species were able to migrate through these from either direction during alternating periods of warming and cooling, settling in the microclimates that best suited them.

Flora

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View from Mount Mitchell, North Carolina at Шаблон:Convert, the highest peak east of the Mississippi River

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Shenandoah National Park in Virginia

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View from Craggy Gardens on the Blue Ridge Parkway in North Carolina

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Great laurel thicket in the Pisgah National Forest in North Carolina

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Cranberry Glades, a bog preserve in West Virginia

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Grassy balds on the Roan Highlands straddling the North Carolina/Tennessee border

The flora of the Appalachians are diverse and vary primarily in response to geology, latitude, elevation and moisture availability. Geobotanically, they constitute a floristic province of the North American Atlantic Region. The Appalachians consist primarily of deciduous broad-leaf trees and evergreen needle-leaf conifers, but also contain the evergreen broad-leaf American holly (Шаблон:Lang), and the deciduous needle-leaf conifer, the tamarack, or eastern larch (Шаблон:Lang).

The dominant northern and high elevation conifer is the red spruce (Шаблон:Lang), which grows from near sea level to above Шаблон:Convert above sea level (asl) in northern New England and southeastern Canada. It also grows southward along the Appalachian crest to the highest elevations of the southern Appalachians, as in North Carolina and Tennessee. In the central Appalachians it is usually confined above Шаблон:Convert asl, except for a few cold valleys in which it reaches lower elevations. In the southern Appalachians, it is restricted to higher elevations. Another species is the black spruce (Шаблон:Lang), which extends farthest north of any conifer in North America, is found at high elevations in the northern Appalachians, and in bogs as far south as Pennsylvania.

The Appalachians are also home to two species of fir, the boreal balsam fir (Шаблон:Lang), and the southern high elevation endemic, Fraser fir (Шаблон:Lang). Fraser fir is confined to the highest parts of the southern Appalachian Mountains, where along with red spruce it forms a fragile ecosystem known as the Southern Appalachian spruce–fir forest. Fraser fir rarely occurs below Шаблон:Convert, and becomes the dominant tree type at Шаблон:Convert. By contrast, balsam fir is found from near sea level to the tree line in the northern Appalachians, but ranges only as far south as Virginia and West Virginia in the central Appalachians, where it is usually confined above Шаблон:Convert asl, except in cold valleys. Curiously, it is associated with oaks in Virginia. The balsam fir of Virginia and West Virginia is thought by some to be a natural hybrid between the more northern variety and Fraser fir. While red spruce is common in both upland and bog habitats, balsam fir, as well as black spruce and tamarack, are more characteristic of the latter. However, balsam fir also does well in soils with a pH as high as 6.

Eastern or Canada hemlock (Шаблон:Lang) is another important evergreen needle-leaf conifer that grows along the Appalachian chain from north to south but is confined to lower elevations than red spruce and the firs. It generally occupies richer and less acidic soils than the spruce and firs and is characteristic of deep, shaded and moist mountain valleys and coves. It is, unfortunately, subject to the hemlock woolly adelgid (Шаблон:Lang), an introduced insect, that is rapidly extirpating it as a forest tree. Less abundant, and restricted to the southern Appalachians, is Carolina hemlock (Шаблон:Lang). Like Canada hemlock, this tree suffers severely from the hemlock woolly adelgid.

Several species of pines characteristic of the Appalachians are eastern white pine (Шаблон:Lang), Virginia pine (Шаблон:Lang), pitch pine (Шаблон:Lang), Table Mountain pine (Шаблон:Lang) and shortleaf pine (Шаблон:Lang). Red pine (Шаблон:Lang) is a boreal species that forms a few high elevation outliers as far south as West Virginia. All of these species except white pine tend to occupy sandy, rocky, poor soil sites, which are mostly acidic in character. White pine, a large species valued for its timber, tends to do best in rich, moist soil, either acidic or alkaline in character. Pitch pine is also at home in acidic, boggy soil, and Table Mountain pine may occasionally be found in this habitat as well. Shortleaf pine is generally found in warmer habitats and at lower elevations than the other species. All the species listed do best in open or lightly shaded habitats, although white pine also thrives in shady coves, valleys, and on floodplains.

