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  • softening point (mechanics)

    industrial glass: Viscosity: The softening point, at which the glass may slump under its own weight, is defined by a viscosity of 107.65 poise, the annealing point by 1013 poise, and finally the strain point by 1014.5 poise. Upon further cooling, viscosity increases rapidly to well beyond 1018 poise,…

  • softly-softly (primate)

    Potto, (Perodicticus potto), slow-moving tropical African primate. The potto is a nocturnal tree dweller found in rainforests from Sierra Leone eastward to Uganda. It has a strong grip and clings tightly to branches, but when necessary it can also move quickly through the branches with a smooth

  • softshell turtle (reptile)

    Softshell turtle, (family Trionychidae), any of about 30 turtle species characterized by a flattened shell. The shell lacks the epidermal scutes (large scales) characteristic of most turtles, as in the leatherback sea turtle (Dermochelys coriacea), and the bony architecture of the shell is reduced.

  • software (computing)

    Software, instructions that tell a computer what to do. Software comprises the entire set of programs, procedures, and routines associated with the operation of a computer system. The term was coined to differentiate these instructions from hardware—i.e., the physical components of a computer

  • Software Development Laboratories (global corporation)

    Oracle Corporation, global corporation that develops and markets computer software applications for business. The company is best known for its Oracle database software, a relational database management system, and for computer systems and software, such as Solaris and Java, acquired in its

  • software engineering (computer science)

    computer science: Software engineering: Software engineering is the discipline concerned with the application of theory, knowledge, and practice to building reliable software systems that satisfy the computing requirements of customers and users. It is applicable to small-, medium-, and large-scale computing systems and organizations. Software engineering uses…

  • software robot (computer science)

    Agent, a computer program that performs various actions continuously and autonomously on behalf of an individual or an organization. For example, an agent may archive various computer files or retrieve electronic messages on a regular schedule. Such simple tasks barely begin to tap the potential

  • software-as-a-service (computing)

    cloud computing: Cloud services and major providers: …set of services, sometimes called software as a service (SaaS), involves the supply of a discrete application to outside users. The application can be geared either to business users (such as an accounting application) or to consumers (such as an application for storing and sharing personal photographs). Another set of…

  • softwood (timber)

    tree: Popular classifications: …less parallel their scientific classification: softwoods are conifers, and hardwoods are dicotyledons. Hardwoods are also known as broadleaf trees. The designations softwood, hardwood, and broadleaf, however, are often imprecise. The wood of some hardwoods—for example, certain willows and poplars and the softest of all woods, balsa—is softer than that of…

  • softwood fibre (fibre)

    papermaking: Wood: …groups: coniferous trees, usually called softwoods, and deciduous trees, or hardwoods. Softwood cellulose fibres measure from about 2 to 4 millimetres (0.08 to 0.16 inch) in length, and hardwood fibres range from about 0.5 to 1.5 millimetres (0.02 to 0.06 inch). The greater length of softwood fibres contributes strength to…

  • Sofuku-ji (temple, Nagasaki, Japan)

    Nagasaki: The Sofuku-ji (Chinese Temple; 1629) is a fine example of Chinese Ming dynasty architecture, inhabited by Chinese Buddhist monks. A fine view of Nagasaki-kō is offered by the Glover Mansion, the home of a 19th-century British merchant and reputed to be the site of Giacomo Puccini’s…

  • Sofya Alekseyevna (regent of Russia)

    Sophia, regent of Russia from 1682 to 1689. The eldest daughter of Tsar Alexis (ruled 1645–76) and his first wife, Mariya Miloslavskaya, Sophia was tutored by the Belorussian monk Simeon Polotsky, from whom she received an exceptionally good education. When her brother Fyodor III died (April 27

  • Soga (people)

    Soga, an Interlacustrine Bantu-speaking people inhabiting the area east of the Nile River between Lakes Victoria and Kyoga. They are the fourth largest ethnic group in Uganda. Culturally, they are very similar to the Ganda, who inhabit the region immediately to the west. Prosperous by national

