alteration

Earth, also known as Terra, and Tellus mostly in the 19th century, is the third-closest planet to the Sun. It is the largest of the solar system's terrestrial planets, and the only planetary body that modern science confirms as harboring life. Scientific evidence indicates that the planet formed around 4.57 billion (4.57×109) years ago, and shortly thereafter (4.533 billion years ago) acquired its single natural satellite, the Moon. Earth - Lexicography. Its astronomical symbol con ...

Including:

• Earth - Lexicography
• Earth - Physical characteristics
• Earth - Earth in the solar system
• Earth - The Moon
• Earth - Geography
• Earth - Environment and Ecosystem
• Earth - Climate
• Earth - Terrain
• Earth - Natural resources
• Earth - Land use
• Earth - Natural and environmental hazards
• Earth - Human geography
• Earth - Descriptions of Earth

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The soil represents the surface layer, of the earth's crust, resulting from the transformation of the bare rock, enriched by organic input. At the beginning of a soil formation, only the bare rock outcrops. It is gradually colonized by pioneer species (lichens and mosses), then herbaceous vegetation, shrubs and finally forest. In parallel a first humus-bearing horizon is formed (the A horizon), followed by some mineral horizons (B horizons). Each successive stage is characterized by a certain ...

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Soils retrogression and degradation, Soils retrogression and degradation - Soil evolution cycle, Soils retrogression and degradation - Ecological factors influencing soil formation, Soils retrogression and degradation - Biorhexistasy theory, Soils retrogression and degradation - Perturbations of the balance of a soil, Soils retrogression and degradation - Influence of human activity, Soils retrogression and degradation - Consequences of soil regression and degradation, Soils retrogression and degradation - Soil enhancement and rebuilding

Read more here: » Soils retrogression and degradation: Encyclopedia II - Soils retrogression and degradation - Soil evolution cycle

It takes the Earth 23 hours, 56 minutes and 4.091 seconds (1 sidereal day) to rotate around the axis connecting the north pole and the south pole. From Earth the main apparent motion of celestial bodies in the sky (except meteors which are within the atmosphere and low-orbiting satellites) is the movement to the west at a rate of 15 °/h = 15'/min, i.e., a Sun or Moon diameter every two minutes. Earth orbits the Sun every 365.2564 mean solar days (1 sidereal year). From Earth, this gives an apparent movement of the Sun with respect to the stars at a rate of about 1 °/day, i.e ...

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Earth, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Earth in the solar system

It takes the Earth 23 hours, 56 minutes and 4.091 seconds (1 sidereal day) to rotate around the axis connecting the north pole and the south pole. From Earth the main apparent motion of celestial bodies in the sky (except meteors which are within the atmosphere and low-orbiting satellites) is the movement to the west at a rate of 15 °/h = 15'/min, i.e., a Sun or Moon diameter every two minutes. Earth orbits the Sun every 365.2564 mean solar days (1 sidereal year). From Earth, this gives an apparent movement of the Sun with respect to the stars at a rate of ca. 1 °/day, i. ...

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Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Earth in the solar system

Earth is the only place in the universe where life is absolutely known to exist, and some scientists believe that biospheres might be rare. The planet's lifeforms are sometimes said to form a "biosphere". This biosphere is generally believed to have begun evolving about 3.5 billion (3.5×109) years ago. The biosphere is divided into a number of biomes, inhabited by broadly similar flora and fauna. On land, biomes are separated primarily by latitude. Terrestrial biomes lying within the Arctic and Antarctic Circles are re ...

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Earth, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Environment and Ecosystem

Earth has often been personified as a deity, in particular a goddess (see Gaia and Mother Earth). The Chinese Earth goddess Hu-Tu is similar to Gaia, the deification of the Earth. As the patroness of fertility, her element is Earth. In Norse mythology, the Earth goddess Jord was the mother of Thor and the daughter of Annar. Since Earth is rather large, it is not immediately obvious to the naked eye viewing from the surface that it is an oblate spheroid, bulging slightly at the equator and slightly flattened at the poles. In the ...

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Earth, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Descriptions of Earth

The destruction of the vegetation implies the destruction of evoluted soils, or a regressive evolution. Cycles of succession-regression of soils follow one another within short intervals of time (human actions) or long intervals of time (climate variations). The climate role in the deterioration of the rocks and the formation of soils lead to the formulation of the theory of the biorhexistasy (Erhart). In wet climate, the conditions are favorable to the deterioration of the rocks (mostly chemically), the development of th ...

See also:

Soils retrogression and degradation, Soils retrogression and degradation - Soil evolution cycle, Soils retrogression and degradation - Ecological factors influencing soil formation, Soils retrogression and degradation - Biorhexistasy theory, Soils retrogression and degradation - Perturbations of the balance of a soil, Soils retrogression and degradation - Influence of human activity, Soils retrogression and degradation - Consequences of soil regression and degradation, Soils retrogression and degradation - Soil enhancement and rebuilding

Read more here: » Soils retrogression and degradation: Encyclopedia II - Soils retrogression and degradation - Biorhexistasy theory

Erosion is the main factor for soil degradation and is due to several mechanisms: water erosion, wind erosion, chemical degradation and physical degradation. Erosion is strongly related to human activity. For example, roads which increase impermeable surfaces lead to streaming and ground loss. Agriculture also accelerates soil erosion (increase of field size, correlated to hedges and ditches removal). Meadows are in regression to the profit of plowed lands. Spring cultures (sunflower, corn, beet) surfaces are increasing and leave the ...

