A wetland is a distinct ecosystem, inundated by water, either permanently or seasonally, where oxygen-free processes prevail. The primary factor that distinguishes wetlands from other land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique hydric soil. Wetlands play a number of functions, including water purification, water storage, processing of carbon and other nutrients, stabilization of shorelines, support of plants and animals. Wetlands are considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life. Whether any individual wetland performs these functions, the degree to which it performs them, depends on characteristics of that wetland and the lands and waters near it. Methods for assessing these functions, wetland ecological health, general wetland condition have been developed in many regions and have contributed to wetland conservation by raising public awareness of the functions and the ecosystem services some wetlands provide.
Wetlands occur on every continent. The main wetland types are swamp, marsh and fen. Many peatlands are wetlands; the water in wetlands is either brackish, or saltwater. Wetlands can be non-tidal; the largest wetlands include the Amazon River basin, the West Siberian Plain, the Pantanal in South America, the Sundarbans in the Ganges-Brahmaputra delta. The UN Millennium Ecosystem Assessment determined that environmental degradation is more prominent within wetland systems than any other ecosystem on Earth. Constructed wetlands are used to treat municipal and industrial wastewater as well as stormwater runoff, they may play a role in water-sensitive urban design. A patch of land that develops pools of water after a rain storm would not be considered a "wetland" though the land is wet. Wetlands have unique characteristics: they are distinguished from other water bodies or landforms based on their water level and on the types of plants that live within them. Wetlands are characterized as having a water table that stands at or near the land surface for a long enough period each year to support aquatic plants.
A more concise definition is a community composed of hydric soil and hydrophytes. Wetlands have been described as ecotones, providing a transition between dry land and water bodies. Mitsch and Gosselink write that wetlands exist "...at the interface between terrestrial ecosystems and aquatic systems, making them inherently different from each other, yet dependent on both."In environmental decision-making, there are subsets of definitions that are agreed upon to make regulatory and policy decisions. A wetland is "an ecosystem that arises when inundation by water produces soils dominated by anaerobic and aerobic processes, which, in turn, forces the biota rooted plants, to adapt to flooding." There are four main kinds of wetlands – marsh, swamp and fen. Some experts recognize wet meadows and aquatic ecosystems as additional wetland types; the largest wetlands in the world include the swamp forests of the Amazon and the peatlands of Siberia. Under the Ramsar international wetland conservation treaty, wetlands are defined as follows: Article 1.1: "...wetlands are areas of marsh, peatland or water, whether natural or artificial, permanent or temporary, with water, static or flowing, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres."
Article 2.1: " may incorporate riparian and coastal zones adjacent to the wetlands, islands or bodies of marine water deeper than six metres at low tide lying within the wetlands." Although the general definition given above applies around the world, each county and region tends to have its own definition for legal purposes. In the United States, wetlands are defined as "those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, that under normal circumstances do support, a prevalence of vegetation adapted for life in saturated soil conditions. Wetlands include swamps, marshes and similar areas"; this definition has been used in the enforcement of the Clean Water Act. Some US states, such as Massachusetts and New York, have separate definitions that may differ from the federal government's. In the United States Code, the term wetland is defined "as land that has a predominance of hydric soils, is inundated or saturated by surface or groundwater at a frequency and duration sufficient to support a prevalence of hydrophytic vegetation adapted for life in saturated soil conditions and under normal circumstances supports a prevalence of such vegetation."
Related to this legal definitions, the term "normal circumstances" are conditions expected to occur during the wet portion of the growing season under normal climatic conditions, in the absence of significant disturbance. It is not uncommon for a wetland to be dry for long portions of the growing season. Wetlands can be dry during the dry season and abnormally dry periods during the wet season, but under normal environmental conditions the soils in a wetland will be saturated to the surface or inundated such that the soils become anaerobic, those conditions will persist through the wet portion of the growing season; the most important factor producing wetlands is flooding. The duration of flooding or prolonged soil saturation by groundwater determines whether the resulting wetland has aquatic, marsh or swamp vegetation
Rural Municipality of Reynolds
The Rural Municipality of Reynolds is located in southeastern Manitoba, Canada. By area, it is the largest rural municipality in Manitoba, at 3,573.3 km². Most of Manitoba's Sandilands Provincial Forest and Agassiz Provincial Forest are located here, as is part of Whiteshell Provincial Forest; the Rural Municipality of Reynolds website Manitoba Historical Society - Rural Municipality of Reynolds Map of Reynolds R. M. at Statcan
A forest is a large area dominated by trees. Hundreds of more precise definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing and ecological function. According to the used Food and Agriculture Organization definition, forests covered 4 billion hectares or 30 percent of the world's land area in 2006. Forests are the dominant terrestrial ecosystem of Earth, are distributed around the globe. Forests account for 75% of the gross primary production of the Earth's biosphere, contain 80% of the Earth's plant biomass. Net primary production is estimated at 21.9 gigatonnes carbon per year for tropical forests, 8.1 for temperate forests, 2.6 for boreal forests. Forests at different latitudes and elevations form distinctly different ecozones: boreal forests near the poles, tropical forests near the equator and temperate forests at mid-latitudes. Higher elevation areas tend to support forests similar to those at higher latitudes, amount of precipitation affects forest composition.
