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Rocks AND SOIL FORMATION

Rocks AND SOIL FORMATION

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Rocks AND SOIL FORMATION

  1. Prentice Hall EARTH SCIENCE Tarbuck Lutgens 
  2. Chapter 3 Rocks
  3. 3.1 The Rock Cycle  Rocks are any solid mass of mineral or mineral-like matter occurring naturally as part of our planet.  Types of Rocks 1. Igneous rock is formed by the crystallization of molten magma. Rocks
  4. 3.1 The Rock Cycle  Types of Rocks 2. Sedimentary rock is formed from the weathered products of preexisting rocks that have been transported, deposited, compacted, and cemented. 3. Metamorphic rock is formed by the alteration of pre-existing rock deep within Earth (but still in the solid state) by heat, pressure, and/or chemically active fluids. Rocks
  5. 3.1 The Rock Cycle  Shows the interrelationships among the three rock types (igneous, sedimentary, and metamorphic)  Magma is molten material that forms deep beneath the Earth’s surface.  Lava is magma that reaches the surface.  Weathering is a process in which rocks are broken down by water, air, and living things.  Sediment is weathered pieces of Earth elements. The Rock Cycle
  6. The Rock Cycle
  7. 3.1 The Rock Cycle  Processes driven by heat from the Earth’s interior are responsible for forming both igneous rock and metamorphic rock.  External processes produce sedimentary rocks.  Weathering and the movement of weathered materials are external processes powered by energy from the sun. Energy That Drives the Rock Cycle
  8. 3.2 Igneous Rocks 1. Intrusive igneous rocks are formed when magma hardens beneath Earth’s surface. 2. Extrusive igneous rocks are formed when lava hardens. Formation of Igneous Rocks
  9. 3. 2 Igneous Rocks 1. Texture  Igneous rocks can be classified based on their composition and texture. • Coarse-grained texture is caused by slow cooling resulting in larger crystals. • Fine-grained texture is caused by rapid cooling resulting in smaller, interconnected mineral grains. Classification of Igneous Rocks
  10. Course-Grained Igneous Texture
  11. Fine-Grained Igneous Texture
  12. 3.2 Igneous Rocks 1. Texture (continued) • Glassy texture is caused by very rapid cooling. • Porphyritic texture is caused by different rates of cooling resulting in varied sized minerals. 2. Composition • Granitic composition rocks are made mostly of light-colored quartz and feldspar. Classification of Igneous Rocks
  13. Obsidian Exhibits a Glassy Texture.
  14. Porphyritic Igneous Texture
  15. 3.2 Igneous Rocks 2. Composition (continued) • Basaltic composition rocks are made mostly of dark-colored silicate minerals and plagioclase feldspar. • Andesitic composition rocks are between granitic light-color minerals and basaltic composition dark-colored minerals. • Ultramafic composition rocks are made mostly from iron and magnesium-rich minerals. Classification of Igneous Rocks
  16. Basalt
  17. Classification of Igneous Rocks
  18. 3.3 Sedimentary Rocks • Erosion involves the weathering and the removal of rock. • Deposition occurs when an agent of erosion — water, wind, ice, or gravity — loses energy and drops sediments.  Weathering, Erosion, and Deposition Formation of Sedimentary Rocks
  19. 3.3 Sedimentary Rocks • Compaction is a process that squeezes, or compacts, sediments. • Cementation takes place when dissolved minerals are deposited in the tiny spaces among the sediments.  Compaction and Cementation Formation of Sedimentary Rocks
  20. 3.3 Sedimentary Rocks 1. Clastic sedimentary rocks are composed of weathered bits of rocks and minerals. • Classified by particle size  Two Main Groups — Shale (most abundant) • Common rocks include — Conglomerate — Sandstone Classification of Sedimentary Rocks
  21. Shale with Plant Fossils
  22. Conglomerate
  23. Fossiliferous Limestone
  24. Classification of Sedimentary Rocks
  25. 3. 3 Sedimentary Rocks  Features of sedimentary rocks are clues to how and where the rocks are formed Features of Some Sedimentary Rocks
  26. 3.4 Metamorphic Rocks  Metamorphism means “to change form.”  Conditions for formation are found a few kilometers below the Earth’s surface and extend into the upper mantle.  Most metamorphic changes occur at elevated temperatures and pressures. Formation of Metamorphic Rocks
  27. Origin of Pressure in Metamorphism
  28. Classification of Metamorphic Rocks
  29. Gneiss Typically Displays a Banded Appearance
  30. Marble — A Nonfoliated Metamorphic Rock

