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Amanit School
Amanit is a ''tabia'' or municipality in the Dogu'a Tembien district of the Tigray Region of Ethiopia. The ''tabia'' centre is Addi Qeshofo village, located approximately 15 km to the southeast of the ''woreda'' town Hagere Selam (as the crow flies). Geography The ''tabia'' stretches down southbound over an elongated ridge between Inda Sillasie River and Addi Keshofo River towards Giba River. The highest place is a hill east of Gudeli (2230 m a.s.l.) and the lowest place at the junction of Inda Sillasie and Giba Rivers (1448 m a.s.l.). Geology The two main geological formations are Antalo Limestone in most of the ''tabia'', and Adigrat Sandstone on the slopes towards the river gorges. Quaternary alluvium and freshwater tufa occur in the valley bottoms. Geomorphology and soils The main geomorphic units, with corresponding soil types are: * Gently rolling Antalo Limestone plateau, holding cliffs and valley bottoms on limestone ** Associated soil types *** shallow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boswellia Papyrifera
''Boswellia papyrifera'', also known as the Sudanese frankincense, is a species of flowering plant and frankincense that is native to Ethiopia, Eritrea and Sudan. The tree is cultivated in Ethiopia because of its valuable resin. The incense is characterized by a fresh lemon-pine scent and is therefore highly esteemed. In Ethiopia where it is called ''itan zaf'', it comes in semi-translucent yellow tears. The gum resin of ''Boswellia papyrifera'' coming from Ethiopia, Sudan and eastern Africa is believed to be the main source of frankincense of antiquity. Chemical constituents In studies conducted on the chemical properties of the oleo-gum resin of ''B. papyrifera'', it was shown to contain a high concentration of octyl acetate (57.1–65.7%) and N-octanol (3.4–8.8%), the former accounting for its citric note. The species also contain diterpenes Diterpenes are a class of chemical compounds composed of four isoprene units, often with the molecular formula C20H32. They are b ... [...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, ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Infiltration
Infiltration is the process by which water on the ground surface enters the soil. It is commonly used in both hydrology and soil sciences. The infiltration capacity is defined as the maximum rate of infiltration. It is most often measured in meters per day but can also be measured in other units of distance over time if necessary. The infiltration capacity decreases as the soil moisture content of soils surface layers increases. If the precipitation rate exceeds the infiltration rate, runoff will usually occur unless there is some physical barrier. Infiltrometers, permeameters and rainfall simulators are all devices that can be used to measure infiltration rates. Infiltration is caused by multiple factors including; gravity, capillary forces, adsorption and osmosis. Many soil characteristics can also play a role in determining the rate at which infiltration occurs. Factors that affect infiltration Precipitation Precipitation can impact infiltration in many ways. The a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic ('' genetic variability''), species ('' species diversity''), and ecosystem ('' ecosystem diversity'') level. Biodiversity is not distributed evenly on Earth; it is usually greater in the tropics as a result of the warm climate and high primary productivity in the region near the equator. Tropical forest ecosystems cover less than 10% of earth's surface and contain about 90% of the world's species. Marine biodiversity is usually higher along coasts in the Western Pacific, where sea surface temperature is highest, and in the mid-latitudinal band in all oceans. There are latitudinal gradients in species diversity. Biodiversity generally tends to cluster in hotspots, and has been increasing through time, but will be likely to slow in the future as a primary result of deforestation. It encompasses the evolutionary, ecological, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exclosure
An exclosure, in an area being used extensively for grazing, is a limited area from which unwanted browsing animals, such as domestic cattle or wildlife such as deer, are excluded by fencing or other means. Environmental protection Most commonly, exclosures are areas that are set aside for regreening. Wood harvesting and livestock range are not allowed there. Effects on environment The establishment of an exclosure has positive effects on: * biodiversity * water infiltration * protection from flooding * sediment deposition * carbon sequestration Economic benefits In developing countries, people commonly have economic benefits from these exclosures through grass harvesting, beekeeping and other non-timber forest products. The local inhabitants also consider it as “land set aside for future generations”. Carbon credits Exclosures have as an additional benefit that the surrounding communities may receive carbon credits for the sequestered CO2, as part of a carbon o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
May Hib'o
May Hib’o is an exclosure located in the Dogu'a Tembien ''woreda'' of the Tigray Region in Ethiopia. The exclosure holds a 70-metre long cave. Environmental characteristics * Area: 50 ha * Average slope gradient: 35% * Aspect: the exclosure is oriented towards the southwest and the north (both sides of a gorge) * Minimum altitude: 1896 metres * Maximum altitude: 2146 metres * Lithology: Antalo Limestone * 2017: support by the EthioTrees project Management As a general rule, cattle ranging and wood harvesting are not allowed. The grasses are harvested once yearly and taken to the homesteads of the village to feed livestock. Benefits for the community Setting aside such areas fits with the long-term vision of the communities were ''hiza’iti'' lands are set aside for use by the future generations. It has also direct benefits for the community: * improved ground water availability * honey production * climate ameliorator (temperature, moisture) * the sequestered carbon (in to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amanit Community Water Pump
Amanit is a ''tabia'' or municipality in the Degua Tembien, Dogu'a Tembien district of the Tigray Region of Ethiopia. The ''tabia'' centre is Addi Qeshofo village, located approximately 15 km to the southeast of the ''woreda'' town Hagere Selam (Degua Tembien), Hagere Selam (as the crow flies). Geography The ''tabia'' stretches down southbound over an elongated ridge between Inda Sillasie River and Addi Keshofo River towards Giba River. The highest place is a hill east of Gudeli (2230 m a.s.l.) and the lowest place at the junction of Inda Sillasie and Giba Rivers (1448 m a.s.l.). Geology The two main geological formations are Antalo Limestone in most of the ''tabia'', and Adigrat Sandstone on the slopes towards the river gorges. Quaternary alluvium and freshwater tufa occur in the valley bottoms. Geomorphology and soils The main geomorphic units, with corresponding soil types are: * Gently rolling Antalo Limestone plateau, holding cliffs and valley bottoms on limeston ... [...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] |
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 w ... [...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 soil texture, 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 compose ... [...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 ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
