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Mennewe
Simret is a ''tabia'' or municipality in the Tanqua Millash woreda of the Tigray Region, Ethiopia, which comprises the longest cave of Tigray in Zeyi, as well as Ras Alula’s birthplace in Mennewe. The ''tabia'' centre is in Dengolo village. Until January 2020, Simret belonged to the Dogu'a Tembien district. Geography The ''tabia'' occupies a massive ridge at the southwest of Dogu’a Tembien, between the Zeyi gorge and the large amphitheatre-like valley of Mennewe, through which the main road winds from the lowlands to the Tembien highlands. The southern boundary is the Giba river. The highest peak is at the northern end of the ''tabia'' (2710 m a.s.l.) and the lowest place at the confluence of Zikuli and Giba rivers (1395 m a.s.l.). The difference in elevation is more than 1300 metres. Geology From the higher to the lower locations, the following geological formations are present: * Upper basalt * Interbedded lacustrine deposits * Lower basalt * Amba Arada ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ras Alula
Ras Alula Engida ( gez, ራስ አሉላ እንግዳ) (1827 – 15 February 1897; also known by his horse name Abba Nega and by Alula Qubi) was an Ethiopian general and politician who successfully led Abyssinian battles against Ottoman Egypt, the Mahdists and Italy. He was one of the most important leaders of the Abyssinian forces during the 19th century. Ras Alula Described by Haggai Erlich as the "greatest leader whom Ethiopia produced since the death of Emperor Tewodros II in 1868." Ras Alula was referred to by Europeans as "the Garibaldi of Ethiopia". Early years Alula was born in Mennewe, a village in Tembien,the son of Engda Eqube, a farmer of modest origins. Haggai Erlich relates a story about Alula's childhood – "well known throughout Tigray": a group of people carrying baskets of bread to a wedding ceremony were stopped by a group of children led by the future ''Ras'', who demanded to know where they were going. "To the Castle of Ras Alula Wadi Qubi," they mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abuna Aregewi
Abuna (or Abune, which is the status constructus form used when a name follows: Ge'ez አቡነ ''abuna''/''abune'', 'our father'; Amharic and Tigrinya) is the honorific title used for any bishop of the Ethiopian Orthodox Tewahedo Church as well as of the Eritrean Orthodox Tewahedo Church. It was historically used solely for the head of the Coptic Orthodox Church in Ethiopia during the more than 1000 years when the Coptic Patriarchate of Alexandria appointed only one bishop at a time to serve its Ethiopian flock. When referred to without a name following, it is ''Abun'', and if a name follows, it becomes ''Abuna'' (e.g., ''Abuna Paulos''). History Historically the Abun of the Ethiopian Church was appointed by the Pope of Alexandria and Patriarch of All Africa, who had diocesan authority over Ethiopia and the rest of Africa, at the request of the Emperor and, in historic times, after paying a substantial fee to the Muslim government for the privilege. The Abun would be s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edaga Arbi Glacials
The Edaga Arbi Glacials are a Palaeozoic geological formation in Tigray (northern Ethiopia) and in Eritrea. The matrix is composed of grey, black and purple clays (locally silt), that contains rock fragments up to 6 metres across. Pollen dating yields a Late Carboniferous (~323 million years or Ma) to Early Permian (~295 Ma) age. Name and definition The name was coined by geologist D.B.Dow and colleagues They referred to the wide outcrops surrounding the town of Idaga Arbi. So far the nomenclature has not been proposed for recognition to the International Commission on Stratigraphy. Stratigraphic context The Edaga Arbi Glacials fill the bottom of north-south oriented valleys, that were carved by glaciers, into the Precambrian basement and in Early Palaeozoic sediments. These valleys were often several kilometres wide and tens of meters deep. Indeed, northern Ethiopia was glaciated in the Early Palaeozoic (Late Ordovician; ~445 Ma), and in the Late Palaeozoic ( Carboniferous- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giba River
Giba is a river of northern Ethiopia. It starts at the confluence of Genfel and Sulluh (which rises in the mountains of Mugulat) (3298 metres above sea level) and flows westward to the Tekezé River. Future Lake Giba will occupy the plain where Sulluh, Genfel and Agula'i Rivers meet, and hence be the future source of Giba River. Hydrography It is a confined river, locally meandering in its narrow alluvial plain, with a slope gradient of 7 metres per kilometre. With its tributaries, the river has cut a deep gorge. Tributaries Main tributaries, from downstream to upstream, are * Tanqwa ** Tsech'i River ** May Qoqah ** Arwadito ** Adawro River * May Selelo * Zikuli River * Gra Adiam River, also called Bitchoqo River * Zeyi River * Inda Sillasie River ** May Zegzeg *** May Harena *** May Sho'ate ** May Be'ati River * Addi Keshofo River * May Gabat * Inda Anbesa * Ruba Bich'i River * Hurura ** Afedena River *** May Ayni ** Shimbula * Ilala River * Qarano River * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non- tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand, for example, aragonite, which has mostly been created, over the past 500million years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Somewhat more rarely, sand may be composed of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luvisol