The Appalachians are characterized by a wealth of large, beautiful deciduous broadleaf (hardwood) trees. Their occurrences are best summarized and described in E. Lucy Braun's 1950 classic, Deciduous Forests of Eastern North America (Macmillan, New York). The most diverse and richest forests are the mixed-mesophytic or medium-moisture types, which are largely confined to rich, moist montane soils of the southern and central Appalachians, particularly in the Cumberland and Allegheny Mountains, but also thrive in the southern Appalachian coves. Characteristic canopy species are white basswood (Шаблон:Lang), yellow buckeye (Шаблон:Lang), sugar maple (Шаблон:Lang), American beech (Шаблон:Lang), tuliptree (Шаблон:Lang), white ash (Шаблон:Lang) and yellow birch (Шаблон:Lang). Other common trees are red maple (Шаблон:Lang), shagbark and bitternut hickories (Шаблон:Lang) and black or sweet birch (Шаблон:Lang). Small understory trees and shrubs include flowering dogwood (Шаблон:Lang), hophornbeam (Шаблон:Lang), witch-hazel (Шаблон:Lang) and spicebush (Шаблон:Lang). There are also hundreds of perennial and annual herbs, among them such herbal and medicinal plants as American ginseng (Шаблон:Lang), goldenseal (Шаблон:Lang), bloodroot (Шаблон:Lang) and black cohosh (Шаблон:Lang).

The foregoing trees, shrubs, and herbs are also more widely distributed in less rich mesic forests that generally occupy coves, stream valleys and flood plains throughout the southern and central Appalachians at low and intermediate elevations. In the northern Appalachians and at higher elevations of the central and southern Appalachians these diverse mesic forests give way to less diverse northern hardwood forests with canopies dominated only by American beech, sugar maple, American basswood (Шаблон:Lang) and yellow birch and with far fewer species of shrubs and herbs.

Drier and rockier uplands and ridges are occupied by oak–chestnut forests dominated by a variety of oaks (Шаблон:Lang spp.), hickories (Шаблон:Lang spp.) and, in the past, by the American chestnut (Шаблон:Lang). The American chestnut was virtually eliminated as a canopy species by the introduced fungal chestnut blight (Шаблон:Lang), but lives on as sapling-sized sprouts that originate from roots, which are not killed by the fungus. In present-day forest canopies, chestnut has been largely replaced by oaks.

The oak forests of the southern and central Appalachians consist largely of black, northern red, white, chestnut and scarlet oaks (Шаблон:Lang and Шаблон:Lang) and hickories, such as the pignut (Шаблон:Lang) in particular. The richest forests, which grade into mesic types, usually in coves and on gentle slopes, have predominantly white and northern red oaks, while the driest sites are dominated by chestnut oak, or sometimes by scarlet or northern red oaks. In the northern Appalachians the oaks, except for white and northern red, drop out, while the latter extends farthest north.

The oak forests generally lack the diverse small tree, shrub and herb layers of mesic forests. Shrubs are generally ericaceous, and include the evergreen mountain laurel (Шаблон:Lang), various species of blueberries (Шаблон:Lang spp.), black huckleberry (Шаблон:Lang), a number of deciduous rhododendrons (azaleas), and smaller heaths such as teaberry (Шаблон:Lang) and trailing arbutus (Шаблон:Lang). The evergreen great rhododendron (Шаблон:Lang) is characteristic of moist stream valleys. These occurrences are in line with the prevailing acidic character of most oak forest soils. In contrast, the much rarer chinquapin oak (Шаблон:Lang) demands alkaline soils and generally grows where limestone rock is near the surface. Hence no ericaceous shrubs are associated with it.

The Appalachian flora also include a diverse assemblage of bryophytes (mosses and liverworts), as well as fungi. Some species are rare and/or endemic. As with vascular plants, these tend to be closely related to the character of the soils and the thermal environment in which they are found.

