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Glacial Refugium
A glacial refugium (plural glacial refugia) is a geographic region which made possible the survival of flora and fauna during ice ages and allowed for post-glacial re-colonization. Different types of glacial refugia can be distinguished, namely nunatak, peripheral, and lowland.Holderegger, R., Thiel-Egenter, C. (2009): A discussion of different types of glacial refugia used in mountain biogeography and phytogeography. Journal of Biogeography 36, 476-480. Glacial refugia have been suggested as a major cause of floral and faunal distribution patterns in both temperate and tropical latitudes. With respect to disjunct populations of modern-day species, especially in birds, doubt has been cast on the validity of such inferences, as much of the differentiation between populations observed today may have occurred before or after their restriction to refugia. In contrast, isolated geographic locales that host one or more critically endangered species (regarded as paleoendemics or glacial r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flora
Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. The corresponding term for animals is ''fauna'', and for fungi, it is ''funga''. Sometimes bacteria and fungi are also referred to as flora as in the terms ''gut flora'' or ''skin flora'' for purposes of specificity. Etymology The word "flora" comes from the Latin name of Flora (mythology), Flora, the goddess of plants, flowers, and fertility in Roman mythology. The technical term "flora" is then derived from a metonymy of this goddess at the end of the sixteenth century. It was first used in poetry to denote the natural vegetation of an area, but soon also assumed the meaning of a work cataloguing such vegetation. Moreover, "Flora" was used to refer to the flowers of an artificial garden in the seventeenth century. The distinction between vegetation (the general appearance of a community) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peak Glacial Refuges Eastern North America
Peak or The Peak may refer to: Basic meanings Geology * Mountain peak ** Pyramidal peak, a mountaintop that has been sculpted by erosion to form a point Mathematics * Peak hour or rush hour, in traffic congestion * Peak (geometry), an (''n''-3)-dimensional element of a polytope * Peak electricity demand or peak usage * Peak-to-peak, the highest (or sometimes the highest and lowest) points on a varying waveform * Peak (pharmacology), the time at which a drug reaches its maximum plasma concentration * Peak experience, psychological term for a euphoric mental state Resource production In terms of resource production, the peak is the moment when the production of a resource reaches a maximum level, after which it declines; in particular see: * Peak oil * Peak car * Peak coal * Peak farmland * Peak gas * Peak minerals * Peak water * Peak wheat * Peak wood Other basic meanings * Visor, a part of a hat, known as a "peak" in British English * Peaked cap Geography * Peak District in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refugium (population Biology)
In biology, a refugium (plural: ''refugia'') is a location which supports an isolated or relict population of a once more widespread species. This isolation ( allopatry) can be due to climatic changes, geography, or human activities such as deforestation and overhunting. Present examples of refugial animal species are the mountain gorilla, isolated to specific mountains in central Africa, and the Australian sea lion, isolated to specific breeding beaches along the south-west coast of Australia, due to humans taking so many of their number as game. This resulting isolation, in many cases, can be seen as only a temporary state; however, some refugia may be longstanding, thereby having many endemic species, not found elsewhere, which survive as relict populations. The Indo-Pacific Warm Pool has been proposed to be a longstanding refugium, based on the discovery of the "living fossil" of a marine dinoflagellate called '' Dapsilidinium pastielsii'', currently found only in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Last Glacial Maximum Refugia
Last Glacial Maximum refugia were places ('' refugia'') in which humans and other species survived during the Last Glacial Period, around 25,000 to 18,000 years ago. Glacial refugia are areas that climate changes were not as severe, and where species could recolonize after deglaciation. Globally, the temperatures during the Last Glacial Maximum (LGM) were 4.0 ± 0.8 °C cooler than present day. The colder climate contributed to ice sheet growth in North America, Europe, and Antarctica. At this time there were further major climate shifts around the world. Some areas became too dry to support much life; others housed more vegetation and animals. The northern hemisphere was heavily impacted by ice sheets during the LGM. Some recent archaeological evidence suggests the possibility that human arrival in the Americas may have occurred prior to the Last Glacial Maximum more than 30,000 years ago. This evidence was found adjacent to ice sheets, but research is still in an early s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drought Refuge
A drought refuge is a site that provides permanent fresh water or moist conditions for plants and animals, acting as a refuge habitat when surrounding areas are affected by drought and allowing ecosystems and core species populations to survive until the drought breaks. Drought refuges are important for conserving ecosystems in places where the effects of climatic variability are exacerbated by human activities. Description Reliable drought refuges are characterised by the ability to retain sufficient water throughout the drought, having water quality good enough to maintain the life of the ecosystem that are not subject to physical disturbance and that have access to surrounding habitat, so that refugees can recolonise the main habitat when the drought ends. For fish and aquatic invertebrates a drought refuge may be an isolated permanent pool in a stream that ceases to flow and mostly dries up during a period of drought.Bond, N.R. (2007). ''Identifying, mapping and managing d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chattahoochee River