  • Soga Chokuan (Japanese painter)

    Soga Chokuan, Japanese painter who specialized in bird-and-flower pictures and founded the Soga family of artists. He is especially noted as a painter of fowl (as his son Chokuan II was noted as a painter of falcons). His brightly coloured, realistic bird-and-flower screen paintings are in the Hōki

  • Soga Emishi (Japanese feudal lord)

    Soga Emishi, a leader of the great Soga family of Japan, whose assumption of imperial prerogatives provoked a coup d’état that destroyed the power of the Soga house and marked the end of the Asuka period (552–645) of Japanese history. Under Emishi’s father, Soga Umako, the Soga family had begun to

  • Soga family (Japanese history)

    Soga family, Japanese aristocratic family preeminent in the 7th century and instrumental in introducing Buddhism to Japan. Soga Umako (d. 626) overcame the powerful Mononobe and Nakatomi clans, who supported the native Shintō religion over Buddhism, and contrived to have his niece proclaimed

  • Soga Iruka (Japanese feudal lord)

    Soga Iruka, a leader of the powerful Soga family of Japan, whose murder resulted in the return of governmental power to the emperor and the promulgation of a series of far-reaching reforms. In 587, after defeating the rival Mononobe clan, the Soga family completely dominated the imperial court.

  • Soga monogatari (Japanese literary work)

    Japanese literature: Kamakura period (1192–1333): …mid- to late 14th century: Soga monogatari, an account of the vendetta carried out by the Soga brothers, and Gikeiki (“Chronicle of Gikei”; Eng. trans. Yoshitsune), describing the life of the warrior Minamoto Yoshitsune. Though inartistically composed, these portraits of resourceful and daring heroes caught the imaginations of the Japanese,…

  • Soga Shōhaku (Japanese painter)

    Soga Shōhaku, Japanese painter of the mid-Tokugawa period (1603–1867) who tried to revive the brush-style drawing of the great masters of the Muromachi period (1338–1573). As a young man he studied painting under the guidance of Takada Keiho of the Kanō school (school of painting based on Chinese s

  • Soga Umako (Japanese feudal lord)

    Soga Umako, a leader of the Soga family of Japan, who was responsible for the destruction of the powerful Mononobe and Nakatomi clans and the ascendancy of the Soga to a position of supreme power. Umako was instrumental in introducing Buddhism into Japan. His influence helped spur the introduction

  • Soga, Tiyo (South African author)

    Tiyo Soga, Xhosa journalist, minister, translator, composer of hymns, and collector of black South African fables, legends, proverbs, history, praises, and customs. His translation of John Bunyan’s Pilgrim’s Progress (U-Hambo lom-Hambi, 1866) had almost as great an influence upon the Xhosa language

  • sogak kasa (Korean literature)

    Korean literature: Later Kory?: 12th century to 1392: The sogak kasa, or popular song texts, introduced in the chapters on music in the Kory? sa (“History of Kory?”) and handed down in the Akchang kasa (“Collection of Courtly Songs”), are another late Kory? genre. These songs were sung at court. Among them are songs…

  • Sogamoso (Colombia)

    Sogamoso, city, Boyacá departamento, east-central Colombia. It lies along the Chicamocha River in the Andean Cordillera (mountains) Oriental, at an elevation of 8,428 feet (2,569 m) above sea level. Once a sacred city of the pre-Columbian Chibcha Indians, Sogamoso is a commercial and manufacturing

  • Sogavare, Manasseh (prime minister of Solomon Islands)

    Solomon Islands: Efforts toward recovery and reform and the 2006 and 2010 general elections: …office and was replaced by Sogavare, who opposed the presence of RAMSI. Conflict arose between RAMSI and the government over one of the prime minister’s political appointments, and Sogavare threatened to expel the multinational force. A compromise was brokered late in the year, and RAMSI remained.