Luvisols are a group of soils, comprising one of the 32 Reference Soil Groups in the international system of soil classification, the World Reference Base for Soil Resources The World Reference Base for Soil Resources (WRB) is an international soil classification system for naming soils and creating legends for soil maps. The currently valid version is the fourth edition 2022. It is edited by a working group of the In ... (WRB). They are widespread, especially in temperate climates, and are generally fertile. Luvisols are widely used for agriculture. Distribution Luvisols cover 500–600 million ha of land area, mainly in the temperate zones. They form on a wide variety of mineral parent materials. In Mediterranean regions, the formation of hematite can produce red-coloured Chromic Luvisols. Description and formation The main characteristic of Luvisols is an argic horizon, a subsurface zone with higher clay content than the material above it. This typically arises as clay is was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loam
Loam (in geology and soil science) is soil composed mostly of sand ( particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–silt–clay, respectively. These proportions can vary to a degree, however, and result in different types of loam soils: sandy loam, silty loam, clay loam, sandy clay loam, silty clay loam, and loam. In the , textural classification triangle, the only soil that is not predominantly sand, silt, or clay is called "loam". Loam soils generally contain more nutrients, moisture, and |
Leptosol
A Leptosol in the World Reference Base for Soil Resources (WRB) is a very shallow soil over hard rock or a deeper soil that is extremely gravelly and/or stony. Leptosols cover approximately 1.7 billion hectares of the Earth's surface. They are found from the tropics to the cold polar regions and from sea level to the highest peaks. Leptosols are particularly widespread in mountain areas, notably in Asia, South America, northern Canada and Alaska; and in the Saharan and Arabian deserts. Elsewhere, Leptosols can be found on hard rocks or where erosion has kept pace with soil formation or removed the top of the soil. In the FAO soil classification for the UNESCO Soil Map of the World (1974) the Leptosols on calcareous rock were called Rendzinas, those on acid rock were Rankers. The very shallow, less than 10 cm deep, ''Lithic Leptosols'' in mountain regions are the most extensive Leptosols on Earth. Leptosols are unattractive soils for rainfed agriculture because of their i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertisol
A vertisol, or vertosol, is a soil type in which there is a high content of expansive clay minerals, many of them known as montmorillonite, that form deep cracks in drier seasons or years. In a phenomenon known as argillipedoturbation, alternate shrinking and swelling causes ''self-ploughing'', where the soil material consistently mixes itself, causing some vertisols to have an extremely deep A horizon and no B horizon. (A soil with no B horizon is called an ''A/C soil''). This heaving of the underlying material to the surface often creates a microrelief known as '' gilgai''. Vertisols typically form from highly basic rocks, such as basalt, in climates that are seasonally humid or subject to erratic droughts and floods, or that impeded drainage. Depending on the parent material and the climate, they can range from grey or red to the more familiar deep black (known as "black earths" in Australia, "black gumbo" in East Texas, "black cotton" soils in East Africa, and "vlei soils" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterlogging (agriculture)
Waterlogging water is the saturation of soil with water. Soil may be regarded as waterlogged when it is nearly saturated with water much of the time such that its air phase is restricted and anaerobic conditions prevail. In extreme cases of prolonged waterlogging, anaerobiosis occurs, the roots of mesophytes suffer, and the subsurface reducing atmosphere leads to such processes as denitrification, methanogenesis, and the reduction of iron and manganese oxides. All plants, including crops require air (specifically, oxygen) to respire, produce energy and keep their cells alive. In agriculture, waterlogging of the soil typically blocks air from getting in to the roots. With the exception of rice (''Oryza sativa''), most crops like maize and potato, are therefore highly intolerant to waterlogging. Plant cells use a variety of signals such the oxygen concentration, plant hormones like ethylene, energy and sugar status to acclimate to waterlogging-induced oxygen deprivation. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clay is the oldest known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, oft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regosol
A Regosol in the World Reference Base for Soil Resources (WRB) is very weakly developed mineral soil in unconsolidated materials. Regosols are extensive in eroding lands, in particular in arid and semi-arid areas and in mountain regions. Internationally, Regosols correlate with soil taxa that are marked by incipient soil formation such as Entisols in the USDA soil taxonomy or Rudosols and possibly some Tenosols in the Australian Soil Classification. The group of Regosols is a taxonomic rest group containing all soils that could not be accommodated in any of the other groups. Excluded from the Regosols are weakly developed soils that classify as Leptosols (very shallow soils), Arenosols (sandy soils) or Fluvisols (in recent alluvial deposits). These soils have AC- profiles. Profile development is minimal as a consequence of young age and/or slow soil formation. Land use and management of Regosols vary widely. Some Regosols are used for capital-intensive irrigated farming but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