The Chattahoochee River () is a river in the Southeastern United States, Southeastern United States. It forms the southern half of the Alabama and Georgia (U.S. state), Georgia border, as well as a portion of the Florida and Georgia border. It is a tributary of the Apalachicola River, a relatively short river formed by the confluence of the Chattahoochee and Flint River (Georgia), Flint rivers and emptying from Florida into Apalachicola Bay in the Gulf of Mexico. The Chattahoochee River is about long. The Chattahoochee, Flint, and Apalachicola rivers together make up the Apalachicola–Chattahoochee–Flint River Basin (ACF River Basin). The Chattahoochee makes up the largest part of the ACF's drainage basin. Course The River source, source of the Chattahoochee River is located in Jacks Gap at the southeastern foot of Jacks Knob, in the very southeastern corner of Union County, Georgia, Union County, in the southern Blue Ridge Mountains, a subrange of the Appalachian Mountai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxus Floridana
''Taxus floridana'', the Florida yew, is a species of yew, endemic to a small area of the Apalachicola River. This species has a restricted extent of occurrence (EOO) of 24km along the Apalachicola River and resides in the mesophytic forests of northern Florida at altitudes of 15–40 m. It is listed as critically endangeredFlora of North America''Taxus floridana''/ref> and is protected in reserves at the Torreya State Park and at the Nature Conservancy's Apalachicola Bluffs and Ravines Preserve. The Florida yew has legal protection under the United States and Florida Endangered Species laws. This species is considered endangered because of how rare it is and its limited range. Description It is an evergreen coniferous shrub or small tree growing to 6 m (rarely 10 m) tall, with a trunk up to 38 cm diameter. The bark is thin, scaly purple-brown, and the branches are irregularly orientated. The shoots are green at first, becoming brown after three or four years. The le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torreya Taxifolia
''Torreya taxifolia'', commonly known as Florida torreya or stinking-cedar, but also sometimes as Florida nutmeg or gopher wood, is an endangered canopy (biology), subcanopy tree of the yew Family (biology), family, Taxaceae. It is native to only a small glacial refugium in the southeastern United States, at the state border region of northern Florida and southwestern Georgia (U.S. state), Georgia. Species discovery In 1821, colonial control of Spanish Florida shifted from Spain to the United States through the Adams–Onís Treaty, Adams-Onis Treaty. American settlers, including plantation owners and their slaves, began to move into the Florida Territory, exacerbating the Seminole Wars, on-going conflict with the refugee Red Sticks, Red Stick Creek and their allies from the Creek War and the emigrant population of Seminole, Seminoles and Maroons. One such plantation owner was the patriarch of the Croom family, who in 1826 purchased land around the town of Tallahassee. When he d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altamaha River
The Altamaha River is a major river in the U.S. state of Georgia (U.S. state), Georgia. It flows generally eastward for from its Source (river or stream), origin at the confluence of the Oconee River and Ocmulgee River towards the Atlantic Ocean, where it empties into the ocean near Brunswick, Georgia. No dams are directly on the Altamaha, though some are on the Oconee and the Ocmulgee. Including its tributaries, the Altamaha River's drainage basin is about in size, qualifying it among the larger river basins of the US Atlantic coast.The Altamaha River Course The Altamaha River originates at the confluence of the Oconee and Ocmulgee Rivers, near Lumber City, Georgia, Lumber City. At its source, the river forms the border between Jeff Davis County, Georgia, Jeff Davis ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippi River
The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Itasca in northern Minnesota, it flows generally south for to the Mississippi River Delta in the Gulf of Mexico. With its many tributaries, the Mississippi's Drainage basin, watershed drains all or parts of 32 U.S. states and two Canadian provinces between the Rocky Mountains, Rocky and Appalachian Mountains, Appalachian mountains. The river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana. The main stem is entirely within the United States; the total drainage basin is , of which only about one percent is in Canada. The Mississippi ranks as the world's List of rivers by discharge, tenth-largest river by discharge flow, and the largest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Picea Critchfieldii
''Picea critchfieldii'' is an extinct species of spruce tree formerly present on the landscape of North America, where it was once widely distributed throughout the southeastern United States. Plant macrofossil evidence reveals that this tree became extinct during the Late Quaternary period of Earth's history. At present, this is the only documented plant extinction from this geologic era. Hypotheses as to what specifically drove the extinction remain unresolved, but rapid and widespread climatic changes coincided with ''Picea critchfieldii'''s decline and ultimate extinction. History and classification ''Picea critchfieldii'' was first described by Stephen T. Jackson and Chengyu Weng in a 1999 paper titled, "Late Quaternary Extinction of a Tree Species in Eastern North America" published in the journal ''Proceedings of the National Academy of Sciences of the United States of America''. They coined the specific epithet ''critchfieldii'' as a patronym honoring botanist William B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoendemic
Paleoendemism along with neoendemism is a possible subcategory of endemism. Paleoendemism refers to species that were formerly widespread but are now restricted to a smaller area. Neoendemism refers to species that have recently arisen, such as through divergence and reproductive isolation or through hybridization and polyploidy in plants. Etymology The first part of the word, paleo, comes from the Greek word ''palaiós, meaning "ancient".'' The second part of the word, ''endemism'' is from Neo-Latin ''endēmicus'', from Greek ενδήμος, ''endēmos'', "native". ''Endēmos'' is formed of ''en'' meaning "in", and ''dēmos'' meaning "the people". Causes Changes in climate are thought to be the driving force in creating paleoendemic species, generally due to habitat loss. Regions where the climate has remained relatively stable form refugia which are more likely to be endemic hotspots today. This applies to both neoendemism and paleoendemism. However, paleoendemism differs a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
