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1. Atmosphere as a part of biosphere

An atmosphere - is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low. Some planets consist mainly of various gases, but only their outer layer is their atmosphere.

The term stellar atmosphere describes the outer region of a star, and typically includes the portion starting from the opaque photosphere outwards. Relatively low-temperature stars may form compound molecules in their outer atmosphere. Earth's atmosphere, which contains oxygen used by most organisms for respiration and carbon dioxide used by plants, algae and cyanobacteria for photosynthesis, also protects living organisms from genetic damage by solar ultraviolet radiation. Its current composition is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms.

The atmospheric composition on Earth is largely governed by the by-products of the very life that it sustains. Earth's atmosphere contains roughly (by molar content/volume) 78.08% nitrogen, 20.95% oxygen, a variable amount (average around 1.247%) water vapor, 0.93% argon, 0.038% carbon dioxide, and traces of hydrogen, helium, and other "noble" gases.

The Earth's atmosphere consists, from the ground up, of the troposphere (which includes the planetary boundary layer or peplosphere as lowest layer), stratosphere (which includes the ozone layer), mesosphere, thermosphere (which contains the ionosphere), exosphere and also the magnetosphere. Each of the layers has a different lapse rate, defining the rate of change in temperature with height.

2. Protection of water pool from pollution. Normalization of water consumption at the enterprises

Oil refining and chemical industries are related to water capacious industries and they concede on water use only to power, metallurgy, the chemical industry and public services. The most part of water is used to cool and to condensate, and the products is also used as solvent or reagent as steam. Having passed this or that cycle, water is undergoes various changes, or it is irrevocably lost. Sewage contain both soluble, insoluble organic and inorganic substances, including toxic ones.

Oil and oil products are related to number of the most widespread and dangerous pollutant substances. In addition to hydrocarbons the sewage contains O-, S- and N-containing compounds.

The main principles of sewage treatment is necessity of the maximal reduction of sewage amount and decrease of impurities contents in them; a possibility to extract the valuable components from sewage and their subsequent reclamation; a reuse of sewage in technological processes and in the systems of circulating water supply.

Normalization of the harmful substances, disposal with sewage.

Before disposal in a pond sewage should be cleaned up to the highest degree because under effect of natural factors the secondary products of decomposition may be formed, negatively influencing quality of water.

To carry out process it is necessary, firstly, after sewage disposal, the presence in the pond of the soluble oxygen. Chemical or bacterial oxidation of the organic substances contained in the sewage, results in decrease in concentration of oxygen, dissolved in water. (1 liter of H₂O contains 8-9 sm³ of O₂. Organic substances interacting with dissolved O₂ are oxidized to СО₂ and Н₂О. Therefore, the parameter was entered allowing estimating the total quantity of pollution in water according to absorption of О₂. Such parameter is biochemical demand of oxygen (BOD). BOD is equaled to quantity of O₂. Depending on time there are BOD₅ (five-day), BOD₂₀ (twenty-day), BOD (full), in this case the oxidation is finished.

According to « Rules of surface waters protection from pollution » the water quality of a reservoir after sewage disposal should meet to the following basic requirements: quantity of dissolved О₂ should be not less than 4 mg / l; BOD (full) at 20 С is not higher than 3 mg/l. The contents of weighed substances in water after sewage discharge should not be increased more than in 0,25 and 0,75 mg /l for reservoirs I and II correspondently, a mineral sediment is no more than 100 mg /l; including chlorides is 350, sulfates is 500 mg / l; odour and smacks of water should absent; a surface of water should not contain the floating impurities, films, spots, oils, oil products, poisonous substances.

3. Adaptations of organisms to conditions of environment

Adaptations are various adaptations to the inhabitancy, which organism develops during evolutions. Adaptations are developed at different levels of the organization of alive matter. Ability to adaptation is one of basic properties of the alive matter, providing an opportunity of its existence. Adaptations are developed under action of three basic factors: a heredity, variability and natural (and also artificial) selection.

There are three basic ways of the organism adaptation to conditions of the environment: an active way, a passive way and avoiding adverse influences.

Active way is strengthening of resistibility, development regulatory processes, which make it possible to carry out all vital functions of organism, despite of deviations of factor from an optimum. For example, maintenance of a constant body temperature of warm-blooded animal (birds and mammals), which is an optimum for proceeding biochemical processes in cells.

Passive way is a submission of vital functions of an organism to change of environment factors. For example, transition under adverse conditions of environment in a condition of anabiosis (the latent life) when the metabolism in organism is practically completely stopped (winter rest of flowerings, preservation of seeds and dispute in soil, catalepsy of insects, hibernation of vertebrate animals, etc.).

Avoiding of adverse influences is a development by organism of such life cycles and behavior which makes it possible to avoid adverse influences, for example, seasonal migrations of animals.

Usually species adaptation to environment is carried out by that or other combination of all three possible ways of adaptation.

Adaptations can be divided into three types: morphological, physiological and ethological.

Morphological adaptations are accompanied by change in a structure of organism (for example, modification of a plants leaf of deserts). Morphological adaptations of plants and animals result in formation of the certain vital forms.

Physiological adaptations are changes in physiology of organisms (for example, ability of a camel to provide an organism by moisture by oxidation of fat stocks).

Ethological adaptations are changes in behaviour (for example, seasonal migrations of mammals and birds, a hibernation confluence of the winter period). Ethlogical adaptations are characteristic for animals.

Alive organisms are well adapted for periodic factors. Acyclic factors can cause illnesses and even death of the alive organism. The person uses it, applying pesticides, antibiotics and other acyclic factors. However, long influence of these substances also can cause adaptation to them.