A mound is a heaped pile of earth, sand, rocks, or debris. Most mounds are earthen formations such as hills and mountains if they appear artificial. A mound may be any rounded area of topographically higher elevation on any surface. Artificial mounds have been created for a variety of reasons throughout history, including ceremonial and commemorative purposes. In the archaeology of the United States and Canada, a mound is a deliberately constructed elevated earthen structure or earthwork, intended for a range of potential uses. In European and Asian archaeology, the word "tumulus" may be used as a synonym for an artificial hill if the hill is related to particular burial customs. While the term "mound" may be applied to historic constructions, most mounds in the United States are pre-Columbian earthworks, built by Native American peoples. Native Americans built a variety of mounds, including flat-topped pyramids or cones known as platform mounds, rounded cones, ridge or loaf-shaped mounds; some mounds took such as the outline of cosmologically significant animals.
These are known as effigy mounds. Some mounds, such as a few in Wisconsin, have rock formations, or petroforms within them, on them, or near them. While these mounds are not as famous as burial mounds, like their European analogs, Native American mounds have a variety of other uses. While some prehistoric cultures, like the Adena culture, used mounds preferentially for burial, others used mounds for other ritual and sacred acts, as well as for secular functions; the platform mounds of the Mississippian culture, for example, may have supported temples, the houses of chiefs, council houses, may have acted as a platform for public speaking. Other mounds would have been part of defensive walls to protect a certain area; the Hopewell culture used mounds as markers of complex astronomical alignments related to ceremonies. Mounds and related earthworks are the only significant monumental construction in pre-Columbian Eastern and Central North America. Mounds are given different names depending on, they can be located all across the world in spots such as Asia and the Americas.
"Mound builders" have more been associated with the mounds in the Americas. They all have different meanings and sometimes are constructed as animals and can be seen from aerial views. Kankali Tila is a famous mound located at Mathura in the Indian state of Uttar Pradesh. A Jain stupa was excavated here in 1890-91 by Dr. Fuhrer. Mound, as a technical term in archaeology, is not in favor in the rest of the world. More specific local terminology is preferred, each of these terms has its own article. Cairn Chambered cairn Effigy mound Kofun Platform mound Subglacial mound Tell Tumulus Bank barrow Bell barrow Bowl barrow Chambered long barrow Kurgan Long barrow Oval barrow List of burial mounds in the United States Fort Ancient Kofun period Kurgan hypothesis Mississippian Period Neolithic Europe Olmec La Venta San Jose Mogote Petroform Pyramid Prehistoric Britain Stupa Woodland Period Crystal River Archaeological State Park ZigguratAnimalsMound-building termites The dictionary definition of mound at Wiktionary "Mound".
Encyclopædia Britannica. 18. 1911
A hill is a landform that extends above the surrounding terrain. It has a distinct summit, although in areas with scarp/dip topography a hill may refer to a particular section of flat terrain without a massive summit; the distinction between a hill and a mountain is unclear and subjective, but a hill is universally considered to be less tall and less steep than a mountain. In the United Kingdom, geographers regarded mountains as hills greater than 1,000 feet above sea level, which formed the basis of the plot of the 1995 film The Englishman Who Went Up a Hill But Came Down a Mountain. In contrast, hillwalkers have tended to regard mountains as peaks 2,000 feet above sea level: the Oxford English Dictionary suggests a limit of 2,000 feet and Whittow states "Some authorities regard eminences above 600 m as mountains, those below being referred to as hills." Today, a mountain is defined in the UK and Ireland as any summit at least 2,000 feet or 610 meters high, while the official UK government's definition of a mountain is a summit of 600 meters or higher.
Some definitions include a topographical prominence requirement 100 feet or 500 feet. In practice, mountains in Scotland are referred to as "hills" no matter what their height, as reflected in names such as the Cuillin Hills and the Torridon Hills. In Wales, the distinction is more a term of land use and appearance and has nothing to do with height. For a while, the U. S. defined a mountain as being more tall. Any similar landform lower; the United States Geological Survey, has concluded that these terms do not in fact have technical definitions in the U. S; the Great Soviet Encyclopedia defined "hill" as an upland with a relative height up to 200 m. A hillock is a small hill. Other words include its variant, knowe. Artificial hills may be referred to including mound and tumulus. Hills may form through geomorphic phenomena: faulting, erosion of larger landforms such as mountains, movement and deposition of sediment by glaciers The rounded peaks of hills results from the diffusive movement of soil and regolith covering the hill, a process known as downhill creep.
Various names used to describe types of hill, based on method of formation. Many such names originated in one geographical region to describe a type of hill formation peculiar to that region, though the names are adopted by geologists and used in a wider geographical context; these include: Brae -- Scottish term for a brow of a hill. Drumlin – an elongated whale-shaped hill formed by glacial action. Butte – an isolated hill with steep sides and a small flat top, formed by weathering. Kuppe – a rounded hill or low mountain, typical of central Europe Tor – a rock formation found on a hilltop. Puy – used in the Auvergne, France, to describe a conical volcanic hill. Pingo – a mound of earth-covered ice found in the Arctic and Antarctica. Many settlements were built on hills, either to avoid floods, or for defense, or to avoid densely forested areas. For example, Ancient Rome was built on seven hills; some settlements in the Middle East, are located on artificial hills consisting of debris that has accumulated over many generations.