Human society and forests influence each other in both negative ways. Forests serve as tourist attractions. Forests can affect people's health. Human activities, including harvesting forest resources, can negatively affect forest ecosystems. Although forest is a term of common parlance, there is no universally recognised precise definition, with more than 800 definitions of forest used around the world. Although a forest is defined by the presence of trees, under many definitions an area lacking trees may still be considered a forest if it grew trees in the past, will grow trees in the future, or was designated as a forest regardless of vegetation type. There are three broad categories of forest definitions in use: administrative, land use, land cover. Administrative definitions are based upon the legal designations of land, bear little relationship to the vegetation growing on the land: land, designated as a forest is defined as a forest if no trees are growing on it. Land use definitions are based upon the primary purpose.
For example, a forest may be defined as any land, used for production of timber. Under such a land use definition, cleared roads or infrastructure within an area used for forestry, or areas within the region that have been cleared by harvesting, disease or fire are still considered forests if they contain no trees. Land cover definitions define forests based upon the type and density of vegetation growing on the land; such definitions define a forest as an area growing trees above some threshold. These thresholds are the number of trees per area, the area of ground under the tree canopy or the section of land, occupied by the cross-section of tree trunks. Under such land cover definitions, an area of land can only be known as forest if it is growing trees. Areas that fail to meet the land cover definition may be still included under while immature trees are establishing if they are expected to meet the definition at maturity. Under land use definitions, there is considerable variation on where the cutoff points are between a forest and savanna.
Under some definitions, forests require high levels of tree canopy cover, from 60% to 100%, excluding savannas and woodlands in which trees have a lower canopy cover. Other definitions consider savannas to be a type of forest, include all areas with tree canopies over 10%; some areas covered in trees are defined as agricultural areas, e.g. Norway spruce plantations in Austrian forest law when the trees are being grown as Christmas trees and below a certain height; the word forest comes from Middle English, from Old French forest "forest, vast expanse covered by trees". A borrowing of the Medieval Latin word foresta "open wood", foresta was first used by Carolingian scribes in the Capitularies of Charlemagne to refer to the king's royal hunting grounds; the term was not endemic to Romance languages. The exact origin of Medieval Latin foresta is obscure; some authorities claim the word derives from the Late Latin phrase forestam silvam, meaning "the outer wood". Frankish *forhist is attested by Old High German forst "forest", Middle Low German vorst "forest", Old English fyrhþ "forest, game preserve, hunting ground", Old Norse fýri "coniferous forest", all of which derive from Proto-Germanic *furhísa-, *furhíþija- "a fir-wood, coniferous forest", from Proto-Indo-European *perkwu- "a coniferous or mountain forest, wooded height".
Uses of the word "forest" in English to denote any uninhabited area of non-enclosure are now considered archaic. The word was introduced by the Norman rulers of England as a legal term denoting an uncultivated area set aside for hunting by feudal nobility; these hunting forests were not neces
In geology, a boulder is a rock fragment with size greater than 25.6 centimetres in diameter. Smaller pieces are called pebbles. While a boulder may be small enough to move or roll manually, others are massive. In common usage, a boulder is too large for a person to move. Smaller boulders are just called rocks or stones; the word boulder is short for boulder stone, from Swedish bullersten. In places covered by ice sheets during Ice Ages, such as Scandinavia, northern North America, Siberia, glacial erratics are common. Erratics are boulders picked up by ice sheets during their advance, deposited when they melt, they are called "erratic" because they are of a different rock type than the bedrock on which they are deposited. One of them is used as the pedestal of the Bronze Horseman in Russia; some noted rock formations involve giant boulders exposed by erosion, such as the Devil's Marbles in Australia's Northern Territory, the Horeke basalts in New Zealand, where an entire valley contains only boulders, The Baths on the island of Virgin Gorda in the British Virgin Islands.