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Rock and Soil Mechanics, Volume 48

Rock and Soil Mechanics, Volume 48 — 1st EditionShopping CartopenUserAccount

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1st Edition — January 1, 1989

Authors: W. Derski, R. Izbicki, I. Kisiel, Z. Mróz

eBook ISBN: 9780444596987

9 7 8 — 0 — 4 4 4 — 5 9 6 9 8 — 7

Although theoretical in character, this book provides a useful source of information for those dealing with practical problems relating to rock and soil mechanics — a discipline… Read more

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Although theoretical in character, this book provides a useful source of information for those dealing with practical problems relating to rock and soil mechanics — a discipline which, in the view of the authors, attempts to apply the theory of continuum to the mechanical investigation of rock and soil media. The book is in two separate parts. The first part, embodying the first three chapters, is devoted to a description of the media of interest. Chapter 1 introduces the main argument and discusses the essence of the discipline and its links with other branches of science which are concerned, on the one hand, with technical mechanics and, on the other, with the properties, origins, and formation of rock and soil strata under natural field conditions. Chapter 2 describes mechanical models of bodies useful for the purpose of the discourse and defines the concept of the limit shear resistance of soils and rocks. Chapter 3 gives the actual properties of soils and rocks determined from experiments in laboratories and in situ. Several tests used in geotechnical engineering are described and interconnections between the physical state of rocks and soils and their rheological parameters are considered.The second part of the book considers the applications of various theories which were either first developed for descriptive purposes in continuum mechanics and then adopted in soil and rock mechanics, or were specially developed for the latter discipline. Chapter 4 discusses the application of the theory of linear viscoelasticity in solving problems of stable behaviour of rocks and soils. Chapter 5 covers the use of the groundwater flow theory as applied to several problems connected with water movement in an undeformable soil or rock skeleton. Chapter 6 is a natural expansion of the arguments put forward in the previous chapter. Here the movement of water is regarded as the cause of deformation of the rock or soil skeleton and the consolidation theory developed on this basis is presented in a novel formulation. Some new engineering solutions are also reported. The seventh chapter is devoted to the limit state theory as applied to the study of the mechanical behaviour of soils and rocks. It presents some new solutions and methods which include both static and kinematic aspects of the problem, and some original effective methods for investigating media of limited cohesion. The final chapter gives a systematic account of the mechanics of highly dispersed soils, commonly called clays.

What distinguishes soil from rock — basic properties briefly (grade 8, geography)

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Updated March 4, 2023

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Updated March 4, 2023

Rocks form the earth’s crust. They are found on its surface and at depths of up to 40–70 km. Rocks differ in age, composition, and layer thickness. The top layer of rocks is affected by external forces. Here, on the surface of the earth, soils are formed. This is a special natural body, which is characterized by its structure and properties.

What is rock

Substances of the earth’s crust — rocks. They are made up of minerals. The composition of the rock may include one mineral or several.

There are a lot of rocks. In the bark, they lie in layers. Rocks located on the surface of the earth affect the formation of soil.

Rice. 1. Rocks.

What is soil

The top fertile layer of the earth is called soil. It develops very slowly. Hundreds of years pass, during which soils form on rocks. During this time, plants appear on the earth’s surface. The top layer is inhabited by living organisms.

Over time, living organisms die off. Dead remains are processed by worms, fungi and microorganisms. This process is called decomposition or decay. As a result, humus or humus is formed, which accumulates over time.

