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Kastanozems
Kastanozem (also known as "chestnut soil") is one of the 32 Reference Soil Groups of the World Reference Base for Soil Resources (WRB). These soils are brighter than Chernozems, and are related to the Mollisols in the USDA soil taxonomy. They are rich in humus, and originally covered with early maturing native grasslands vegetation, which produces a characteristic brown surface layer in the first meter in depth. They have a relative high level of available calcium ions bound to soil particles and can have a petrocalcic horizon between 25 and 100 cm thick. Kastanozems are found in relatively dry zones with 200 to 450 mm of rainfall a year. The name is derived from the Russian term 'каштановые почвы', where 'каштановые' is a shade of brown derived from the word "каштан" (''kashtan''), "chestnut" and refers to the color of its husk Husk (or hull) in botany is the outer shell or coating of a seed. In the United States, the term husk oft ...
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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 International Union of Soil Sciences (IUSS). WRB, 4th edition (2022) Background History Since the 19th century, several countries developed national soil classification systems. During the 20th century, the need for an international soil classification system became more and more obvious. From 1971 to 1981, the Food and Agriculture Organization ( FAO) and UNESCO published the Soil Map of the World, 10 volumes, scale 1 : 5 M). The Legend for this map, published in 1974 under the leadership of Rudi Dudal, became the FAO soil classification. Many ideas from national soil classification systems were brought together in this worldwide-applicable system, among them the idea of diagnostic horizons as established in the '7th approximation t ...
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Chernozems
Chernozem (from rus, чернозём, p=tɕɪrnɐˈzʲɵm, r=chernozyom; "black ground"), also called black soil, is a black-colored soil containing a high percentage of humus (4% to 16%) and high percentages of phosphorus and ammonia compounds. Chernozem is very soil fertility, fertile soil and can produce high agricultural yields with its high moisture storage capacity. Chernozems are a Reference Soil Group of the World Reference Base for Soil Resources (WRB). Distribution The name comes from the Russian terms for black and soil, earth or land (''chorny'' + ''zemlya''). The soil, rich in organic matter presenting a black color, was first identified by Russian geologist Vasily Dokuchaev in 1883 in the tallgrass steppe or prairie of European Russia. Chernozem cover about 230 million hectares of land. There are two "chernozem belts" in the world. One is the Eurasian steppe which extends from eastern Croatia (Slavonia), along the Danube (northern Serbia, northern Bulgaria (Da ...
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Mollisols
Mollisol is a soil type which has deep, high organic matter, nutrient-enriched surface soil (a horizon), typically between 60 and 80 cm in depth. This fertile surface horizon, called a mollic epipedon, is the defining diagnostic feature of Mollisols. Mollic epipedons are created by long-term addition of organic materials derived from plant roots and typically have soft, granular soil structure. Mollisols also occur in savannahs and mountain valleys (such as Central Asia, and the North American Great Plains). These environments have historically been strongly influenced by fire and abundant pedoturbation from organisms such as ants and earthworms. It was estimated that in 2003, only 14 to 26 percent of grassland ecosystems still remained in a relatively natural state (that is, they were not used for agriculture due to the fertility of the horizon). Globally, they represent ~7% of ice-free land area. As the world's agriculturally most productive soil order, the Mollisols repres ...
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USDA Soil Taxonomy
USDA soil taxonomy (ST) developed by the United States Department of Agriculture and the National Cooperative Soil Survey provides an elaborate classification of soil types according to several parameters (most commonly their properties) and in several levels: ''Order'', ''Suborder'', ''Great Group'', ''Subgroup'', ''Family'', and '' Series''. The classification was originally developed by Guy Donald Smith, former director of the U.S. Department of Agriculture's soil survey investigations. Discussion A taxonomy is an arrangement in a systematic manner; the USDA soil taxonomy has six levels of classification. They are, from most general to specific: order, suborder, great group, subgroup, family and series. Soil properties that can be measured quantitatively are used in this classification system – they include: depth, moisture, temperature, texture, structure, cation exchange capacity, base saturation, clay mineralogy, organic matter content and salt content. There are 12 s ...
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Brown
Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model used to project colors onto television screens and computer monitors, brown combines red and green. The color brown is seen widely in nature, wood, soil, human hair color, eye color and skin pigmentation. Brown is the color of dark wood or rich soil. According to public opinion surveys in Europe and the United States, brown is the least favorite color of the public; it is often associated with plainness, the rustic, feces, and poverty. More positive associations include baking, warmth, wildlife, and the autumn. Etymology The term is from Old English , in origin for any dusky or dark shade of color. The first recorded use of ''brown'' as a color name in English was in 1000. The Common Germanic adjectives ''*brûnoz and *brûnâ'' meant ...
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Chestnut
The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. They are native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce. The unrelated horse chestnuts (genus ''Aesculus'') are not true chestnuts, but are named for producing nuts of similar appearance that are mildly poisonous to humans. True chestnuts should also not be confused with water chestnuts, which are tubers of an aquatic herbaceous plant in the sedge family Cyperaceae. Other species commonly mistaken for chestnut trees are the chestnut oak (''Quercus prinus'') and the American beech ('' Fagus grandifolia''),Chestnut Tree
in chestnuttree.net.
both of which are also in the Fagaceae family.

Husk
Husk (or hull) in botany is the outer shell or coating of a seed. In the United States, the term husk often refers to the leafy outer covering of an ear of maize (corn) as it grows on the plant. Literally, a husk or hull includes the protective outer covering of a seed, fruit, or vegetable. It can also refer to the exuvia of insects or other small animals left behind after moulting. In cooking, hull can also refer to other waste parts of fruits and vegetables, notably the cap or sepal of a strawberry. The husk of a legume and some similar fruits is called a pod. Husking and dehulling Husking of corn is the process of removing its outer layers, leaving only the cob or seed rack of the corn. Dehulling is the process of removing the hulls (or chaff) from beans and other seeds. This is sometimes done using a machine known as a huller. To prepare the seeds to have oils extracted from them, they are cleaned to remove any foreign objects. Next, the seeds have their hulls, ...
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