Boulder-sized clasts are found in some sedimentary rocks, such as coarse conglomerate and boulder clay. The climbing of large boulders is called bouldering. Road debris Monolith Peñón de Ponce Media related to Boulders at Wikimedia Commons
An esker, eschar, or os, sometimes called an asar, osar, or serpent kame, is a long, winding ridge of stratified sand and gravel, examples of which occur in glaciated and glaciated regions of Europe and North America. Eskers are several kilometres long and, because of their peculiar uniform shape, are somewhat like railway embankments; the term esker is derived from the Irish word eiscir, which means "ridge or elevation one separating two plains or depressed surfaces". The Irish word was and is used to describe long sinuous ridges, which are now known to be deposits of fluvio-glacial material; the best-known example of such an eiscir is the Eiscir Riada, which runs nearly the whole width of Ireland from Dublin to Galway, a distance of 200 km, is still followed by the main Dublin-Galway road The synonym os comes from the Swedish word for an esker, ås. Most eskers are argued to have formed within ice-walled tunnels by streams which flowed within and under glaciers, they tended to form around the time of the glacial maximum when the glacier was sluggish.
After the retaining ice walls melted away, stream deposits remained as long winding ridges. Water can flow uphill. Eskers may form above glaciers by accumulation of sediment in supraglacial channels, in crevasses, in linear zones between stagnant blocks, or in narrow embayments at glacier margins. Eskers form near the terminal zone of glaciers, where the ice is not moving as fast and is thin. Plastic flow and melting of the basal ice determines the shape of the subglacial tunnel; this in turn determines the shape and structure of an esker. Eskers may be part of a branching system with tributary eskers, they are not found as continuous ridges, but have gaps that separate the winding segments. The ridge crests of eskers are not level for long, are knobby. Eskers may be sharp-crested with steep sides, they can reach hundreds of kilometers in length and are 20–30 metres in height. The path of an esker is governed by its water pressure in relation to the overlying ice; the pressure of the ice was at such a point that it would allow eskers to run in the direction of glacial flow, but force them into the lowest possible points such as valleys or river beds, which may deviate from the direct path of the glacier.
This process is what produces the wide eskers upon which highways can be built. Less pressure, occurring in areas closer to the glacial maximum, can cause ice to melt over the stream flow and create steep-walled, sharply-arched tunnels; the concentration of rock debris in the ice and the rate at which sediment is delivered to the tunnel by melting and from upstream transport determines the amount of sediment in an esker. The sediment consists of coarse-grained, water-laid sand and gravel, although gravelly loam may be found where the rock debris is rich in clay; this sediment is stratified and sorted, consists of pebble/cobble-sized material with occasional boulders. Bedding may be irregular but is always present, cross-bedding is common. Eskers are critical to the ecology of Northern Canada. Several plants that grow on eskers, including bear root and cranberries, are important food for bears and migrating waterfowl. In Sweden Uppsalaåsen passes through Uppsala city; the Badelundaåsen esker runs for over 300 km from Nyköping to lake Siljan.
Great Esker Park runs along the Back River in Weymouth, Massachusetts and is home to the highest esker in North America. Pispala in Tampere, Finland is on an esker between two lakes carved by glaciers. A similar site is Punkaharju in Finnish Lakeland; the village of Kemnay in Aberdeenshire, Scotland has a 5 km esker locally called the Kemb Hills. There are over 1,000 eskers in the state of Michigan in the south-central Lower Peninsula; the longest esker in Michigan is the 22 mile long Mason Esker, which stretches south-southeast from DeWitt through Lansing and Holt, before ending near Mason. Esker systems in the U. S. state of Maine can be traced for up to 100 miles. The Thelon Esker runs for 800 kilometers and straddles the border between Northwest Territories and Nunavut in Canada. Ovayok or Mount Pelly in Ovayok Territorial Park, Nunavut in Canada. Roads are sometimes built along eskers to save expense. Examples include the Denali Highway in Alaska, the Trans-Taiga Road in Quebec, the "Airline" segment of Maine State Route 9 between Bangor and Calais.