Humus is the main component of the soil. Fertility depends on it. The greater the layer of humus, the higher the fertility of the soil.

Humus contains nutrients: nitrogen, phosphorus, potassium. They are in a form available to plants.

In order for soil to form, a layer of humus must accumulate in a volume that can affect the underlying layers. In this case, we talk about the formation of the soil.

Any type of it has its own profile. It is noticeable on a vertical section consisting of three layers or soil horizons:

  • accumulation of humus;
  • washout horizon;
  • washout horizon.

On soil profiles, the humus accumulation horizon has a dark color. The second layer is lighter in color. From it, mineral and organic substances are washed out with water and carried deeper. The next horizon has a darker color. Here the washed substances are deposited. Below lies the parent rock.

Rice. 2. Soil profile.

Chernozems are the most fertile soils. The layer of humus in these types of soil reaches a meter or more.

What distinguishes soil from rock

There is one main difference between rocks and soil. This is fertility, the main property of the soil. It depends on the amount of accumulated humus.

The formed soils are characterized by a soil profile where three horizons are clearly traced.

Rocks are not fertile because they do not contain humus. There are no horizons in the rock layers. They are homogeneous.

Soil formation is impossible without rocks. Plants and animals need a solid support on which to settle. Rocks are the beginning of soil formation.

Between the particles of soil and rocks there is air, water, living organisms can settle. As soon as the accumulation of humus begins, the formation of the soil begins.

Soil, as a special natural body, consists of components: rocks, humus, minerals, living organisms, water, air.

Rice. 3. The composition of the soil.

Briefly about soils, their diversity and difference from rocks, you can prepare a report for a geography lesson in grade 8.

What have we learned?

Soils differ from rocks in the presence of humus. Fertility depends on the amount of humus. Soils are formed on rocks.

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Rocks

Rocks are natural mineral aggregates of a certain composition and structure, formed as a result of geological processes and occurring in the earth’s crust in the form of independent bodies. [ …]

and others), in solutions — in the form of an ion (5042). in the gaseous phase in the form of hydrogen sulfide (H) or sulfur dioxide (S02). In some organisms, sulfur accumulates in its pure form (S), and when they die, deposits of native sulfur are formed on the bottom of the seas. In the marine environment, the sulfate ion ranks second in content after chlorine and is the main available form of sulfur, which is restored by autotrophs and is included in composition of amino acids.[ …]

Sedimentary rocks are predominantly surface formations that have arisen during the destruction and redeposition of other — previously formed — rocks (crushed stone, gravel, sand, pebbles, sandstones, clays).[ …]

Outcrops of dense rocks ( 0.9 million ha), as well as eternal snow and glaciers (9.0 million ha) are non-soil formations.[ …]

Their chemical composition is related to the size of rock fragments. So, sands of water-glacial and alluvial origin are silicon oxide. Silts and clays are fragments of feldspars, and in terms of chemical composition they are aluminosilicates of various metals: potassium, sodium, calcium, magnesium, iron, etc. Therefore, a higher trophicity is understandable compared to sedimentary sands, where sands contain clay particles in various proportions.[ …]

Igneous (igneous) rocks. They are formed during the cooling of molten magmas rising from the depths of the Earth to its surface. There are deep rocks, if the magma has frozen at a depth, and erupted, if the cooling has already occurred on the surface. Igneous rocks consist mainly of silicates and aluminosilicates, the most important components of which are silica (SiO2) and alumina (A1203). Further classification is carried out primarily depending on the content of silica in the rock — silicic anhydride (Table 7.11).[ …]

Among the great variety of mountain soils, the following main types are distinguished (% of the total soil area of ​​the USSR): mountain tundra — 7. 6; mountain meadow — 0.7; mountain-meadow-steppe — 0.5; mountain podzolic and permafrost-taiga — 15.3; mountain permafrost-taiga carbonate — 1.4; mountain sod subarctic — 0.4; mountain gray forest — 0.7; mountain sod-carbonate — 0.1; mountain brown forest — 0.9; mountain zheltozems — 0.1; mountain brown — 0.3; mountain chernozems — 0.5; mountain chestnut — 0.6; mountain gray soils — 0.2; alpine desert — 0.2; rock outcrops — 0.1.[ …]

