Natural environment

Environment: totality that includes four components: atmosphere, hydrosphere, lithosphere and biosphere.

Atmosphere: the gaseous envelope surrounding the earth and reaches about 3000 km from the earth surface. Modern atmosphere consists of: 78.1% nitrogen, 20.93 % oxygen, 0.08% argon, 0.027% carbon dioxide, and additionally it contains helium, neon, xenon, krypton, hydrogen, ozone, ammonia etc.

Hydrosphere: the watery part of the earth's surface, including oceans, lakes, water vapor in the atmosphere, etc (fig. 1).

Fig. 1 Earth waters chart

Lithosphere: the rigid outer layer of the earth, having an average thickness of about 75 km and comprising the earth's crust and the solid part of the mantle. 99.5 % of earth's crust are made from 8 components: oxygen, silicium¸ hydrogen, aluminum, iron, magnesium, calcium, sodium. Amount of oxygen and silicium makes 75 % of the total.

The top layer of the land surface of the earth that is composed of disintegrated rock particles, humus, water, and air is soil.

Biosphere: the part of the earth's surface and atmosphere inhabited by living things. The upper limit of biosphere reaches 20-25 km height to the lower boundary of ozone layer. And its lower limit lays at 23 km depth from dry land (bacteria in oil layer) and 1-2 km lower ocean bottom.

The highest achievement of biosphere development advanced by mankind became forming the sphere of mind, civilization – noosphere.

Дата добавления: 2014-01-04