  • Sogdian (people)

    history of Central Asia: The Uighur empire: …to the Uighur land many Sogdians, whose growing influence on state affairs was resented by the Turkic Uighurs and led to Mouyu’s assassination.

  • Sogdian alphabet

    alphabet: The Aramaic alphabet: …sacred (pre-Islamic) Persian literature; (2) Sogdian, a script and language that constituted the lingua franca of Central Asia in the second half of the 1st millennium ce; (3) K?k Turki, a script used from the 6th to the 8th century ce by Turkish tribes living in the southern part of…

  • Sogdian art

    Sogdian art, rich body of pre-Muslim Central Asian visual arts that was created between roughly the 5th and 9th centuries and is represented most notably by finds at Pendzhikent and Varakhsha, town principalities in Sogdiana. Many cultural streams united there: the remains of Sāsānian culture, of

  • Sogdian language

    Iranian languages: The Middle Iranian stage: The oldest surviving Sogdian documents are the so-called Ancient Letters found in a watchtower on the Great Wall of China, west of Dunhuang, and dated at the beginning of the 4th century ce. Most of the religious literature written in Sogdian dates from the 9th and 10th centuries.…

  • Sogdiana (ancient country, Central Asia)

    Sogdiana, ancient country of Central Asia centring on the fertile valley of the Zeravshan River, in modern Uzbekistan. Excavations have shown that Sogdiana was probably settled between 1000 and 500 bc and that it then passed under Achaemenian rule. It was later attacked by Alexander the Great and

  • Sogdianus (king of Persia)

    Darius II Ochus: …throne from his half brother Secydianus (or Sogdianus), whom he then executed. Ochus, who had previously been satrap of Hyrcania, adopted the name of Darius on his accession; he was also known as Nothus (from the Greek nothos, meaning “bastard”). Darius was dominated by eunuchs and by his half sister…

  • sogenannte B?se, Das (work by Lorenz)

    Konrad Lorenz: …book, Das sogenannte B?se (1963; On Aggression), he argued that fighting and warlike behaviour in man have an inborn basis but can be environmentally modified by the proper understanding and provision for the basic instinctual needs of human beings. Fighting in lower animals has a positive survival function, he observed,…

  • Sōgetsu (school of floral art)

    Sōgetsu, 20th-century Japanese school of floral art that introduced the zen’ei (“avant-garde”) ikebana style in which freedom of expression is preeminent. Founded by Teshigahara Sōfū in 1927, the school rose to prominence after World War II. It appeals to contemporary tastes by largely

  • Soghomonian, Soghomon (Armenian composer)

    Komitas, ethnomusicologist and composer who created the basis for a distinctive national musical style in Armenia. Orphaned at age 11, he was sent to study liturgical singing at a seminary in Vagarshapat (now Ejmiadzin) in Armenia. He graduated in 1893 and adopted the name Komitas, that of a

  • Sōgi (Japanese poet)

    Iio Sōgi, Buddhist monk and greatest master of renga (linked verse), the supreme Japanese poet of his age. Sōgi was born of humble stock, and nothing is known of his career before 1457. His later writings suggest that, after serving as a Zen monk in Kyōto, he became, in his 30s, a professional r

  • Soglo, Nicéphore (president of Benin)

    Benin: Decolonization and independence: …and Kérékou was defeated by Nicéphore Soglo, a former cabinet member.

  • Soglow, Otto (American cartoonist)

    caricature and cartoon: 20th century: …concentration in a few lines; Otto Soglow’s stenographic vocabulary of forms for human bodies (perhaps slightly indebted to Burgess’ Goops) was so graphic that it could be used in minuscule dimensions with perfect legibility. On the other hand, Peter Arno’s large-scale and heavy outlines, despite simple straightforward design, made his…

  • Sogn Fjord (fjord, Norway)

    Sogn Fjord, fjord, western Norway. It is the longest and deepest fjord in Norway, and its mouth is located 45 miles (72 km) north of Bergen. Its length, from the offshore island of Outer Sula (Ytre Sula) in the North Sea to Skjolden, at the head of its longest branch, Lustra Fjord, is 128 miles