Such a location is known as a "tell". In northern Europe, many ancient monuments are sited in heaps; some of these are defensive structures. In Britain, many churches at the tops of hills are thought to have been built on the sites of earlier pagan holy places; the National Cathedral in Washington, DC has followed this tradition and was built on the highest hill in that city. Hills provide a major advantage to an army, giving them an elevated firing position and forcing an opposing army to charge uphill to attack them, they may conceal forces behind them, allowing a force to lie in wait on the crest of a hill, using that crest for cover, firing on unsuspecting attackers as they broach the hilltop. As a result, conventional military strategies demand possession of high ground. Hills have been the sites of many noted battles, such as the first recorded military conflict in Scotland known as the battle of Mons Graupius. Modern conflicts include the Battle of Bunker Hill in the American War of Independence and Cemetery Hill and Culp's Hill in the Battle of Gettysburg, the turning point of the American Civil War.
The Battle of San Juan Hill in the Spanish–American War won Americans control of Santiago. The Battle of Alesia was fought from a hilltop fort. Fighting on Mamayev Kurgan during the Battle of Stalingrad and the Umurbrogol Pocket in the Battle of Peleliu were examples of bloody fighting for high ground. Another recent example is the Kargil War between Pakistan; the Great Wall of China is an example of an advantage provider. It is built on mountain tops, was meant to defend against invaders from the north, among others, Mongolians. Hillwalking is a British English term for a form of hiking; the activity is distinguished from mountaineering as it does no
An island or isle is any piece of sub-continental land, surrounded by water. Small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or a lake island may be called an eyot or ait, a small island off the coast may be called a holm. A grouping of geographically or geologically related islands is called an archipelago, such as the Philippines. An island may be described despite the presence of an artificial land bridge; some places may retain "island" in their names for historical reasons after being connected to a larger landmass by a land bridge or landfill, such as Coney Island and Coronado Island, though these are speaking, tied islands. Conversely, when a piece of land is separated from the mainland by a man-made canal, for example the Peloponnese by the Corinth Canal or Marble Hill in northern Manhattan during the time between the building of the United States Ship Canal and the filling-in of the Harlem River which surrounded the area, it is not considered an island.
There are two main types of islands in the sea: oceanic. There are artificial islands; the word island derives from Middle English iland, from Old English igland. However, the spelling of the word was modified in the 15th century because of a false etymology caused by an incorrect association with the etymologically unrelated Old French loanword isle, which itself comes from the Latin word insula. Old English ieg is a cognate of Swedish ö and German Aue, related to Latin aqua. Greenland is the world's largest island, with an area of over 2.1 million km2, while Australia, the world's smallest continent, has an area of 7.6 million km2, but there is no standard of size that distinguishes islands from continents, or from islets. There is a difference between continents in terms of geology. Continents are the largest landmass of a particular continental plate. By contrast, islands are either extensions of the oceanic crust, or belong to a continental plate containing a larger landmass. Continental islands are bodies of land.
Examples are Borneo, Sumatra, Sakhalin and Hainan off Asia. A special type of continental island is the microcontinental island, created when a continent is rifted. Examples are Madagascar and Socotra off Africa, New Caledonia, New Zealand, some of the Seychelles. Another subtype is an island or bar formed by deposition of tiny rocks where water current loses some of its carrying capacity; this includes: barrier islands, which are accumulations of sand deposited by sea currents on the continental shelves fluvial or alluvial islands formed in river deltas or midstream within large rivers. While some are transitory and may disappear if the volume or speed of the current changes, others are stable and long-lived. Islets are small islands. Oceanic islands are islands; the vast majority are volcanic in origin, such as Saint Helena in the South Atlantic Ocean. The few oceanic islands that are not volcanic are tectonic in origin and arise where plate movements have lifted up the ocean floor above the surface.
Examples are Saint Paul Rocks in the Atlantic Ocean and Macquarie Island in the Pacific. One type of volcanic oceanic island is found in a volcanic island arc; these islands arise from volcanoes. Examples are the Aleutian Islands, the Mariana Islands, most of Tonga in the Pacific Ocean; the only examples in the Atlantic Ocean are some of the Lesser Antilles and the South Sandwich Islands. Another type of volcanic oceanic island occurs. There are two examples: Iceland, the world's second largest volcanic island, Jan Mayen. Both are in the Atlantic. A third type of volcanic oceanic island is formed over volcanic hotspots. A hotspot is more or less stationary relative to the moving tectonic plate above it, so a chain of islands results as the plate drifts. Over long periods of time, this type of island is "drowned" by isostatic adjustment and eroded, becoming a seamount. Plate movement across a hot-spot produces a line of islands oriented in the direction of the plate movement. An example is the Hawaiian Islands, from Hawaii to Kure, which continue beneath the sea surface in a more northerly direction as the Emperor Seamounts.