There are numerous long eskers in the Adirondack State Park in upstate New York. Tunnel valley – A U-shaped valley cut by water under the glacial ice near the margin of continental ice sheets Glacial landform – Landform created by the action of glaciers Glacier morphology Eskers Provincial Park Trenhaile, Alan. Geomorphology: A Canadian Perspective. Don Mills, Ontario: Oxford University Press. Pp. 188–191. ISBN 0-19-542474-3. Oblique aerial photo of an esker in Waterford, Maine Esker Riada Webpage Diagram illustrating tunnel in glacier before retreat of ice, forming meandering esker in The Ice Melts: Deposition on page 6 of "Pennsylvania and the Ice Age" published 1999 by PA DCNR Bureau of Topographic and Geologic Survey The Bridgenorth Esker: geomorphology and sedimentology
A glacier is a persistent body of dense ice, moving under its own weight. Glaciers deform and flow due to stresses induced by their weight, creating crevasses and other distinguishing features, they abrade rock and debris from their substrate to create landforms such as cirques and moraines. Glaciers form only on land and are distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets in the polar regions, but glaciers may be found in mountain ranges on every continent including Oceania's high-latitude oceanic island countries such as New Zealand and Papua New Guinea. Between 35°N and 35°S, glaciers occur only in the Himalayas, Rocky Mountains, a few high mountains in East Africa, New Guinea and on Zard Kuh in Iran. Glaciers cover about 10 percent of Earth's land surface. Continental glaciers cover nearly 13 million km2 or about 98 percent of Antarctica's 13.2 million km2, with an average thickness of 2,100 m.
Greenland and Patagonia have huge expanses of continental glaciers. Glacial ice is the largest reservoir of fresh water on Earth. Many glaciers from temperate and seasonal polar climates store water as ice during the colder seasons and release it in the form of meltwater as warmer summer temperatures cause the glacier to melt, creating a water source, important for plants and human uses when other sources may be scant. Within high-altitude and Antarctic environments, the seasonal temperature difference is not sufficient to release meltwater. Since glacial mass is affected by long-term climatic changes, e.g. precipitation, mean temperature, cloud cover, glacial mass changes are considered among the most sensitive indicators of climate change and are a major source of variations in sea level. A large piece of compressed ice, or a glacier, appears blue, as large quantities of water appear blue; this is. The other reason for the blue color of glaciers is the lack of air bubbles. Air bubbles, which give a white color to ice, are squeezed out by pressure increasing the density of the created ice.
The word glacier is a loanword from French and goes back, via Franco-Provençal, to the Vulgar Latin glaciārium, derived from the Late Latin glacia, Latin glaciēs, meaning "ice". The processes and features caused by or related to glaciers are referred to as glacial; the process of glacier establishment and flow is called glaciation. The corresponding area of study is called glaciology. Glaciers are important components of the global cryosphere. Glaciers are categorized by their morphology, thermal characteristics, behavior. Cirque glaciers form on the slopes of mountains. A glacier that fills a valley is called a valley glacier, or alternatively an alpine glacier or mountain glacier. A large body of glacial ice astride a mountain, mountain range, or volcano is termed an ice cap or ice field. Ice caps have an area less than 50,000 km2 by definition. Glacial bodies larger than 50,000 km2 are called continental glaciers. Several kilometers deep, they obscure the underlying topography. Only nunataks protrude from their surfaces.
The only extant ice sheets are the two that cover most of Greenland. They contain vast quantities of fresh water, enough that if both melted, global sea levels would rise by over 70 m. Portions of an ice sheet or cap that extend into water are called ice shelves. Narrow, fast-moving sections of an ice sheet are called ice streams. In Antarctica, many ice streams drain into large ice shelves; some drain directly into the sea with an ice tongue, like Mertz Glacier. Tidewater glaciers are glaciers that terminate in the sea, including most glaciers flowing from Greenland, Antarctica and Ellesmere Islands in Canada, Southeast Alaska, the Northern and Southern Patagonian Ice Fields; as the ice reaches the sea, pieces break off, or calve. Most tidewater glaciers calve above sea level, which results in a tremendous impact as the iceberg strikes the water. Tidewater glaciers undergo centuries-long cycles of advance and retreat that are much less affected by the climate change than those of other glaciers.
