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Walta (Dogu'a Tembien)
Walta is a municipality in the Dogu'a Tembien district of the Tigray Region of Ethiopia. The ''tabia'' centre is in Da’erere village, located approximately 7 km to the south of the ''woreda'' town Hagere Selam. Geography The ''tabia'' stretches down from the foot of the Tsatsen ridge escarpment towards Giba River. It is further bound by three gorges: Gra Adiam/Bitchoqo in the east, Giba River in the south, and Zeyi River in the west. The highest peak is near the top of Tsatsen plateau (2760 m a.s.l.) and the lowest place at the confluence of Giba and Zeyi Rivers (1400 m a.s.l.), which have a difference in elevation of nearly 1400 metres. Geology From the higher to the lower locations, the following geological formations are present: * Upper basalt * Interbedded lacustrine deposits * Lower basalt * Amba Aradam Formation * Antalo Limestone * Adigrat Sandstone * Quaternary alluvium and freshwater tufa Geomorphology and soils The main geomorphic units, wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethiopia
Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the north, Djibouti to the northeast, Somalia to the east and northeast, Kenya to the south, South Sudan to the west, and Sudan to the northwest. Ethiopia has a total area of . As of 2022, it is home to around 113.5 million inhabitants, making it the 13th-most populous country in the world and the 2nd-most populous in Africa after Nigeria. The national capital and largest city, Addis Ababa, lies several kilometres west of the East African Rift that splits the country into the African and Somali tectonic plates. Anatomically modern humans emerged from modern-day Ethiopia and set out to the Near East and elsewhere in the Middle Paleolithic period. Southwestern Ethiopia has been proposed as a possible homeland of the Afroasiatic langua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomorphic
Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform and terrain history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphologists work within disciplines such as physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field. Overview Earth's surface is modified by a combination of surface processes that shape landscapes, and geologic processes that cause tectonic uplift and subsidence, and shape the coastal geography. Surface processes compr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage System (geomorphology)
In geomorphology, drainage systems, also known as river systems, are the patterns formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and hydrologists often view streams as part of drainage basins (and sub-basins). This is the topographic region from which a stream receives runoff, throughflow, and its saturated equivalent, groundwater flow. The number, size, and shape of the drainage basins varies and the larger and more detailed the topographic map, the more information is available. Drainage patterns Per the lie of channels, drainage systems can fall into one of several categories, known as drainage patterns. These depend on the topography and geology of the land. All forms of transitions can occur between parallel, dendritic, and trellis patterns. Accordant versus discordant drainage patterns A drai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nile
The Nile, , Bohairic , lg, Kiira , Nobiin language, Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered the List of rivers by length, longest river in the world, though this has been contested by research suggesting that the Amazon River is slightly longer.Amazon Longer Than Nile River, Scientists Say Of the world's major rivers, the Nile is one of the smallest, as measured by annual flow in cubic metres of water. About long, its drainage basin covers eleven countries: the Democratic Republic of the Congo, Tanzania, Burundi, Rwanda, Uganda, Kenya, Ethiopia, Erit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tekezé River
The Tekezé or Täkkäze River ( amh, ተከዜ, ti, ተከዘ; originally meaning "river" in Ge’ez, ), also spelled Takkaze, is a major river of Ethiopia. For part of its course it forms a section of the westernmost border of Ethiopia and Eritrea. The river is also known as the Setit () in Eritrea, western Ethiopia, and eastern Sudan. According to materials published by the Ethiopian Central Statistical Agency, the Tekezé River is long. The canyon which it has created is the deepest in Africa and one of the deepest in the world, at some points having a depth of over 2000 meters (6,562 feet). Course The Tekezé River rises in the central Ethiopian Highlands near Mount Qachen within Lasta, from where it flows west, north, then west again, forming the westernmost border of Ethiopia and Eritrea from the confluence of the Tomsa with the Tekezé at to the tripoint between the two countries and Sudan at . After entering northeastern Sudan at the tripoint it joins the Atbarah ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loam Soils (Eutric [[Regosol]] And [[Cambisol]])
** Inclusions
*** Shallow, Dry Soils With Very High Amounts Of Stones (Leptic And Skeletic [[Cambisol]] And [[Regosol]])
*** Deep, Dark Cracking [[clay]]s With Good Fertility, But Problems Of [[waterlogging (agriculture)
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 h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvisol
A fluvisol in the World Reference Base for Soil Resources (WRB) is a genetically young soil in alluvial deposits . Apart from river sediments, they also occur in lacustrine and marine deposits. Fluvisols correlate with fluvents and fluvaquents of the USDA soil taxonomy. The good natural fertility of most fluvisols and their attractive dwelling sites on river levees and higher parts in marine landscapes were recognized in prehistoric times. Fluvisols are found on alluvial plains, river fans, valleys and tidal marshes on all continents and in all climate zones. Under natural conditions periodical flooding is fairly common. The soils have a clear evidence of stratification. Soil horizons are weakly developed, but a distinct topsoil horizon may be present. Many dryland crops are grown on fluvisols, normally with some form of water control. On tropical Fluvisols with satisfactory irrigation and drainage paddy rice cultivation is widespread. Some coastal lowlands have fluvisols wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silt 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 |
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 calciu ... [...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] |
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 |
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] |
