Variant – 2

1. Pedosphere (a soil cover) as a part of biosphere

The pedosphere (from Greek πέδον pedon "soil" or "earth" and σφαίρα sfaíra "sphere") is the outermost layer of the Earth that is composed of soil and subject to soil formation processes. It exists at the interface of the lithosphere, atmosphere, hydrosphere and biosphere. The sum total of all the organisms, soils, water and air is termed as the "pedosphere". The pedosphere is the skin of the Earth and only develops when there is a dynamic interaction between the atmosphere (air in and above the soil), biosphere (living organisms), lithosphere (unconsolidated regolith and consolidated bedrock) and the hydrosphere (water in, on and below the soil). The pedosphere is the foundation of life on this planet. There is a realization that the pedosphere needs to be distinctly recognized as a dynamic interface of all terrestrial ecosystems and be integrated into the Earth System Science knowledge base. Also, the pedosphere needs to be studied, valued, enhanced and treated in a sustainable and an ethical manner.

The pedosphere acts as the mediator of chemical and biogeochemical flux into and out of these respective systems and is made up of gaseous, mineralic, fluid and biologic components. The pedosphere lies within the Critical Zone, a broader interface that includes vegetation, pedosphere, groundwater aquifer systems, regolith and finally ends at some depth in the bedrock where the biosphere and hydrosphere cease to make significant changes to the chemistry at depth. As part of the larger global system, any particular environment in which soil forms is influenced solely by its geographic position on the globe as climatic, geologic, biologic and anthropogenic changes occur with changes inlongitude and latitude.

2. Dry Dust removal equipment

The dust removal equipment available may be divided into two large groups: Dry dust removal equipment and wet dust removal equipment. For both groups: A few representative examples will be discussed.

In dry dust removal equipment dust separation from the carrier gas is achieved directly i.e. in the dry state, without the use of a special dust collection agent like water drops. The collected dry dust can be directly disposed of. The use of dry dust removal equipment involves however the danger of dust explosion. Therefore, special measures have to be taken to prevent dust explosion and pressure release in case of explosion.

The separation of dust particles from a gas is mainly due too the action of three forces: inertia force, surface or adhesion force, and electrical force. In most of the dry dust separators, one force dominate over the other thus determines the separation process. According to the prevailing force there are three groups of the dry dust removal equipment:

1. Mass force separator.

2. Adhesion force separator.

3. Electrical force separator.

A typical mass force separator is the cyclone. Under the action centrifugal forces, the dust particles are separated from the gas phase. Conventional adhesion force separators are bag and pocket filters. A typical electrical force separator is the plate precipitator. The three types of dry dust separators are schematically illustrated in Fig. 1.

The cyclone consists of entrance chamber, vortex chamber, dust collection chamber and gas exit tube, the letter extending into the interior of the cyclone. The gas is introduced tangentially so that a rotational movement of gas and dust particles is obtained. Due to this rotational motion, centrifugal forces result which carry the dust particles toward the wall entrance and vortex chamber. The cyclone separates the dust continuously.

3. Classification of community.

Classification of community. Community is differed in sizes and a degree of «genetic independence», duration of existence, a way of breeding of species, etc.

Depending on sizes of occupied community of territory and communication degree between species there are elementary (local), ecological and geographical communities. The elementary (local) community is an elementary grouping of the species, described practically full panmixia. Ecological community is a totality of spatially adjacent elementary communities. A geographical community is a totality of groups of spatially adjacent ecological communities.

According to ability to self-reproduction and independent evolution there are permanent (constants) and (time) communities. Permanent (constants) communities are ones which are rather steadily in space and in time and which are capable to unlimitedly long self-reproduction, are elementary units of evolution. Time communities are ones which are unstable in space and in time and unable to long self-reproduction. Eventually or they will be transformed in permanent, or they will disappear.

Depending on breeding, communities are divided into panmictic, clonal and clonal-panmictic. Panmictic communities consist of the species, breeding by sexual way for which cross impregnation is characteristic. Clonal communities consist of species for which only sexual breeding is characteristic. Clonal-panmictic communities are formed by species with alternation sexual and sexual breeding.

communities, being group associations, possess a number of specific properties which are not inherent in each separate individual: number, density, birth rate, death rate, growth rate, etc. In addition to this, community has certain organization: sexual, age, genetic, spatially and other structures.