  • Sogne Fjord (fjord, Norway)

    Sogn Fjord, fjord, western Norway. It is the longest and deepest fjord in Norway, and its mouth is located 45 miles (72 km) north of Bergen. Its length, from the offshore island of Outer Sula (Ytre Sula) in the North Sea to Skjolden, at the head of its longest branch, Lustra Fjord, is 128 miles

  • sogno di Scipione, Il (work by Mozart)

    Wolfgang Amadeus Mozart: The Italian tours: …works, and an allegorical serenata, Il sogno di Scipione. Probably intended as a tribute to the Salzburg prince-archbishop, Count Schrattenbach, this work may not have been given until the spring of 1772, and then for his successor Hieronymus, Count Colloredo; Schrattenbach, a tolerant employer generous in allowing leave, died at…

  • S?gur og kvaedi (work by Benediktsson)

    Einar Benediktsson: …five volumes of Symbolist verse—S?gur og kvaedi (1897; “Stories and Poems”), Hafblik (1906; “Smooth Seas”), Hrannir (1913; “Waves”), Vogar (1921; “Billows”), Hvammar (1930; “Grass Hollows”)—show a masterful command of the language and the influence of his extensive travels, and they exemplify his patriotism, mysticism, and love of nature. A…

  • Sogut (Turkey)

    Osman I: …established a principality centred at S?güt. With S?güt as their base, Osman and the Muslim frontier warriors (Ghazis) under his command waged a slow and stubborn conflict against the Byzantines, who sought to defend their territories in the hinterland of the Asiatic shore opposite Constantinople (now Istanbul). Osman gradually extended…

  • Sohag (Egypt)

    Sūhāj, town and capital of Sūhāj mu?āfa?ah (governorate) in the Nile River valley of Upper Egypt. The town is located on the Nile’s western bank between Asyū? and Jirjā, immediately across from Akhmīm on the eastern bank. It has cotton-ginning, textile-weaving, and food-processing factories.

  • Sohag (governorate, Egypt)

    Sūhāj, mu?āfa?ah (governorate) in Upper Egypt, south of Asyū? and north of Qinā governorates. It is a ribbonlike stretch of the fertile Nile River valley about 60 miles (100 km) long. Through it the Nile flows in a roughly 13-mile- (21-km-) wide flat-bottomed valley hemmed in by limestone cliffs

  • S?hak (Korean history)

    S?hak, (Korean: “Western Learning”), in Korean history, the study of Western culture, introduced into Korea from the Chinese Ming and Ch’ing dynasties in the 17th and 18th centuries. In a broad sense, the term S?hak refers to the study of Western thought, religion, ethics, science, and technology.

  • Sohan complex (archaeology)

    Stone Age: South Asia: …former, which is called the Sohanian (or Sohan), has been reported from five successive horizons, each of which yields pebble tools that are associated with flake implements. Massive and crude in the earliest phases of the Sohanian, these implements reveal a progressive refinement in the younger horizons, where the evolved…

  • Sohanian complex (archaeology)

    Stone Age: South Asia: …former, which is called the Sohanian (or Sohan), has been reported from five successive horizons, each of which yields pebble tools that are associated with flake implements. Massive and crude in the earliest phases of the Sohanian, these implements reveal a progressive refinement in the younger horizons, where the evolved…

  • Sohano Island (islet, Northern Solomon Islands)

    Sohano Island, coral islet in Buka Passage (the body of water that separates Buka and Bougainville islands), northern Solomon Islands archipelago, southwestern Pacific Ocean. It is part of the autonomous region of Bougainville within Papua New Guinea and served as the provincial capital for several

  • Sohār (Oman)

    ?u?ār, town and port, northern Oman. It is situated about 120 miles (190 km) northwest of Muscat on the Al-Bā?inah coast of the Gulf of Oman. ?u?ār’s origins are prehistoric; it is located near the sites of several ancient copper mines, some possibly dating to 2500 bc. The town became an early

