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Lake Shetek State Park
A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a depression (geology), basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from the ocean, although they may be connected with the ocean by rivers. Lakes, as with other bodies of water, are part of the water cycle, the processes by which water moves around the Earth. Most lakes are fresh water and account for almost all the world's surface freshwater, but some are salt lakes with salinities even higher than that of seawater. Lakes vary significantly in surface area and volume of water. Lakes are typically larger and deeper than ponds, which are also water-filled basins on land, although there are no official definitions or scientific criteria distinguishing the two. Lakes are also distinct from lagoons, which are generally shallow tidal pools dammed by sandbars or other material at coastal regions ...
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Works Progress Administration
The Works Progress Administration (WPA; from 1935 to 1939, then known as the Work Projects Administration from 1939 to 1943) was an American New Deal agency that employed millions of jobseekers (mostly men who were not formally educated) to carry out public works projects, including the construction of public buildings and roads. It was set up on May 6, 1935, by presidential order, as a key part of the Second New Deal. The WPA's first appropriation in 1935 was $4.9 billion (about $15 per person in the U.S., around 6.7 percent of the 1935 GDP). Headed by Harry Hopkins, the WPA supplied paid jobs to the unemployed during the Great Depression in the United States, while building up the public infrastructure of the US, such as parks, schools, and roads. Most of the jobs were in construction, building more than of streets and over 10,000 bridges, in addition to many airports and much housing. In 1942, the WPA played a key role in both building and staffing Internment of Japanes ...
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Inholding
An inholding is privately owned land inside the boundary of a national park, national forest, state park, or similar publicly owned, protected area. In-holdings result from private ownership of lands predating the designation of the park or forest area, or the expansion of the park area to encompass the privately owned property. In the United States, the main causes of inholdings is that all of the Federal land-management agencies were formed over a century after the government sold and issued land grants to private citizens to fund the administration of the United States. When the park system was formed, many of these now-called "inholdings" had been in private ownership for generations and not available for sale when the park was formed. Over the last several decades, conservation groups have lobbied the United States Congress to acquire private residences especially within designated wilderness areas, either by direct purchase or via land exchange which trades the inh ...
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Northern Hardwood Forest
The northern hardwood forest is a general type of North American forest ecosystem found over much of southeastern and south-central Canada, Ontario, and Quebec, extending south into the United States in northern New England, New York, and Pennsylvania, and west along the Great Lakes to Minnesota and western Ontario. Some ecologists consider it a transitional forest because it contains species common to both the oak-hickory forest community to the south and the Boreal forest community to the north. The trees and shrub species of the Northern Hardwood Forest are known for their brilliant fall colors, making the regions that contain this forest type popular fall foliage tourist destinations. Sugar maple, yellow birch, American beech, and white ash are the common key indicator tree and shrub species in the Northern Hardwood Forest. Other species include eastern hemlock and eastern white pine. Herb and heath species include wintergreen, wild sarsaparilla, and wood sorrel. Bir ...
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Old Field (ecology)
Old field is a term used in ecology to describe lands formerly cultivated or grazed but later abandoned. The dominant flora include perennial grasses, Ericaceae, heaths and herbaceous plants. Old fields are canonically defined as an intermediate stage found in ecological succession in an ecosystem advancing towards its climax community, a concept which has been debated by contemporary ecologists for some time. Old field sites are often marginal lands with soil quality unsuitable for crops or pasture. Examples include abandoned farmlands in central Ontario, along the edge of the Canadian Shield. Stress tolerant species with wide seed dispersal ranges are able to colonize cultivated fields after their initial abandonment, usually followed by perennial grasses. The succession of old fields culminates in takeover by trees and shrubs, eventually leading to a climax forest stand. How old fields form Most old fields form as a result of agricultural land abandonment, the rate of which h ...
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Ecological Succession
Ecological succession is the process of how species compositions change in an Community (ecology), ecological community over time. The two main categories of ecological succession are primary succession and secondary succession. Primary succession occurs after the initial Colonisation (biology), colonization of a newly created habitat with no living organisms. Secondary succession occurs after a Disturbance (ecology), disturbance such as fire, habitat destruction, or a natural disaster destroys a pre-existing community. Both consistent patterns and variability are observed in ecological succession. Theories of ecological succession identify different factors that help explain why plant communities change the way they do. Succession was among the first theories advanced in ecology. Ecological succession was first documented in the Indiana Dunes of Northwest Indiana by Henry Chandler Cowles during the late 19th century and remains a main Ecology, ecological topic of study. Over ti ...
