Ridge and swale, or in dunal areas dune and swale, is a

landform A landform is a land feature on the solid surface of the Earth or other planetary body. They may be natural or may be anthropogenic (caused or influenced by human activity). Landforms together make up a given terrain, and their arrangement ...

consisting of regular, parallel ridges alternating with marshy depressions. Ridge-and-swale landscapes are most commonly formed by the gradual movement of a

beach A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from Rock (geology), rock, such as sand, gravel, shingle beach, shingle, pebbles, etc., or biological s ...

, for example as a result of gradually fluctuating water levels, or the shifting

meander A meander is one of a series of regular sinuous curves in the Channel (geography), channel of a river or other watercourse. It is produced as a watercourse erosion, erodes the sediments of an outer, concave bank (cut bank, cut bank or river cl ...

s of a river. In the river context, ridge-and-swale landscapes are commonly formed by

scroll bar A scrollbar is an interaction technique or widget in which continuous text, pictures, or any other content can be scrolled in a predetermined direction (up, down, left, or right) on a computer display, window, or viewport so that all of the c ...

s. They are also found along ocean coasts, for example on the

Outer Banks The Outer Banks (frequently abbreviated OBX) are a string of barrier islands and spits off the coast of North Carolina and southeastern Virginia, on the east coast of the United States. They line most of the North Carolina coastline, separatin ...

of North Carolina.

Great Lakes ridge and swale

Freshwater ridge-and-swale ecosystems are globally rare and found only in parts of the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, H ...

of North America. They were formed as a result of the gradual retreat of beaches due to falling water levels and

post-glacial rebound Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the removal of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression. Post-glacial rebound an ...

. The swales and the adjoining lake or river commonly form a single hydrological unit, so that rising or falling lake levels will cause water levels in the swales to rise or fall as well. Most ridge-and-swale landscapes have been destroyed as a result of the massive industrial development found in many former ridge-and-swale areas, such as the

Calumet Region The Calumet Region is the geographic area drained by the Grand Calumet River and the Little Calumet River of northeastern Illinois and northwestern Indiana in the United States. It is part of the Great Lakes Basin, which eventually reaches th ...

of Northwest Indiana. However, some extensive dune-and-swale complexes persist in Michigan, such as at the

Michigan Wilderness State Park Wilderness State Park is a public recreation area bordering Lake Michigan, five miles southwest of Mackinaw City in Emmet County in Northern Michigan. The state park's include of shoreline, diverse forested dune and swale complexes, wetlands, ...

. The remaining dune-and-swale complexes along the Great Lakes are often home to extremely rare plants and animals, such as the endangered Karner Blue butterfly. In the Calumet Region, the difficulty of moving equipment through dune-and-swale topography greatly slowed industrial development, but could not stop it after the turn of the 20th century. The few remnants are preserved as nature preserves, including the

Gibson Woods Gibson, Gibson's or Gibsons may refer to: Business * Gibson Appliance, a former American refrigerator manufacturer * Gibson (guitar company), an American manufacturer of guitars, other musical instruments, and audio equipment * Gibson Greetings, ...

county park in

Hessville, Indiana Hessville is a neighborhood of Hammond, Indiana Hammond ( ) is a city in Lake County, Indiana, United States. Located along Lake Michigan, it is part of the Chicago metropolitan area and the only city in Indiana to border Chicago. As of the 202 ...

, the Miller Woods section of the

Indiana Dunes National Park Indiana Dunes National Park is a List of national parks of the United States, national park of the United States located in northwestern Indiana managed by the National Park Service. It was authorized by Congress in 1966 as the Indiana Dunes Na ...

, and additional preserves operated by

The Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia, United States. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in ...

and

Shirley Heinze Land Trust The Shirley Heinze Land Trust, originally known as the Shirley Heinze Environmental Fund, is a 501(c)(3) nonprofit land trust dedicated to the preservation of natural areas in Northwest Indiana. The Heinze Trust manages more than 4,000 acres of ...

Great Lakes ridge and swale

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