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Arak Gorges
The Arak gorges are a series of desert gorges located in Tamanrasset Province, Algeria. The gorges are roughly 330 kilometres from the city of Tamanrasset. Carved by ancient river activity, the canyon walls vary in height from 250 to 500 m (800 to 1600 ft), and the canyon base is now a dry wadi. Despite the extremely dry climate (only 60 to 75 mm of rain per year), hardy desert plants and animals survive in the gorges. Examples include the red-headed rock agama, wheatear birds, and small vultures. There are no permanent human settlements in the gorges, though stone tools Stone tools have been used throughout human history but are most closely associated with prehistoric cultures and in particular those of the Stone Age. Stone tools may be made of either ground stone or knapped stone, the latter fashioned by a c ... and burial mounds indicate the occasional human presence throughout history. Gallery File:Carte topographique des gorges d'Arak.png, Topographic map of the reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tamanrasset Province
Tamanrasset or Tamanghasset ( ''Wilāya Tamanrāssat'', ) is a province (''wilaya'') in southern Algeria. It is named after its province seat, Tamanrasset. The province is the home of two national parks: Ahaggar National Park and Tassili n'Ajjer National Park. It is the largest province in Algeria, with an area of 336,839 km2. Geography Tamanrasset is located in the deep southern region of Algeria, approximately 2,000 kilometers south of Algiers. It is bordered by In Salah Province on the north, Illizi Province on the northeast, Djanet Province on the east, In Guezzam Province on the south, Bordj Badji Mokhtar Province on the southwest, and Adrar Province on the west. It also borders Agadez Region in Niger to the southeast. Tamanrasset is located in the heart of the Algerian Desert of the Sahara. In general, the province has a hot desert climate (Köppen climate classification ''BWh''), with very hot summers and mild winters, though more mountainous areas, such as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algeria
Algeria, officially the People's Democratic Republic of Algeria, is a country in the Maghreb region of North Africa. It is bordered to Algeria–Tunisia border, the northeast by Tunisia; to Algeria–Libya border, the east by Libya; to Algeria–Niger border, the southeast by Niger; to Algeria–Western Sahara border, the southwest by Mali, Mauritania, and Western Sahara; to Algeria–Morocco border, the west by Morocco; and to the north by the Mediterranean Sea. The capital and List of cities in Algeria, largest city is Algiers, located in the far north on the Mediterranean coast. Inhabited since prehistory, Algeria has been at the crossroads of numerous cultures and civilisations, including the Phoenicians, Numidians, Ancient Rome, Romans, Vandals, and Byzantine Greeks. Its modern identity is rooted in centuries of Arab migrations to the Maghreb, Arab Muslim migration waves since Muslim conquest of the Maghreb, the seventh century and the subsequent Arabization, Arabisation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desert
A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the land surface of the Earth is arid or Semi-arid climate, semi-arid. This includes much of the Polar regions of Earth, polar regions, where little precipitation occurs, and which are sometimes called polar deserts or "cold deserts". Deserts can be classified by the amount of precipitation that falls, by the temperature that prevails, by the causes of desertification or by their geographical location. Deserts are formed by weathering processes as large variations in temperature between day and night strain the Rock (geology), rocks, which consequently break in pieces. Although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter, and the resulting frag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canyon
A canyon (; archaic British English spelling: ''cañon''), gorge or chasm, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency to cut through underlying surfaces, eventually wearing away rock layers as sediments are removed downstream. A river bed will gradually reach a baseline elevation, which is the same elevation as the body of water into which the river drains. The processes of weathering and erosion will form canyons when the river's headwaters and estuary are at significantly different elevations, particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering. A canyon may also refer to a rift between two mountain peaks, such as those in ranges including the Rocky Mountains, the Alps, the Himalayas or the Andes. Usually, a river or stream carves out such splits between mountains. Examples of mountain- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tamanrasset
Tamanrasset (; ), also known as Tamanghasset or Tamenghest, is an oasis city and capital of Tamanrasset Province in southern Algeria, in the Ahaggar Mountains. It is the chief city of the Algerian Tuareg. It is located at an altitude of . As of the 2008 census, it has a population of 92,635, up from 72,741 in 1998, with an annual growth rate of 2.5%. up to 116,521 in 2019. Tamanrasset was originally established as a military outpost to guard the trans-Saharan trade routes. Surrounded by the barren Sahara, very high temperatures of over have been recorded here. Tamanrasset is located at an oasis where citrus fruits, apricots, dates, almonds, cereals, corn, and figs are grown, despite the difficult climate. The Tuareg people were once the town's main inhabitants. Tamanrasset is a tourist attraction during the cooler months. Visitors are also drawn to the Museum of the Hoggar, which offers many exhibits depicting Tuareg life and culture. The city is served by Tamanrasset Airport ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wadi
