Environment exhaustible and inexhaustible natural resources

CHAPTER 2. ENVIRONMENTAL DANGER FOR THE HUMAN

Environment exhaustible and inexhaustible natural resources

The concept «environment» includes all natural elements, and also part of nature changed by people activity (settlements, agricultural areas, reservoirs and others). By natural resources we understand objects, conditions and processes, which are used or can be used in manufacturing for sufficing material, scientific and cultural needs of society.

The natural resources are divided into exhaustible and inexhaustible.

Inexhaustible natural resources include space (solar radiation and energy of marine flows and waves) and climatic (wind power and Earth bowels) power resources. Taking into account huge masses of air and water medium of the planet atmospheric air and water resources can be referred to inexhaustible resources too. But such reference is conditional, because chemical structure and physical condition of atmosphere and hydrosphere get changed under people activity influence (anthropogenous influence) what can bring to losses of their biological value and possibilities of using. That makes necessary to execute a complex of works on supporting air and water purity.

Exhaustible resources in turn include renewable and nonrenewable natural resources. The renewable resources can be recreated during their using. The renewing goes at various velocities: formation of 1 cm of humus ground layer takes about 600 years, growing of cut down wood - dozens of years, animals' population – up to 10 years. Thus, the rate of renewed resources using should be in balance with rate of their restoring. Nonrenewable natural resources are those which can't be renewed absolutely or their renewing goes slower than their using. Minerals which using entail over crop refer to such resources. Their protection should consist in economic, rational and complex using so resources will have a minimum loss. Besides, nonrenewable resource is the space people live in.

Every year they extract from bowels of the Earth 4 km³ of rock, hundred millions tons of gases, solids and liquids are evolved polluting surroundings. Consequently unequal manufacturing development northern hemisphere has 93.5 % of industrial emissions and southern - only 6.5 %. Wood, fish, fresh water get used up ever more. About 10 % of Earth surface has been occupied by construction of cities, roads, pipelines etc. Hydraulic engineering structures (dam, channels and artificial reservoirs) change the rivers more than natural processes for thousands of years.

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