The soil consists of broken rocks and organic matter (decomposed plants). But the first plants on earth had to begin their development on rocks destroyed by water and air. They had to settle on rocks, minerals, destroying them with their roots. After the death of these plants, the destruction continued with humus, which is formed from their remains. Thus the soil was created.[ …]

The solid phase of soils and soil-forming rocks consists of particles of various sizes, which are called mechanical elements. By origin, mineral, organic and organo-mineral particles are distinguished. They are fragments of rocks, individual minerals (primary and secondary), humic substances, products of the interaction of organic and mineral substances.[ …]

Soil is a layer of matter lying on top of the rocks of the earth’s crust. The soil is formed as a result of many factors, the main of which are climate, parent rock (geological conditions), topography (relief), living organisms and time.[ …]

Thus, the geological cycle and circulation of rocks consists of: 1 ) weathering, 2) formation of sediments, 3) formation of sedimentary rocks, 4) metamorphism, 5) magmatization. The exit to the daytime surface of magma and the formation of igneous rocks repeats the whole cycle from the beginning. The full cycle can be interrupted at various stages (3 or 4) if, as a result of tectonic uplifts and denudation, rocks come to the surface and undergo repeated weathering.[ …]

In accumulative landscapes, the surface of bedrock is covered with a thick layer of loose deposits. Loose deposits formed over the past 1.5 million years are called Quaternary or Anthropogenic, since their formation coincides in time with the appearance of man on Earth. On the accumulative plains, the thickness of the Quaternary deposits is measured in meters and tens of meters, they serve as a substrate for the rooting of forest plants, and the underlying bedrock does not have a noticeable effect on the flora and fauna.[ …]

Solifluction — a slow flow of thawed soils, soils or rocks on gentle slopes of the relief under the influence of gravity, moisture migration and other factors.[ …]

A geological phenomenon associated with the dissolution of rocks (limestone, dolomite, gypsum) , rock salt), the formation of underground voids (caverns, caverns, etc.) and accompanied by a failure of the earth’s surface, was called karst. Massifs of rocks in which karst develops are called karst. Karst is widespread in the world, including in Russia, in particular, in Bashkiria, in the central part of the Russian Plain, in the Angara region, in the North Caucasus and in many other places where there are soluble rocks. [ …]

The practical implementation of this idea is rather complicated. Not all rocks are collectors, i.e. rocks capable of containing oil, water and gases. In practice, sewage injection is allowed to a depth of at least 600 and, in this case, a number of other hydrogeological conditions are required. Such conditions may not be near an oil refinery or a chemical plant, then this method of water disposal will be impracticable.[ …]

it may take many years. Therefore, preventive measures are the main ones in environmental protection measures. Groundwater pollution can be prevented in a variety of ways. To this end, wastewater treatment methods are being improved to prevent the ingress of polluted effluents into groundwater. They introduce production with drainless technology, carefully screen the bowls of pools with industrial effluents, reduce hazardous gas and smoke emissions at enterprises, regulate the use of pesticides and fertilizers in agricultural work, etc. e.[ . ..]

Crushability is a generalizing parameter of many mechanical properties of rocks (elastic, strength, plastic, etc.) and expresses the energy intensity of the rock crushing process.[ …] drainage network. Sharp angular bends of the channel are typical not only for tributaries, but also for the main channel. The nature and direction of angularity can also reflect the specifics of rock types. For example, sandstones develop a parallel fracture pattern, while limestones form fractures that intersect at an acute angle.[ …]

As can be seen from the table. 1.1 and 1.2, the most advantageous type of deformation for the destruction of rocks is tension, but for constructive reasons, in modern practice of disintegration, the main destructive effect is crushing. [ …]