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Soils retrogression and degradation, Soils retrogression and degradation - Soil evolution cycle, Soils retrogression and degradation - Ecological factors influencing soil formation, Soils retrogression and degradation - Biorhexistasy theory, Soils retrogression and degradation - Perturbations of the balance of a soil, Soils retrogression and degradation - Influence of human activity, Soils retrogression and degradation - Consequences of soil regression and degradation, Soils retrogression and degradation - Soil enhancement and rebuilding

Read more here: » Soils retrogression and degradation: Encyclopedia II - Soils retrogression and degradation - Influence of human activity

The Earth consists of several atmospheric, hydrologic, and mainly geologic layers. Its components are the atmosphere, the hydrosphere, the crust, the mantle, and its core. The biosphere is a tiny layer in this composition and is usually not considered part of the physical layers of the Earth. The geologic component layers of the Earth are located at the following depths below surface: 0 to 60 km - Lithosphere (locally varies between 5 and 200 km) 0 to 35 km - Crust (locally varies between 5 and 70 km) 35 ...

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Earth, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Physical characteristics

Map references: Time Zones, Coordinates. Biggest geographic subdivision Continents, Oceans Area: Total: 510.073 million km2 land: 148.94 million km2 Water: 361.132 million km2 Note: 70.8 % of the world's surface is covered by water, 29.2 % is exposed land Land boundaries: the land boundaries in the world total ...

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Earth, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Geography

When the state of balance, characterized by the ecosystem climax is reached, it tends to be maintained stable in the course of time. The vegetation installed on the ground provides the humus and ensures the ascending circulation of the matters. It protects the ground from erosion by playing the role of barrier (for example, protection from water and wind). Plants can also reduce erosion by binding the particles of the ground to their roots. A disturbance of climax will cause retrogression, but, if given the opportunity, nature will ma ...

See also:

Soils retrogression and degradation, Soils retrogression and degradation - Soil evolution cycle, Soils retrogression and degradation - Ecological factors influencing soil formation, Soils retrogression and degradation - Biorhexistasy theory, Soils retrogression and degradation - Perturbations of the balance of a soil, Soils retrogression and degradation - Influence of human activity, Soils retrogression and degradation - Consequences of soil regression and degradation, Soils retrogression and degradation - Soil enhancement and rebuilding

Read more here: » Soils retrogression and degradation: Encyclopedia II - Soils retrogression and degradation - Perturbations of the balance of a soil

Earth is the only place in the universe where life is known to exist. The planet's lifeforms are sometimes said to form a "biosphere". This biosphere is generally believed to have begun evolving about 3.5 billion (3.5×109) years ago. The biosphere is divided into a number of biomes, inhabited by broadly similar flora and fauna. On land, biomes are separated primarily by latitude. Terrestrial biomes lying within the Arctic and Antarctic Circles are relatively barren of plant and animal life, while most of the more populous biomes ...

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Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Environment and Ecosystem

See also: Geology The Earth consists of several atmospheric, hydrologic, and mainly geologic layers. Its components are the atmosphere, the hydrosphere, the crust, the mantle, and its core. The biosphere is a tiny layer in this composition and is usually not considered part of the physical layers of the Earth. The geologic component layers of the Earth are located at the following depths below surface: 0 to 60 km - Lithosphere (locally varies between 5 and 200 km) 0 to 35 km - Crust (locally varies between ...

See also:

Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Physical characteristics

Its astronomical symbol consists of a circled cross, representing a meridian and the equator; a variant puts the cross atop the circle (Unicode: ⊕ or ♁). Besides words derived from Terra, such as terrestrial, terms that refer to the Earth include tellur- (telluric, tellurian, from the Roman goddess Tellūs) and geo- (geocentric, geo ...

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Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Lexicography

Earth has often been personified as a deity, in particular a goddess (see Gaia and Mother Earth). The Chinese earth goddess Hu-Tu is similar to Gaia, the deification of the earth. As the patroness of fertility, her element is earth. In Norse mythology, the earth goddess Jord was the mother of Thor and the daughter of Annar. Since Earth is rather large, it is not immediately obvious to the naked eye viewing from the surface that it is an oblate spheroid, bulging slightly at the equator and slightly flattened at the poles. In the ...

See also:

Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Descriptions of Earth

Map references: Time Zones, Coordinates. Biggest geographic subdivision Continents, Oceans Area: Total: 510.073 million km2 land: 148.94 million km2 Water: 361.132 million km2 Note: 70.8 % of the world's surface is covered by water, 29.2 % is exposed land Land boundaries: the land boundaries in the world total 251,480 km (not counting shared boundaries twice) Coas ...

See also:

Earth, Earth - Lexicography, Earth - Physical characteristics, Earth - Earth in the solar system, Earth - The Moon, Earth - Geography, Earth - Environment and Ecosystem, Earth - Climate, Earth - Terrain, Earth - Natural resources, Earth - Land use, Earth - Natural and environmental hazards, Earth - Human geography, Earth - Descriptions of Earth

Read more here: » Earth: Encyclopedia II - Earth - Geography