Eastern deciduous forests are subject to a number of serious insect and disease outbreaks. Among the most conspicuous is that of the introduced gypsy moth (Шаблон:Lang), which infests primarily oaks, causing severe defoliation and tree mortality. But it also has the benefit of eliminating weak individuals, and thus improving the genetic stock, as well as creating rich habitat of a type through accumulation of dead wood. Because hardwoods sprout so readily, this moth is not as harmful as the hemlock woolly adelgid. Perhaps more serious is the introduced beech bark disease complex, which includes both a scale insect (Шаблон:Lang) and fungal components.

During the 19th and early 20th centuries, the Appalachian forests were subject to severe and destructive logging and land clearing, which resulted in the designation of the national forests and parks as well many state-protected areas. However, these and a variety of other destructive activities continue, albeit in diminished forms; and thus far only a few ecologically based management practices have taken hold.

Appalachian bogs are boreal ecosystems, which occur in many places in the Appalachians, particularly the Allegheny and Blue Ridge subranges. Though popularly called bogs, many of them are technically fens.

Several mountain summits in the southern Appalachians are covered with expansive open habitats (either grassy meadows or heath) known as Appalachian balds. These habitats support many unique plant and animal communities, including rare, relict species, that are adapted to the open, exposed habitat. Their origins are heavily debated; while all were formerly thought to have anthropogenic origins, more recent evidence indicates a mixed origin: many were formed by climatic conditions in the Pleistocene and kept open by Pleistocene megafauna, then by other grazing wildlife (such as bison, elk, and deer) and Native American burning practices, and finally by grazing livestock introduced by European settlers. Others, especially those dominated by introduced grasses, may be fully anthropogenic in origin. The abandonment of grazing has caused trees to encroach on many of these balds, threatening their ecosystems.

In contrast to the largely grazing-influenced balds of the southern Appalachians, parts of the northern Appalachians such as the White Mountains. the Adirondack Mountains, and Mount Katahdin have summits covered with true alpine tundra; these ecosystems are kept clear due to extremely harsh winter storms, and support a vegetation community more akin to that of the Arctic Circle.

Fauna

Файл:Southern Flying Squirrel-27527-3.jpg

Southern flying squirrel

Файл:Wild Turkey-27527-1.jpg

Male eastern wild turkey

Animals that characterize the Appalachian forests include five species of tree squirrels. The most commonly seen is the low to moderate elevation eastern gray squirrel (Шаблон:Lang). Occupying similar habitat is the slightly larger fox squirrel (Шаблон:Lang) and the much smaller southern flying squirrel (Шаблон:Lang). More characteristic of cooler northern and high elevation habitat is the red squirrel (Шаблон:Lang), whereas the Appalachian northern flying squirrel (Шаблон:Lang), which closely resembles the southern flying squirrel, is confined to northern hardwood and spruce–fir forests.

As familiar as squirrels are the eastern cottontail rabbit (Шаблон:Lang) and the white-tailed deer (Шаблон:Lang). The latter in particular has greatly increased in abundance as a result of the extirpation of the eastern wolf (Шаблон:Lang) and the North American cougar. This has led to the overgrazing and browsing of many plants of the Appalachian forests, as well as destruction of agricultural crops. Other deer include the moose (Шаблон:Lang), found only in the north, and the elk (Шаблон:Lang), which, although once extirpated, is now making a comeback, through transplantation, in the southern and central Appalachians. In Quebec, the Chic-Chocs host the only population of reindeer (Шаблон:Lang) south of the St. Lawrence River. An additional species that is common in the north but extends its range southward at high elevations to Virginia and West Virginia is the varying or snowshoe hare (Шаблон:Lang). However, these central Appalachian populations are scattered and very small.

Another species of great interest is the beaver (Шаблон:Lang), which is showing a great resurgence in numbers after its near extirpation for its pelt. This resurgence is bringing about a drastic alteration in habitat through the construction of dams and other structures throughout the mountains.

Other common forest animals are the black bear (Шаблон:Lang), striped skunk (Шаблон:Lang), raccoon (Шаблон:Lang), opossum (Шаблон:Lang), woodchuck (Шаблон:Lang), bobcat (Шаблон:Lang), gray fox (Шаблон:Lang), red fox (Шаблон:Lang) and in recent years, the coyote (Шаблон:Lang), another species favored by the advent of Europeans and the extirpation of eastern and red wolves (Шаблон:Lang). European boars (Шаблон:Lang) were introduced in the early 20th century.