Wadi ( ; ) is a river valley or a wet (ephemerality, ephemeral) Stream bed, riverbed that contains water only when heavy rain occurs. Wadis are located on gently sloping, nearly flat parts of deserts; commonly they begin on the distal portions of alluvial fans and extend to inland sabkhas or dry lakes. Permanent channels do not exist, due to lack of continual water flow. Water percolates down into the stream bed, causing an abrupt loss of energy and resulting in vast deposition. Wadis may develop dams of sediment that change the stream patterns in the next flash flood. Wadis tend to be associated with centers of human population because sub-surface water is sometimes available in them. Nomadic and pastoral desert peoples will rely on seasonal vegetation found in wadis, even in regions as dry as the Sahara, as they travel in complex transhumance routes. The centrality of wadis to water – and human life – in desert environments gave birth to the distinct sub-field of wadi h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agama Agama
The common agama, red-headed rock agama or rainbow agama (''Agama agama'') is a species of lizard from the family Agamidae found in most of sub-Saharan Africa. To clear up centuries of historical confusion based on Linnaeus and other authors, Wagner et al. designated a neotype (numbered ZFMK 15222) for the species, using a previously described specimen from Cameroon in the collection of the Zoologisches Forschungsmuseum Alexander Koenig in Bonn. The species name was formerly applied to a paraphyletic collection of taxa (a so-called wastebasket); subsequent mitochondrial DNA analysis of various populations indicates they represent separate species.Leaché, A.D. et al. (2009)Phylogeny of the genus ''Agama'' based on mitochondrial DNA sequence data.''Bonner zoologische Beiträge'' 56(4) 273-78. Consequently, three former subspecies '' A. a. africana'', '' A. a. boensis'', and '' A. a. mucosoensis'' are now considered separate species, and ''A. a. savattieri'' is considered synonymou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheatear
The wheatears are passerine birds of the genus ''Oenanthe''. They were formerly considered to be members of the thrush family, Turdidae, but are now more commonly placed in the flycatcher family, Muscicapidae. This is an Old World group, but the northern wheatear has established a foothold in eastern Canada and Greenland and in western Canada and Alaska. Taxonomy The genus ''Oenanthe'' was introduced by the French ornithologist Louis Pierre Vieillot in 1816 with ''Oenanthe leucura'', the black wheatear, as the type species. The genus formerly included fewer species but molecular phylogenetic studies of birds in the Old World flycatcher family Muscicapidae found that the genus ''Cercomela'' was polyphyletic with five species, including the type species '' C. melanura'', phylogenetically nested within the genus ''Oenanthe''. This implied that ''Cercomela'' and ''Oenanthe'' were synonyms. The genus ''Oenanthe'' ( Vieillot, 1816) has taxonomic priority over ''Cercomela'' ( Bonap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vulture
A vulture is a bird of prey that scavenges on carrion. There are 23 extant species of vulture (including condors). Old World vultures include 16 living species native to Europe, Africa, and Asia; New World vultures are restricted to North and South America and consist of seven identified species, all belonging to the Cathartidae family. A particular characteristic of many vultures is a bald, unfeathered head. This bare skin is thought to keep the head clean when feeding, and also plays an important role in thermoregulation. Vultures have been observed to hunch their bodies and tuck in their heads in the cold, and open their wings and stretch their necks in the heat. They also urinate on themselves as a means of cooling their bodies. A group of vultures in flight is called a "kettle", while the term "committee" refers to a group of vultures resting on the ground or in trees. A group of vultures that are feeding is termed a "wake". Taxonomy Although New World vulture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stone Tool
Stone tools have been used throughout human history but are most closely associated with prehistoric cultures and in particular those of the Stone Age. Stone tools may be made of either ground stone or knapped stone, the latter fashioned by a craftsman called a flintknapper. Stone has been used to make a wide variety of tools throughout history, including arrowheads, spearheads, hand axes, and querns. Knapped stone tools are nearly ubiquitous in pre-metal-using societies because they are easily manufactured, the tool stone raw material is usually plentiful, and they are easy to transport and sharpen. The study of stone tools is a cornerstone of prehistoric archaeology because they are essentially indestructible and therefore a ubiquitous component of the archaeological record. Ethnoarchaeology is used to further the understanding and cultural implications of stone tool use and manufacture. Knapped stone tools are made from cryptocrystalline materials such as chert, f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landforms Of Algeria
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 in the landscape is known as topography. Landforms include hills, mountains, canyons, and valleys, as well as shoreline features such as bays, peninsulas, and seas, including submerged features such as mid-ocean ridges, volcanoes, and the great oceanic basins. Physical characteristics Landforms are categorized by characteristic physical attributes such as elevation, slope, orientation, structure stratification, rock exposure, and soil type. Gross physical features or landforms include intuitive elements such as berms, cliffs, hills, mounds, peninsulas, ridges, rivers, valleys, volcanoes, and numerous other structural and size-scaled (e.g. ponds vs. lakes, hills vs. mountains) elements including various kinds of inland and oceanic waterbodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
