Biosphere is the habitat of living organisms in which the organisms living in lithosphere, hydrosphere and organisms living in the atmosphere, their mutual interactions and relationships are included.
Structure of the biosphere: The lithosphere, hydrosphere and atmosphere are included in the structure of the biosphere.
The description of these organs of the biosphere is as follows:
1. Lithosphere: The lithosphere is the solid part of the Earth, which is spread in about 29.2 percent of the entire Earth in the form of continents and islands. Its upper surface is made of unorganized soil, under which rocks are found. But the upper surface of the Earth’s surface is important, because all the organisms receive nutrition only from the soil obtained on the lithosphere.
2. Hydrosphere: Ocean is present at over 70.8 per cent of the entire Earth. If rivers, ponds and other aquatic sources are also included in it, then about 72 per cent of the Earth’s surface is covered with water, which is called hydrosphere. Water is the second most important requirement of the organisms after oxygen, so water has been called life. The human body’s requirement of oxygen and hydrogen is met by the availability of water.
According to an estimate, about 1360 million cubic km. of water is available on the Earth’s surface, out of which 97 per cent i.e., 1320 million cubic km is located in the oceans, approximately 30 million cubic km. of water is located in the form of ice and less than 1 per cent is available in the form of underground water. The water available on the surface of the Earth is converted into a cyclic flow and then it falls on Earth in the form of rainfall by the process of condensation.
3. Atmosphere: An envelope of gaseous mixture is found surrounding the earth’s surface, which is called the atmosphere. This part stretches from the surface of the Earth to the height of thousands of kilometers. There are many types of gases, water vapor and dust particles mixed in it. The combination of these elements is not universally found, but it varies with varying height, latitude, weather, etc.
The lowest percentage of the atmosphere is found in the troposphere, except the water vapor and dust particles, and the average percentage of other gases is found almost everywhere, because the flowing nature of winds, air pressure and temperature keeps their proportion constant.