Characteristic birds of the forest are wild turkey (Шаблон:Lang), ruffed grouse (Шаблон:Lang), mourning dove (Шаблон:Lang), common raven (Шаблон:Lang), wood duck (Шаблон:Lang), great horned owl (Шаблон:Lang), barred owl (Шаблон:Lang), screech owl (Шаблон:Lang), red-tailed hawk (Шаблон:Lang), red-shouldered hawk (Шаблон:Lang), and northern goshawk, as well as a great variety of "songbirds" (Passeriformes), like the warblers in particular.

Of great importance are the many species of salamanders and, in particular, the lungless species (Family Шаблон:Lang) that live in great abundance concealed by leaves and debris, on the forest floor. Most frequently seen, however, is the eastern or red-spotted newt (Шаблон:Lang), whose terrestrial eft form is often encountered on the open, dry forest floor. It has been estimated that salamanders represent the largest class of animal biomass in the Appalachian forests. Frogs and toads are of lesser diversity and abundance, but the wood frog (Шаблон:Lang) is, like the eft, commonly encountered on the dry forest floor, while a number of species of small frogs, such as spring peepers (Шаблон:Lang), enliven the forest with their calls. Salamanders and other amphibians contribute greatly to nutrient cycling through their consumption of small life forms on the forest floor and in aquatic habitats.

Although reptiles are less abundant and diverse than amphibians, a number of snakes are conspicuous members of the fauna. One of the largest is the non-venomous black rat snake (Шаблон:Lang), while the common garter snake (Шаблон:Lang) is among the smallest but most abundant. The Eastern copperhead (Шаблон:Lang) and the timber rattler (Шаблон:Lang) are venomous pit vipers. There are few lizards, but the broad-headed skink (Шаблон:Lang), at up to Шаблон:Convert in length, and an excellent climber and swimmer, is one of the largest and most spectacular in appearance and action. The most common turtle is the eastern box turtle (Шаблон:Lang), which is found in both upland and lowland forests in the central and southern Appalachians. Prominent among aquatic species is the large common snapping turtle (Шаблон:Lang), which occurs throughout the Appalachians.

Appalachian streams are notable for their highly diverse freshwater fish life. Among the most abundant and diverse are those of the minnow family (family Cyprinidae), while species of the colorful darters (Шаблон:Lang spp.) are also abundant.

A characteristic fish of shaded, cool Appalachian forest streams is the wild brook or speckled trout (Шаблон:Lang), which is much sought after as a game fish.

Appalachian Mountains' impact on North American History

Indigenous People

The roots of the Appalachian regions' histories trace back to the indigenous peoples who inhabited these lands long before European arrival. Indigenous communities across the Appalachians developed diverse cultures, languages, and societies, adapting to the region's varying environments and ecosystems. The interactions between indigenous communities and the natural world laid the foundation for the intricate relationship between humans and the Appalachian landscape. Indigenous peoples thrived in these challenging terrains, adapting their lifestyles to the resources available. They forged deep connections with the land, developing sustainable practices for hunting, fishing, agriculture, and gathering. The Appalachian landscape provided a rich tapestry of flora and fauna, which indigenous communities learned to harness for their sustenance and well-being. The Appalachian Mountains served as a conduit for trade networks, connecting distant indigenous communities through intricate trails. These trade routes facilitated the exchange of goods, ideas, and cultural practices across vast distances. This network fostered a sense of shared identity among diverse indigenous groups, transcending geographical boundaries.

European Exploration

During the late 15th and early 16th centuries, European explorers embarked on voyages of discovery across the Atlantic Ocean. While seeking new trade routes and riches, they encountered the vast landmass of North America, including the Appalachian regions. The mountains posed a formidable geographical obstacle that European explorers had to navigate. The French, British, and Spanish were among the major powers vying for dominance in the New World, and their interactions with indigenous communities and the Appalachian landscape shaped the course of history.