Another chain with similar orientation is the Tuamotu Archipelago. The southernmost chain is the Austral Islands, with its northerly trending part the atolls in the nation of Tuvalu. Tristan da Cunha is an example of a hotspot volcano in the Atlantic Ocean. Another hotspot in the Atlantic is the island of Surtsey, formed in 1963. An atoll is an island formed from a coral reef that has grown on an eroded and submerged volcanic island; the reef forms a new island. Atolls are ring-shaped with a central lagoon. Examples are the Line Islands
Population density is a measurement of population per unit area or unit volume. It is applied to living organisms, most of the time to humans, it is a key geographical term. In simple terms population density refers to the number of people living in an area per kilometer square. Population density is population divided by total land water volume, as appropriate. Low densities may lead to further reduced fertility; this is called the Allee effect after the scientist. Examples of the causes in low population densities include: Increased problems with locating sexual mates Increased inbreeding For humans, population density is the number of people per unit of area quoted per square kilometer or square mile; this may be calculated for a county, country, another territory or the entire world. The world's population is around 7,500,000,000 and Earth's total area is 510,000,000 square kilometers. Therefore, the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2. If only the Earth's land area of 150,000,000 km2 is taken into account human population density is 50 per km2.
This includes all continental and island land area, including Antarctica. If Antarctica is excluded population density rises to over 55 people per km2. However, over half of the Earth's land mass consists of areas inhospitable to human habitation, such as deserts and high mountains, population tends to cluster around seaports and fresh-water sources. Thus, this number by itself does not give any helpful measurement of human population density. Several of the most densely populated territories in the world are city-states and dependencies; these territories have a small area and a high urbanization level, with an economically specialized city population drawing on rural resources outside the area, illustrating the difference between high population density and overpopulation The potential to maintain the agricultural aspects of deserts is limited as there is not enough precipitation to support a sustainable land. The population in these areas are low. Therefore, cities in the Middle East, such as Dubai, have been increasing in population and infrastructure growth at a fast pace.
Cities with high population densities are, by some, considered to be overpopulated, though this will depend on factors like quality of housing and infrastructure and access to resources. Most of the most densely populated cities are in Southeast Asia, though Cairo and Lagos in Africa fall into this category. City population and area are, however dependent on the definition of "urban area" used: densities are invariably higher for the central city area than when suburban settlements and the intervening rural areas are included, as in the areas of agglomeration or metropolitan area, the latter sometimes including neighboring cities. For instance, Milwaukee has a greater population density when just the inner city is measured, the surrounding suburbs excluded. In comparison, based on a world population of seven billion, the world's inhabitants, as a loose crowd taking up ten square feet per person, would occupy a space a little larger than Delaware's land area; the Gaza Strip has a population density of 5,046 pop/km.
Although arithmetic density is the most common way of measuring population density, several other methods have been developed to provide a more accurate measure of population density over a specific area. Arithmetic density: The total number of people / area of land Physiological density: The total population / area of arable land Agricultural density: The total rural population / area of arable land Residential density: The number of people living in an urban area / area of residential land Urban density: The number of people inhabiting an urban area / total area of urban land Ecological optimum: The density of population that can be supported by the natural resources Demography Human geography Idealized population Optimum population Population genetics Population health Population momentum Population pyramid Rural transport problem Small population size Distance sampling List of population concern organizations List of countries by population density List of cities by population density List of city districts by population density List of English districts by population density List of European cities proper by population density List of United States cities by population density List of islands by population density List of U.
S. states by population density List of Australian suburbs by population density Selected Current and Historic City, Ward & Neighborhood Density Duncan Smith / UCL Centre for Advanced Spatial Analysis. "World Population Density". Exploratory map shows data from the Global Human Settlement Layer produced by the European Commission JRC and the CIESIN Columbia University
Tjøtta is a village in Alstahaug Municipality in Nordland county, Norway. It is located on the southern tip of the island of Tjøtta, located south of the large island of Alsta; the village is located on an island, but it does have a mainland road connection via Norwegian County Road 17 and a series of bridges heading north to the town of Sandnessjøen. The historic Tjøtta Church is located in the village; the 0.33-square-kilometre village has a population of 214 which gives the village a population density of 648 inhabitants per square kilometre. The climate is mild, compared with most of Northern Norway, with a long summer suited for agriculture; the monthly 24-hr averages range from − 1.8 °C in the coldest month to 13 °C in both August. The average yearly rainfall is 1,020 millimetres. Tjøtta is mentioned in the Heimskringla many times. There is archeological evidence of Iron Age agriculture in the area- Tjøtta gard, the largest medieval farm in North Norway, is located in Tjøtta. From 1862 until 1965, the village of Tjøtta was the administrative centre of the old municipality of Tjøtta.