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Acrisols
An Acrisol is a Reference Soil Group of the World Reference Base for Soil Resources (WRB). It has a clay-rich subsoil and is associated with humid, tropical climates, such as those found in Brazil, and often supports forested areas. In the USDA soil taxonomy, Acrisols correspond to the Humult, Udult and Ustult suborders of the Ultisols and also to Oxisols with a kandic horizon and to some Alfisols.CHESWORTH, WARD. Encyclopedia of Soil Science. 2001. pp. 22-24 The Acrisols low fertility and toxic amounts of aluminium pose limitations to its agricultural use, favouring in many places its use for silviculture, low intensity pasture and protected areas. Crops that can be successfully cultivated, if climate allows, include tea, rubber tree, oil palm, coffee and sugar cane Sugarcane or sugar cane is a species of (often hybrid) tall, perennial grass (in the genus '' Saccharum'', tribe Andropogoneae) that is used for sugar production. The plants are 2–6 m (6–20 ft) tall wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stagnosol
A Stagnosol in the World Reference Base for Soil Resources (WRB) is soil with strong mottling of the soil profile due to redox processes caused by stagnating surface water. Stagnosols are periodically wet and mottled in the topsoil and subsoil, with or without concretions and/or bleaching. The topsoil can also be completely bleached (albic horizon). A common name in many national classification systems for most Stagnosols is pseudogley. In the USDA soil taxonomy, many of them belong to the Aqualfs, Aquults, Aquents, Aquepts and Aquolls. They are developed in a wide variety of unconsolidated materials like glacial till, and loamy aeolian, alluvial and colluvial deposits and physically weathered siltstone. Stagnosols occur on flat to gently sloping land in cool temperate to subtropical regions with humid to perhumid climate conditions. The agricultural suitability of Stagnosols is limited because of their oxygen deficiency resulting from stagnating water above a dense subsoil. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silviculture
Silviculture is the practice of controlling the growth, composition/structure, and quality of forests to meet values and needs, specifically timber production. The name comes from the Latin ('forest') and ('growing'). The study of forests and woods is termed ''silvology''. Silviculture also focuses on making sure that the treatment(s) of forest stands are used to conserve and improve their productivity. Generally, silviculture is the science and art of growing and cultivating forest crops, based on a knowledge of silvics (the study of the life-history and general characteristics of forest trees and stands, with particular reference to local/regional factors). The focus of silviculture is the control, establishment and management of forest stands. The distinction between forestry and silviculture is that silviculture is applied at the stand-level, while forestry is a broader concept. Adaptive management is common in silviculture, while forestry can include natural/conserved land ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Type
A soil type is a taxonomic unit in soil science. All soils that share a certain set of well-defined properties form a distinctive soil type. Soil type is a technical term of soil classification, the science that deals with the systematic categorization of soils. Every soil of the world belongs to a certain soil type. Soil type is an abstract term. In nature, you will not find soil types. You will find soils that belong to a certain soil type. In hierarchical soil classification systems, soil types mostly belong to the higher or intermediate level. A soil type can normally be subdivided into subtypes, and in many systems several soil types can be combined to entities of higher category. However, in the first classification system of the United States (Whitney, 1909), the soil type was the lowest level and the mapping unit. For the definition of soil types, some systems use primarily such characteristics that are the result of soil-forming processes (pedogenesis). An example is the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Horizon
A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. These may be described both in absolute terms (particle size distribution for texture, for instance) and in terms relative to the surrounding material, i.e. 'coarser' or 'sandier' than the horizons above and below. The identified horizons are indicated with symbols, which are mostly used in a hierarchical way. Master horizons (main horizons) are indicated by capital letters. Suffixes, in form of lowercase letters and figures, further differentiate the master horizons. There are many different systems of horizon symbols in the world. No one system is more correct—as artificial constructs, their utility lies in their ability to accurately describe local conditions in a consistent manner. Due to the different definitions of the horizon symb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Cane
Sugarcane or sugar cane is a species of (often hybrid) tall, perennial grass (in the genus ''Saccharum'', tribe Andropogoneae) that is used for sugar production. The plants are 2–6 m (6–20 ft) tall with stout, jointed, fibrous stalks that are rich in sucrose, which accumulates in the stalk internodes. Sugarcanes belong to the grass family, Poaceae, an economically important flowering plant family that includes maize, wheat, rice, and sorghum, and many forage crops. It is native to the warm temperate and tropical regions of India, Southeast Asia, and New Guinea. The plant is also grown for biofuel production, especially in Brazil, as the canes can be used directly to produce ethyl alcohol (ethanol). Grown in tropical and subtropical regions, sugarcane is the world's largest crop by production quantity, totaling 1.9 billion tonnes in 2020, with Brazil accounting for 40% of the world total. Sugarcane accounts for 79% of sugar produced globally (most of the rest is ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffea
''Coffea'' is a genus of flowering plants in the Family (biology), family Rubiaceae. ''Coffea'' species are shrubs or small trees native to tropical and southern Africa and tropical Asia. The seeds of some species, called coffee beans, are used to flavor various beverages and products. The fruits, like the seeds, contain a large amount of caffeine, and have a distinct sweet taste and are often juiced. The plant ranks as one of the world's most valuable and widely traded commodity crops and is an important export product of several countries, including those in Central and South America, the Caribbean and Africa. Cultivation and use There are over 120 species of ''Coffea'', which is grown from seed. The two most popular are ''Coffea arabica'' (commonly known simply as "Arabica"), which accounts for 60–80% of the world's coffee production, and ''Coffea canephora'' (known as "Robusta coffee, Robusta"), which accounts for about 20–40%. '' C. arabica'' is preferred for its s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Palm
''Elaeis'' () is a genus of palms containing two species, called oil palms. They are used in commercial agriculture in the production of palm oil. The African oil palm ''Elaeis guineensis'' (the species name ''guineensis'' referring to its country of origin) is the principal source of palm oil. It is native to west and southwest Africa, occurring between Angola and Gambia. The American oil palm ''Elaeis oleifera'' () is native to tropical Central and South America, and is used locally for oil production. Description Mature palms are single-stemmed, and can grow well over tall. The leaves are pinnate, and reach between long. The flowers are produced in dense clusters; each individual flower is small, with three sepals and three petals. The palm fruit is reddish, about the size of a large plum, and grows in large bunches. Each fruit is made up of an oily, fleshy outer layer (the pericarp), with a single seed (the palm kernel), also rich in oil. Species The two species, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubber Tree
''Hevea brasiliensis'', the Pará rubber tree, ''sharinga'' tree, seringueira, or most commonly, rubber tree or rubber plant, is a flowering plant belonging to the spurge family Euphorbiaceae originally native to the Amazon basin, but is now pantropical in distribution due to introductions. It is the most economically important member of the genus '' Hevea'' because the milky latex extracted from the tree is the primary source of natural rubber. Description ''H. brasiliensis'' is a tall deciduous tree growing to a height of up to in the wild, but cultivated trees are usually much smaller because drawing off the latex restricts the growth of the tree. The trunk is cylindrical and may have a swollen, bottle-shaped base. The bark is some shade of brown, and the inner bark oozes latex when damaged. The leaves have three leaflets and are spirally arranged. The inflorescence include separate male and female flowers. The flowers are pungent, creamy-yellow and have no petals. The fru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camellia Sinensis
''Camellia sinensis'' is a species of evergreen shrub or small tree in the flowering plant family Theaceae. Its leaves and leaf buds are used to produce the popular beverage, tea. Common names include tea plant, tea shrub, and tea tree (not to be confused with ''Melaleuca alternifolia'', the source of tea tree oil, or the genus ''Leptospermum'' commonly called tea tree). White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one of two major varieties grown today, ''C. sinensis'' var. ''sinensis'' and ''C. s.'' var. ''assamica'', but are processed differently to attain varying levels of oxidation with black tea being the most oxidized and green being the least. Kukicha (twig tea) is also harvested from ''C. sinensis'', but uses twigs and stems rather than leaves. Nomenclature and taxonomy The generic name ''Camellia'' is taken from the Latinized name of Rev. Georg Kamel, SJ (1661–1706), a Moravian-born Jesuit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfisol
Alfisols are a soil order in USDA soil taxonomy. Alfisols form in semi-arid to humid areas, typically under a hardwood forest cover. They have a clay-enriched subsoil and relatively high native fertility. "Alf" refers to aluminium (Al) and iron (Fe). Because of their productivity and abundance, Alfisols represent one of the more important soil orders for food and fiber production. They are widely used both in agriculture and forestry, and are generally easier to keep fertile than other humid-climate soils, though those in Australia and Africa are still very deficient in nitrogen and available phosphorus. Those in monsoonal tropical regions, however, have a tendency to acidify when heavily cultivated, especially when nitrogenous fertilizers are used. In the World Reference Base for Soil Resources (WRB), most Alfisols are classified as Luvisols or Lixisols, but some are classed as Retisols or Nitisols. Aqualfs are mainly Stagnosols or Planosols. Alfisols with a natric horizon are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxisol
Oxisols are a soil order in USDA soil taxonomy, best known for their occurrence in tropical rain forest within 25 degrees north and south of the Equator. In the World Reference Base for Soil Resources (WRB), they belong mainly to the ferralsols, but some are plinthosols or nitisols. Some oxisols have been previously classified as laterite soils. Formation The main processes of soil formation of oxisols are weathering, humification and pedoturbation due to animals. These processes produce the characteristic soil profile. They are defined as soils containing ''at all depths'' no more than ten percent weatherable minerals, and low cation exchange capacity. Oxisols are always a red or yellowish color, due to the high concentration of iron(III) and aluminium oxides and hydroxides. They also contain quartz and kaolin, plus small amounts of other clay minerals and organic matter. Etymology The word "oxisol" comes from ''"oxide"'' in reference to the dominance of oxide minerals such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