Thermally, a temperate glacier is at melting point throughout the year, from its surface to its base. The ice of a polar glacier is always below the freezing point from the surface to its base, although the surface snowpack may experience seasonal melting. A sub-polar glacier includes both temperate and polar ice, depending on depth beneath the surface and position along the length of the glacier. In a similar way, the thermal regime of a glacier is described by its basal temperature. A cold-based glacier is below freezing at the ice-ground interface, is thus frozen to the underlying substrate. A warm-based glacier is above or at freezing at the interface, is able to slide at this contact; this contrast is thought to a large extent to govern the ability of a glacier to erode its bed, as sliding ice promotes plucking at rock from the surface below. Glaciers which are cold-based and warm-based are known as polythermal. Glaciers form where the accumulation of ice exceeds ablation. A glacier originates from a landform called'cirque' – a armchair-shaped geological feature (such as a depressio
Canada is a country in the northern part of North America. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering 9.98 million square kilometres, making it the world's second-largest country by total area. Canada's southern border with the United States is the world's longest bi-national land border, its capital is Ottawa, its three largest metropolitan areas are Toronto and Vancouver. As a whole, Canada is sparsely populated, the majority of its land area being dominated by forest and tundra, its population is urbanized, with over 80 percent of its inhabitants concentrated in large and medium-sized cities, many near the southern border. Canada's climate varies across its vast area, ranging from arctic weather in the north, to hot summers in the southern regions, with four distinct seasons. Various indigenous peoples have inhabited what is now Canada for thousands of years prior to European colonization. Beginning in the 16th century and French expeditions explored, settled, along the Atlantic coast.
As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces; this began an accretion of provinces and territories and a process of increasing autonomy from the United Kingdom. This widening autonomy was highlighted by the Statute of Westminster of 1931 and culminated in the Canada Act of 1982, which severed the vestiges of legal dependence on the British parliament. Canada is a parliamentary democracy and a constitutional monarchy in the Westminster tradition, with Elizabeth II as its queen and a prime minister who serves as the chair of the federal cabinet and head of government; the country is a realm within the Commonwealth of Nations, a member of the Francophonie and bilingual at the federal level. It ranks among the highest in international measurements of government transparency, civil liberties, quality of life, economic freedom, education.
It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many other countries. Canada's long and complex relationship with the United States has had a significant impact on its economy and culture. A developed country, Canada has the sixteenth-highest nominal per capita income globally as well as the twelfth-highest ranking in the Human Development Index, its advanced economy is the tenth-largest in the world, relying chiefly upon its abundant natural resources and well-developed international trade networks. Canada is part of several major international and intergovernmental institutions or groupings including the United Nations, the North Atlantic Treaty Organization, the G7, the Group of Ten, the G20, the North American Free Trade Agreement and the Asia-Pacific Economic Cooperation forum. While a variety of theories have been postulated for the etymological origins of Canada, the name is now accepted as coming from the St. Lawrence Iroquoian word kanata, meaning "village" or "settlement".
In 1535, indigenous inhabitants of the present-day Quebec City region used the word to direct French explorer Jacques Cartier to the village of Stadacona. Cartier used the word Canada to refer not only to that particular village but to the entire area subject to Donnacona. From the 16th to the early 18th century "Canada" referred to the part of New France that lay along the Saint Lawrence River. In 1791, the area became two British colonies called Upper Canada and Lower Canada collectively named the Canadas. Upon Confederation in 1867, Canada was adopted as the legal name for the new country at the London Conference, the word Dominion was conferred as the country's title. By the 1950s, the term Dominion of Canada was no longer used by the United Kingdom, which considered Canada a "Realm of the Commonwealth"; the government of Louis St. Laurent ended the practice of using'Dominion' in the Statutes of Canada in 1951. In 1982, the passage of the Canada Act, bringing the Constitution of Canada under Canadian control, referred only to Canada, that year the name of the national holiday was changed from Dominion Day to Canada Day.
The term Dominion was used to distinguish the federal government from the provinces, though after the Second World War the term federal had replaced dominion. Indigenous peoples in present-day Canada include the First Nations, Métis, the last being a mixed-blood people who originated in the mid-17th century when First Nations and Inuit people married European settlers; the term "Aboriginal" as a collective noun is a specific term of art used in some legal documents, including the Constitution Act 1982. The first inhabitants of North America are hypothesized to have migrated from Siberia by way of the Bering land bridge and arrived at least 14,000 years ago; the Paleo-Indian archeological sites at Old Crow Flats and Bluefish Caves are two of the oldest sites of human habitation in Canada. The characteristics of Canadian indigenous societies included permanent settlements, complex societal hierarchies, trading networks; some of these cultures had collapsed by the time European explorers arrived in the late 15th and early 16th centuries and have only been discovered through archeological investigations.
The indigenous population at the time of the first European settlements is estimated to have been between 200,000