Colonial Settlements

The Appalachian Highlands and Lowlands became focal points for European colonial expansion. French and British explorers traversed the Appalachian Mountains as they established footholds in North America. The French established settlements in the Great Lakes region and Canada, while the British colonies stretched along the eastern seaboard of what would become the United States. The territorial ambitions of European powers set the stage for later conflicts such as the French and Indian War.

The British Proclamation of 1763 holds significance in both Canadian and American histories. In the United States, the proclamation aimed to curb westward expansion beyond the Appalachian Mountains to avoid conflicts with indigenous nations, leading to tensions between American colonists and the British Crown and contributing to the drive for independence. In Canada, the proclamation provided a framework for governing newly acquired French territories, including Quebec, to ensure stability and control over the region. The ramifications of the proclamation were multifaceted, reflecting the complex dynamics of colonial governance and indigenous relations.

Cultural Exchange and Identity

The Appalachian Mountains in both countries nurtured unique cultural identities that persist to this day. The isolation of these mountainous regions allowed for the development of distinctive music, folklore, and traditions. Appalachian music played a significant role in the broader evolution of American and Canadian music genres. While each side of the border has its own cultural expressions, the shared geographical features and historical interactions contributed to common threads of self-reliance, resilience, and connection to nature that characterize Appalachian culture.

Colonization and Frontier Expansion

European exploration of the Appalachian regions contributed to the mapping and understanding of the area's geographical features. Explorers documented the rugged terrain, dense forests, and abundant natural resources. Their observations shaped the perceptions of the Appalachian landscape and influenced subsequent settlement patterns and resource utilization. The range posed significant barriers to westward expansion, leaving an indelible mark on colonization efforts.

Cumberland Gap and Gaspé Peninsula

The Cumberland Gap, a prominent geographic feature, played a pivotal role in westward expansion in the United States. This passage through the Appalachian Mountains provided a route for pioneers seeking new opportunities beyond the mountains. Similarly, Canada had its own geographical passage, the Gaspé Peninsula, which facilitated exploration and trade in the Canadian Appalachian region. These passages were vital gateways that shaped the movement of people, ideas, and resources on both sides of the border. Шаблон:Cite encyclopedia

See also

• Шаблон:Cl
• Appalachia
• Appalachian League
• Appalachian Mountain Club
• Appalachian Trail
• Appalachian American
• List of subranges of the Appalachian Mountains

Sources

• Topographic maps and Geologic Folios of the United States Geological Survey
• Шаблон:Cite journal
• Шаблон:Cite journal

Further reading

• Brooks, Maurice (1965), The Appalachians: The Naturalist's America; illustrated by Lois Darling and Lo Brooks. Boston; Houghton Mifflin Company.
• Caudill, Harry M. (1963), Night Comes to the Cumberlands. Шаблон:ISBN.
• Constantz, George (2004), Hollows, Peepers, and Highlanders: an Appalachian Mountain Ecology (2nd edition). West Virginia University Press; Morgantown. 359 p.
• Olson, Ted (1998), Blue Ridge Folklife. University Press of Mississippi, 211 pages, Шаблон:ISBN.
• Rehder, John (2013) "Appalachian Folkways," Koxville: University of Tennessee Press.
• Chapters iii., iv. and v. of Miss E. C. Semple's American History and its Geographic Conditions (Boston, 1903).
• Weidensaul, Scott (2000), Mountains of the Heart: A Natural History of the Appalachians. Fulcrum Publishing, 288 pages, Шаблон:ISBN.
• Bailey Willis, The Northern Appalachians, and C. W. Hayes, The Southern Appalachians, both in National Geographic Monographs, vol. 9.

Appalachian flora and fauna-related journals

• Castanea, the journal of the Southern Appalachian Botanical Society.
• Banisteria, a journal devoted to the natural history of Virginia.
• The Journal of the Torrey Botanical Society.

External links

• Appalachian/Blue Ridge Forests images at bioimages.vanderbilt.edu (slow modem version)
• Appalachian Mixed Mesophytic Forests images at bioimages.vanderbilt.edu (slow modem version)
• University of Kentucky Appalachian Center (archived 8 May 2010)
• Forests of the Central Appalachians Project Detailed inventories of forest species at dozens of sites.