When fresh water is injected, it interacts with oil, gas, bound water and rock rock in the reservoir. There are reactions of ion exchange, mutual dilution and chemical transformation (transformation). Due to the leaching of rocks, water is saturated with sulfates, carbonates, silicon. As a result, salts are deposited on downhole and oilfield equipment.[ …]

Thermokarst — uneven subsidence or collapse of the soil and underlying rock layers due to the melting of ice inclusions from them. At the same time, depressions are formed on the day surface, in which water accumulates, which contributes to deeper thawing of the frozen ground. In subsequent years, the drawdown increases, and with it the amount of water in the depressions; small thermokarst reservoirs are formed. The warming effect of water and the developing slope processes lead to the destruction of the banks of water bodies and their confluence occurs.[ …]

Ground waters lie on the impervious horizon of soils of loose sediments or dense rocks. Clays, crystalline schists, granites, non-fractured limestones, marls, etc. are relatively impermeable water-resistant rocks. In soils, illuvial horizons B can become compacted and play the role of an aquiclude. The accumulation of iron oxides in soils leads to the formation of impermeable ortstein and ortzand horizons. In areas with permafrost, the role of an aquiclude can be played by frozen rocks, over which freezing or non-freezing permafrost groundwater occurs. When close to the surface, the aquiclude creates temporary or permanent excessive waterlogging of the PTC, which leads to the formation of swamps and swampy forests.[ …]

Diagenesis is the process of transformation of loose sediments at the bottom of water basins into sedimentary rocks in the conditions of the upper zone of the earth’s crust.[ …]

The diversity of tracts is determined by the geological structure and lithological composition of rocks in which denudation forms of mountain relief have been developed. Therefore, the geological structure and lithological composition of rocks is the basis for the classification of tracts of mountains.[ …]

Geological structure is the sequence and location of rock layers in the earth’s crust. The lithological composition of rock layers is a combination of various minerals, fragments and granules that compose them. [ …]

Drilling animals — marine invertebrates, making passages or depressions in wood, in rocks (limestone), etc. Thus, penetration into a solid substrate occurs by mechanical (drilling) or chemical (dissolution with acids) effects. Woodworms include bivalve molluscs (shipworm), isopods, amphipods and pogonophores. Some gastropods drill holes in the shells of other mollusks by secreting salivary glands containing 2-4% sulfuric acid and eat them. This property is possessed by drilling sponges, some species of sea urchins, polychaete worms, etc. Many drilling animals destroy the underwater parts of wooden ships, piles and other underwater structures.[ …]

The runoff of rain and melt water occurs both on the earth’s surface (deluvial water) and in the thickness of rocks and sediments (underground runoff). The ratio of the runoff to the amount of precipitation that fell on the catchment area, expressed as a percentage, is called the runoff coefficient.[ …]

Aerial gamma survey — the study of the characteristics of the energy spectrum of natural gamma radiation of rocks from aircraft using airborne gamma spectrometers. It is used in combination with other methods for geological and radio-geochemical mapping, as well as for searching for accumulations of radioactive elements and deposits of a number of other minerals.[ …]

Glacial or moraine deposits, briefly referred to as moraine, are accumulations of unsorted rock fragments — boulders, pebbles, gravel, sands, silts and clays, carried and deposited by a glacier. Clay varieties are characterized by greater compaction and low porosity, sometimes schistosity.[ …]

Natural chemical compounds of the elements of the earth’s crust are called minerals. Numerous types of rocks are composed of them. The main groups of rocks are igneous, sedimentary and metamorphic.[ …]

The main factors influencing the change in hydrological conditions during quarrying are the exposure of rock masses by mine workings, the opening of aquifers, the preliminary drainage of the deposit, quarry drainage, artificial change in surface runoff, the installation of hydraulic dumps, sludge storages, the discharge of quarry and industrial waters. Open pit mining leads to a decrease in the level of groundwater. Depression funnels around deep quarries that undercut all aquifers extend for tens of kilometers.[ …]

Lithosphere (Greek «cast» — stone) — the stone shell of the Earth, including the earth’s crust with a thickness (thickness) from b (under the oceans) to 80 km (mountain systems) (Fig. 6.1). The earth’s crust is composed of rocks. The proportion of various rocks in the earth’s crust is not the same — more than 70% are basalts, granites and other igneous rocks, about 17% are rocks transformed by pressure and high temperature, and only a little more than 12% are sedimentary (Table 6.1). ..]