  • Sohlenkerbtal (geology)

    valley: Types of valleys: …a broad valley floor occurs, Sohlenkerbtal (meaning precisely a valley with such characteristics) is the prevailing form. Valleys of this kind develop under the influence of groundwater flow in Hawaii (see below Processes). Gutter-shaped valleys with convex sides and broad floors are called Kehltal; and broad, flat valleys of planation…

  • Sohlman, August (Swedish journalist)

    August Sohlman, journalist and publicist who was a leading figure in the mid-19th-century Pan-Scandinavian movement and a champion of the cultural and linguistic integrity of the Swedish minority in Russian-ruled Finland. As a journalist, Sohlman wrote for a number of the leading newspapers of

  • Sohlman, Per August Ferdinand (Swedish journalist)

    August Sohlman, journalist and publicist who was a leading figure in the mid-19th-century Pan-Scandinavian movement and a champion of the cultural and linguistic integrity of the Swedish minority in Russian-ruled Finland. As a journalist, Sohlman wrote for a number of the leading newspapers of

  • Sohm Abyssal Plain (plain, Atlantic Ocean)

    abyssal plain: In the North Atlantic the Sohm Plain alone has an area of approximately 900,000 square km (350,000 square miles). The plains are largest and most common in the Atlantic Ocean, less common in the Indian Ocean, and even rarer in the Pacific, where they occur mainly as the small, flat…

  • Sohn Kee-Chung (Korean athlete)

    Sohn Kee-Chung: The Defiant One: Officially known at the 1936 Berlin Games as Son Kitei, marathon runner Sohn Kee-Chung symbolized the fierce nationalistic tensions of the era. A native Korean, Sohn lived under the rule of Japan, which had annexed Korea in 1910. From an early age Sohn had chafed…

  • Sohn Kee-Chung: The Defiant One

    Officially known at the 1936 Berlin Games as Son Kitei, marathon runner Sohn Kee-Chung symbolized the fierce nationalistic tensions of the era. A native Korean, Sohn lived under the rule of Japan, which had annexed Korea in 1910. From an early age Sohn had chafed under Japanese domination. Though

  • Sohn, Der (work by Hasenclever)

    Walter Hasenclever: Hasenclever’s first play, Der Sohn (1914; “The Son”), concerning a youth who becomes a political revolutionary and brings about his father’s death, became the manifesto for the German post-World War I generation. It was followed by two antiwar plays, Der Retter (1915; “The Saviour”), about a poet who…

  • Soho (neighbourhood, London, England, United Kingdom)

    Soho, neighbourhood in the City of Westminster, London, that is bounded by Oxford Street (north), Charing Cross Road (east), Coventry Street and Piccadilly Circus (south), and Regent Street (west). The name of Soho derives from an old hunting cry. It was an area of farmlands in the Middle Ages and

  • Soho (neighbourhood, New York City, New York, United States)

    New York City: Manhattan: Soho (short for “south of Houston”) covers much of the old immigrant East Side and now has been matched by a Noho neighbourhood. To the west is Henry James’s Washington Square and beyond that Greenwich Village, formerly a haven for artists but today home to…

  • SOHO (satellite)

    Solar and Heliospheric Observatory (SOHO), satellite managed jointly by the European Space Agency (ESA) and the U.S. National Aeronautics and Space Administration (NASA) that is equipped with a battery of novel instruments to study the Sun. SOHO was launched by NASA on an Atlas rocket on Dec. 2,

  • Soho clubs

    The mid-1950s were do-it-yourself time for young singers and musicians throughout the world. In the United States, depending on the region of the country, the options were joining an electric-guitar bar band that played country music or blues or singing doo-wop on a street corner. In England, from

  • Sohr, Martin (German composer)