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Wildfire
A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a bushfire (Bushfires in Australia, in Australia), desert fire, grass fire, hill fire, Peat#Peat fires, peat fire, prairie fire, vegetation fire, or veld fire. Some natural forest ecosystems Fire ecology, depend on wildfire. Modern forest management often engages in prescribed burns to mitigate fire risk and promote natural forest cycles. However, controlled burns can turn into wildfires by mistake. Wildfires can be classified by cause of ignition, physical properties, combustible material present, and the effect of weather on the fire. Wildfire severity results from a combination of factors such as available fuels, physical setting, and weather. Climatic cycles with wet periods that create substantial fuels, followed by drought and heat, of ...
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Prairie
Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type. Temperate grassland regions include the Pampas of Argentina, Brazil and Uruguay, and the steppe of Romania, Ukraine, Russia, and Kazakhstan. Lands typically referred to as "prairie" (a French loan word) tend to be in North America. The term encompasses the lower and mid-latitude of the area referred to as the Interior Plains of Canada, the United States, and Mexico. It includes all of the Great Plains as well as the wetter, hillier land to the east. From west to east, generally the drier expanse of shortgrass prairie gives way to mixed grass prairie and ultimately the richer and wetter soils of the tallgrass prairie. In the U.S., the area is constituted by most or all of the states, from north to south, of North ...
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Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ...
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Channel (geography)
In physical geography and hydrology, a channel is a landform on which a relatively narrow body of water is situated, such as a river, river delta or strait. While ''channel'' typically refers to a natural formation, the cognate term ''canal'' denotes a similar artificial structure. Channels are important for the functionality of ports and other bodies of water used for Navigability, navigability for shipping. Naturally, channels will change their depth and capacity due to erosion and Deposition (geology), deposition processes. Humans maintain navigable channels by dredging and other engineering processes. By extension, the term also applies to fluids other than water, e.g., lava channels. The term is also traditionally used to describe the Venusian channels, waterless surface features on Venus. Formation Channel initiation refers to the site on a mountain slope where water begins to flow between identifiable banks.Bierman, R. B, David R. Montgomery (2014). Key Concepts in Geom ...
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Bedrock
In geology, bedrock is solid rock that lies under loose material ( regolith) within the crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedrock is often called an outcrop. The various kinds of broken and weathered rock material, such as soil and subsoil, that may overlie the bedrock are known as regolith. Engineering geology The surface of the bedrock beneath the soil cover (regolith) is also known as ''rockhead'' in engineering geology, and its identification by digging, drilling or geophysical methods is an important task in most civil engineering projects. Superficial deposits can be very thick, such that the bedrock lies hundreds of meters below the surface. Weathering of bedrock Exposed bedrock experiences weathering, which may be physical or chemical, and which alters the structure of the rock to leave it susceptible to erosion. Bedrock may also experience subsur ...
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Till
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is diagnostic of till. image:Glacial till exposed in roadcut-750px.jpg, Glacial till with tufts of grass Till or glacial till is unsorted glacier, glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes. Description Till is a form of '' glacial drift'', which is rock material transported by a glacier and deposited directly from the ice or from running water emerging from the ice. It is distinguished from other forms of drift in that it is de ...
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Wisconsin Glaciation
The Wisconsin glaciation, also called the Wisconsin glacial episode, was the most recent glacial period of the North American ice sheet complex, peaking more than 20,000 years ago. This advance included the Cordilleran Ice Sheet, which nucleated in the northern North American Cordillera; the Innuitian ice sheet, which extended across the Canadian Arctic Archipelago; the Greenland ice sheet; and the massive Laurentide Ice Sheet, which covered the high latitudes of central and eastern North America. This advance was synchronous with global glaciation during the last glacial period, including the North American Glacier#Classification_by_size,_shape_and_behavior, alpine glacier advance, known as the Pinedale glaciation. The Wisconsin glaciation extended from about 75,000 to 11,000 years ago, between the Sangamonian Stage and the current interglacial, the Holocene. The maximum ice extent occurred about 25,000–21,000 years ago during the last glacial maximum, also known as the ''Late W ...
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