In Yakutia, in the Bodaibo gold mining region, in the pre-October period, it was considered unprofitable to develop areas with a gold content of less than 8 g in one ton of rock due to the high cost of the forest necessary for mining, caused by its depletion partly by fires, partly by logging: about 1/3 the cost of mined gold had to be spent on the extraction of forest materials (M. I. Sumgin and B.N. Demchinsky).[ …]

Terrain types depend on absolute heights, that is, heights above sea level. Absolute heights are associated with: the genesis of landforms, their age, history of development (and in connection with this — the lithological composition of rocks and sediments), dissection, permafrost, a set of meso- and macroforms, water balance, swampiness and lakes and other parameters, in In general, the structure of the NTC and the ecological regime of the lands.[ …]

As a result of the transformation and movement of substances in the soil, different genetic horizons are distinguished. The landscape analysis of soils and its horizons reveals signs of the lithological composition of the rocks of the substrate on which it is formed, relic signs — historical signs of its formation and ecological signs — signs of the ecological regimes of lands.[ …]

THE SECOND BASIC PRINCIPLE OF THE FUNCTIONING OF ECOSYSTEMS — Ecosystems exist due to solar energy, which is available in excess, inexhaustible and does not pollute the environment. d WEATHERING — the gradual destruction of rocks into smaller and smaller parts under the influence of physical, chemical and biological factors.[ …]

The relief of the Earth is a set of forms of the earth’s surface. Each landform is a three-dimensional natural body that occupies a certain volume of the earth’s crust. Therefore, just like the earth’s crust as a whole, the relief form is a natural unity of the geological structure, lithological composition of rocks and surface shape.[ …]

On slopes subject to shedding, vegetation is often completely absent or fragmentary, forming on relatively weakly mobile parts of the slopes. The treeless sides of the river valleys washed away by the river, which are called ravines, are well known. In the upper part of the ravine, rocks of various horizons come to the surface; this is a natural section of the earth’s crust. The natural outcrop of rocks is the separation wall. The word Yar is associated with the name of many settlements in Russia (Krasnoyarsk, Beloyarsk, Bely Yar, Veseloyarsk, Krasny Yar, Sytny Yar, Yar, Yartsevo, Yaroslavl). [ …]

Ore is a mineral raw material containing enough metals to be extracted and sold for a profit. The observed trend is that the average iron content in raw ore over the past 30 years has decreased from 51 to 35%, and the consumption of raw ore has increased from 1.2 to 2.0 tons for the production of 1 ton of marketable ore [1]. A rock is a naturally formed solid substance containing one or more minerals.[ …]

In the Arkhangelsk forests within the Shelekovsky forestry enterprise, pure pine forests grow on glacial sands, and on loamy podzolic soils — mixed stands of pine, larch Siberian spruce. Here there are loamy podzolic soils of two kinds. Some soils do not contain coal salts and are underlain by boulders. On these soils grow stands of lower productivity: stands 4S4L2E in 190 years yields 270 m3 of total stock per 1 ha. Other podzolic loams were formed on calcareous parent rock with coal salts close to the day surface (at a depth of 0.3-0.8 m). Here, a stand of similar composition — 4SZLZE at an age younger than in the first case, at 156 years old, gives a much larger reserve — 510 ml per 1 ha. If, however, we take into account that part of the forest stand was cut down during selective felling, then the total stock will have to be increased to 650-700 m3 per 1 ha.[ …]