    Martin Agricola, composer, teacher, and writer on music, one of the first musicians to concern himself with the needs of the Reformed churches and to publish musical treatises in the vernacular. Agricola was self-taught, called to music “from the plough,” as his chosen surname suggests. He worked

  • Sohrab and Rustum (poem by Arnold)

    Sohrab and Rustum, epic poem in blank verse by Matthew Arnold, published in 1853 in his collection Poems. Among Arnold’s sources for this heroic romance set in ancient Persia were translations of an epic by the Persian poet Ferdowsī and Sir John Malcolm’s History of Persia (1815). The poem is an

  • Sōhyō (labour organization, Japan)

    Sōhyō, trade-union federation that was the largest in Japan. Sōhyō was founded in 1950 as a democratic trade-union movement in opposition to the communist leadership of its predecessor organization. It rapidly became the most powerful labour organization in postwar Japan and formed close ties with

  • SOI (Earth science)

    Australia: Climate: Monitoring the Southern Oscillation Index (SOI) is now considered essential to seasonal weather forecasting. The SOI is strongly negative when weak Pacific winds bring less moisture than usual to Australia. Prolonged negative phases are related to El Ni?o episodes in the South Pacific, and most of Australia’s…

  • Soi Dao, Mount (mountain, Thailand)

    Thailand: Relief: …2,614 feet (797 metres), and Mount Soi Dao, which attains a height of 5,471 feet (1,668 metres). The hills, reaching nearly to the sea, create a markedly indented coastline fringed with many islands. With their long stretches of sandy beach, such coastal towns as Chon Buri and Rayong and some…

  • soil (pedology)

    Soil, the biologically active, porous medium that has developed in the uppermost layer of Earth’s crust. Soil is one of the principal substrata of life on Earth, serving as a reservoir of water and nutrients, as a medium for the filtration and breakdown of injurious wastes, and as a participant in

  • soil binder (soil conservation)

    cordgrass: Some species are planted as soil binders to prevent erosion, and a few are considered invasive species in areas outside their native range. Prairie cordgrass (Spartina pectinata) and gulf cordgrass (S. spartinae) are the most widely distributed North American species.

  • soil centipede (arthropod)

    skeleton: Skeletomusculature of arthropods: …sclerites of burrowing centipedes (Geophilomorpha) enable them to change their shape in an earthwormlike manner while preserving a complete armour of surface sclerites at all times. The marginal zones of the sclerites bear cones of sclerotization that are set in the flexible cuticle, thus permitting flexure in any direction…

  • soil chemistry

    Soil chemistry, discipline embracing all chemical and mineralogical compounds and reactions occurring in soils and soil-forming processes. The goals of soil chemistry are: (1) to establish, through chemical analysis, compositional limits of natural soil types and optimal growth conditions for the

  • soil conservation

    lespedeza: …is also extremely useful in soil conservation. Some shrublike lespedeza species, such as the bicolour lespedeza (L. bicolor), are grown as ornamentals.

  • soil creep (slope movement)

    Creep, in geology, slow downslope movement of particles that occurs on every slope covered with loose, weathered material. Even soil covered with close-knit sod creeps downslope, as indicated by slow but persistent tilting of trees, poles, gravestones, and other objects set into the ground on

  • soil crust (geology)

    Duricrust, surface or near-surface of the Earth consisting of a hardened accumulation of silica (SiO2), alumina (Al2O3), and iron oxide (Fe2O3), in varying proportions. Admixtures of other substances commonly are present and duricrusts may be enriched with oxides of manganese or titanium within

  • soil erosion (geology)

    Erosion, removal of surface material from Earth’s crust, primarily soil and rock debris, and the transportation of the eroded materials by natural agencies (such as water or wind) from the point of removal. The broadest application of the term erosion embraces the general wearing down and molding

  • soil fertility

    agricultural sciences: Soil and water sciences: …century a general theory of soil fertility developed, embracing soil cultivation, the enrichment of soil with humus and nutrients, and the preparation of soil in accordance with crop demands. Water regulation, principally drainage and irrigation, is also included.

  • soil formation

    soil: Soil formation: As stated at the beginning of this article, soils evolve under the action of biological, climatic, geologic, and topographic influences. The evolution of soils and their properties is called soil formation, and pedologists have identified five fundamental soil formation processes that influence soil…

  • soil fumigant (chemistry)

    fumigant: Soil fumigants are sprayed or spread over an area to be cultivated and are worked into the soil to control disease-causing fungi, nematodes, and weeds.

  • soil group system (pedology)

    soil: Soil classification: Soil Taxonomy and the soil group system, published as the World Reference Base for Soil Resources, developed by the Food and Agriculture Organization (FAO) of the United Nations. Both of these systems are morphogenetic, in that they use structural properties as the basis of classification while also drawing on…

  • soil horizon (soil)

    Horizon, a distinct layer of soil, approximately parallel with the land surface, whose properties develop from the combined actions of living organisms and percolating water. Because these actions can vary in their effects with increasing depth, it is often the case that more than one horizon

  • soil layering (horticulture)

    arboriculture: In soil layering, the shoots, or lower branches of the parent plant, are bent to the ground and covered with moist soil of good quality. When roots have developed, which may require a year or more, the branch is severed from the parent and transplanted. In…

  • soil liquefaction (geology)

    Soil liquefaction, ground failure or loss of strength that causes otherwise solid soil to behave temporarily as a viscous liquid. The phenomenon occurs in water-saturated unconsolidated soils affected by seismic S waves (secondary waves), which cause ground vibrations during earthquakes. Although

  • soil loss tolerance (pedology)

    soil: Resistance to erosion: …the United States is the soil loss tolerance (T-value, or T-factor). This quantity is defined as the maximum annual rate of soil loss by erosion that will permit high soil productivity for an indefinite period of time. Operationally, the concept is interpreted as the maximum annual loss from the A…

  • soil management

    fruit farming: Soil management, irrigation, and fertilization: Two soil management practices (1) clean cultivation and chemical weed control or both and (2) permanent sod culture, illustrate contrasting purposes and effects. In clean cultivation or chemical weed control, the surface soil is stirred periodically throughout the…

  • soil mechanics

    Soil mechanics, the study of the physical properties and utilization of soils, especially used in planning foundations for structures and subgrades for highways. The first scientific study of soil mechanics was undertaken by French physicist Charles-Augustin de Coulomb, who published a theory of

  • soil moisture

    hydrologic sciences: Soil moisture: The soil provides a major reservoir for water within a catchment. Soil moisture levels rise when there is sufficient rainfall to exceed losses to evapotranspiration and drainage to streams and groundwater. They are depleted during the summer when evapotranspiration rates are high. Levels…

  • soil order system (pedology)

    soil: Soil classification: …in use today are the soil order system of the U.S. Soil Taxonomy and the soil group system, published as the World Reference Base for Soil Resources, developed by the Food and Agriculture Organization (FAO) of the United Nations. Both of these systems are morphogenetic, in that they use structural…

  • soil organism (biology)

    Soil organism, any organism inhabiting the soil during part or all of its life. Soil organisms, which range in size from microscopic cells that digest decaying organic material to small mammals that live primarily on other soil organisms, play an important role in maintaining fertility, structure,

  • soil profile

    soil: The soil profile: Soils differ widely in their properties because of geologic and climatic variation over distance and time. Even a simple property, such as the soil thickness, can range from a few centimetres to many metres, depending on the intensity and duration of…

  • soil respiration (pedology)

    soil: Carbon and nitrogen cycles: …CO2 gas, a process termed soil respiration. This amount of CO2 is more than 10 times larger than that currently produced from the burning of fossil fuels (coal and petroleum), but it is returned to the soil as organic matter by the production of biomass.

  • soil salinity (pedology)

    Australia: Agriculture, forestry, and fishing: The threat of soil salinization was reported later, especially in the irrigation districts where it was associated with overwatering and poor drainage.