The second cycle is also not completely closed, because the oceans are constantly depositing and storing carbon in bottom sediments as carbonates. According to some estimates, the rate of carbon accumulation in this form is 0.1 Gt C/year. From Table. 2.1 shows that the waters of the oceans contain about 1000 Gg of organic carbon. This amount exceeds the carbon stock in the biomass of the continents and is close to its content in the soil humus. Organic matter dispersed throughout the oceanic waters is sometimes referred to as aquatic humus. It is important that, like soil humus and dispersed organic matter of rocks (kerogen), it is inaccessible for assimilation by microorganisms. True, the reasons for this inaccessibility are different. Geopolymers — components of soil humus and kerogen — are resistant to biochemical degradation due to their chemical structure (see Section 1. 4). On the contrary, water humus is formed by easily degradable compounds — carbohydrates, amino acids and fatty acids. However, their concentrations in sea water are below the concentration corresponding to half the maximum growth rate of microorganisms (about 10 mg/l). This makes it unprofitable for microorganisms to use aquatic humus, and it becomes a huge reservoir of carbon (G. A. Zavarzin, 1984).[ …]

Due to the highest activity of biogeochemical processes and the colossal volumes and scales of the turnover of substances, biologically significant chemical elements are in constant cyclic motion. According to some estimates, if we assume that the biosphere has existed for at least 3.5-4 billion years, then all the water of the World Ocean has passed through the biogeochemical cycle at least 300 times, and the free oxygen of the atmosphere — at least 1 million times. The cycle of carbon occurs in 8 years, nitrogen in 110 years, oxygen in 2500 years. The main mass of carbon concentrated in the carbonate deposits of the ocean floor (1. 3 x 1016 t), other crystalline rocks (1 x 1016 t), coal and oil (0.34 x 1016 t), participates in a large cycle. Carbon contained in plant (5 x 10mt) and animal tissues (5 x 109t), participates in a small circulation (biogeochemical cycle).[ …]

In general, the functional interdependence of the elements of the biosphere forms it as a global self-regulating ecosystem that ensures the circulation of substances at this level and guides (including «filtering» the flow of energy , as well as using (including transforming) the flow of information. A special position in this planetary system is occupied by various living organisms, which V.I. Vernadsky called «living matter». He ranked plants, animals and microorganisms among it. «He attributed formations of organic origin created by living organisms and consisting of plant and animal remains — coal, peat, soil humus, oil, chalk, limestone, etc.; to «inert matter» — rocks of inorganic origin; to «bio-inert matter» — products of decay and processing of rocks by living organisms. [ …]

Studies have shown that at a radiation dose of 1000 rad a person dies, at a dose of 200 to 700’rad, death is observed in 10 and 90% of cases, respectively; in the case of a dose of up to 100 rad, a person survives, but the likelihood of cancer is high. The safe dose of ionizing radiation should not exceed twice the average dose of radiation to which a person is exposed under natural conditions. Based on this, the permissible doses of single exposure (10 rem) and exposure of the population under normal conditions per year (0.5 rem) were established [182 . In addition, it is necessary to take into account the doses that a person receives from artificial sources of radiation. So, radiation exposure during fluoroscopy of the stomach is 30 rem (local), and when watching a hockey match on TV — 100 microrem.[ …]

Underbald spruce forests are distributed near the altitudinal limits of the distribution of Ayan spruce. Usually they are represented by a narrow strip of uneven width. The altitude levels that they occupy depend on the position of the upper forest boundary, determined by the height and massiveness of the mountains, the degree of influence of the sea, and a number of other factors. The lowest located plant groups, which have a physiognomic appearance and structure of forest stands, which are characteristic of the subalpine zone, are located on the islands and near the sea coast. The underbald forests are characterized by a low density of stands and often a park appearance, low thickness and high stony soils, usually well-developed undergrowth and a shrub-grass layer. Phytocoenotic resistance of spruce is somewhat weakened. As the absolute height in the forest stand increases, as a rule, the participation of stone birch increases, the thinness of the tree canopy increases, and the participation of fir decreases (starting from the Middle Sikhote-Alin and to the north). The habitats of the underbald spruce forests are characterized by high air humidity and increased flowing moisture, which is created due to the long-term preservation of seasonal soil frost.

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