  • soil science (geology)

    Pedology, scientific discipline concerned with all aspects of soils, including their physical and chemical properties, the role of organisms in soil production and in relation to soil character, the description and mapping of soil units, and the origin and formation of soils. Accordingly, pedology

  • soil seed bank (ecology)

    Soil seed bank, natural storage of seeds in the leaf litter, on the soil surface, or in the soil of many ecosystems, which serves as a repository for the production of subsequent generations of plants to enable their survival. The term soil seed bank can be used to describe the storage of seeds

  • soil structure (pedology)

    agricultural technology: Tilling: Soil is tilled to change its structure, to kill weeds, and to manage crop residues. Soil-structure modification is often necessary to facilitate the intake, storage, and transmission of water and to provide a good environment for seeds and roots. Elimination of weeds is important, because…

  • soil texture

    soil: Grain size and porosity: Soil texture refers to the relative proportions of sand, silt, and clay particle sizes, irrespective of chemical or mineralogical composition (see the figure). Sandy soils are called coarse-textured, and clay-rich soils are called fine-textured. Loam is a textural class representing about one-fifth clay, with sand…

  • soilless culture (horticulture)

    Hydroponics, the cultivation of plants in nutrient-enriched water, with or without the mechanical support of an inert medium such as sand or gravel. Plants have long been grown with their roots immersed in solutions of water and fertilizer for scientific studies of their nutrition. Early commercial

  • Soimonov, Fedor I. (Russian scientist)

    Caspian Sea: Study and exploration: …description of the sea by Fedor I. Soimonov, which contained the first navigational instructions, and an atlas of the sea were both published in 1731. Hydrographic exploration of the Caspian basin was continued by the Russian navy and was completed mainly in the second half of the 19th century. The…

  • Soini, Timo (Finnish politician)

    Finland: Domestic affairs: …president), the True Finn candidate, Timo Soini, and the similarly Euroskeptic Centre Party candidate, Paavo V?yrynen, finished fourth and third, respectively. In the runoff election held in February, the NCP’s pro-EU candidate, Sauli Niinist?, a former finance minister, became the first conservative to serve as Finland’s head of state in…

  • Soir, Le (Belgian magazine)

    Paul de Man: Life and career: …music critic of the newspaper Le Soir (“The Evening”), which had been seized by German authorities during the previous summer (it was soon referred to by Belgians as Le Soir [Volé]—“The [Stolen] Evening”). In March 1941 the newspaper published a set of articles attacking Jews, to which de Man contributed…

  • Soira, Mount (mountain, Eritrea)

    Eritrea: Relief: The highest point is Mount Soira, at 9,885 feet (3,013 metres). Geologically, the plateau consists of a foundation of crystalline rock (e.g., granite, gneiss, and mica schist) that is overlain by sedimentary rock (limestone and sandstone) and capped by basalt (rock of volcanic origin). The upper layers have been…

  • soiree (social event)

    Biedermeier style: …indispensable part of the popularized soiree. Soirees perpetuated the rising middle class’s cultural interests in books, writing, dance, and poetry readings—all subject matter for Biedermeier painting, which was either genre or historical and most often sentimentally treated. The most representative painters include Franz Krüger, Georg Friedrich Kersting, Julius Oldach, Carl…

  • Soirées de Médan, Les (French literature)

    French literature: Naturalism: …joint publication, in 1880, of Les Soirées de Médan, a volume of short stories by émile Zola, Guy de Maupassant, Joris-Karl Huysmans, Henry Céard, Léon Hennique, and Paul Alexis. The Naturalists purported to take a more scientifically analytic approach to the presentation of reality than had

  • Soissons (France)

    Soissons, town, Aisne département, Hauts-de-France région, northern France. The town is situated along the Aisne River in a rich agricultural valley surrounded by wooded hills. Soissons derives its name from the Suessiones, a Gaulish tribe that made the town its capital in the 1st century bce. A

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