Physical components like light, heat from sun, air, water and soil etc constitute Abiotic Environment. Soil and land region of earth is known as Lithosphere, Water regions of earth is known as Hydrosphere and gases in the air is known as Atmosphere.

1. Solar Energy :
Sun is the main source of energy on the earth. Sun is 90,960,000 miles away from the earth. All living beings on earth depend on sun for energy. Sun's radiation on earth is not equal because of elliptical shape of earth. This is the reason for difference in temperatures in different places which led to the formation of deserts, poles and temperate zones.
Solar energy is the main source for growth and development of living organisms. Green plants use solar energy and prepare their food. Solar energy is also essential for some biochemical reactions in animal bodies. It is also essential for regulating the production of growth factors in living organisms.

2. Air:
There are many gases like oxygen, carbondioxide, nitrogen, water vapor and others in the air surrounding us. The composition of these gases is balanced in the air. Living organisms help to maintain this balance. They cannot survive without air. They breath in oxygen and breath out carbondioxide during respiration.

3. Water :
70% of earth is covered by water. The body of. living organisms consists of 70% - 75% of water. Water is used in many ways by animals and plants.Plants use water for photosynthesis, germination of seeds and in absorption of salts, nutrients and manure.Animals have lot of water in their body. Water is required for the transport of gases, liquids and digested food, also for excretion of waste material, reproduction and development. In the atmosphere water is present in the form of water vapor. During day time water absorbs heat from the atmosphere and keeps surroundings cool. Water is also useful for the formation of clouds and rainfall.

4. Soil :
Soil covers 30% of the earth. Soil is formed from rocks. Hence it is called lithosphere. Top soft layer of soil is known as humus. Animals that live in air, water and soil depends on soil. Soil is necessary for the growth of plants. It supplies nutrients, salts ,to plants. It fixes the plant firmly. Bacteria which live in soil decompose the dead animals and plants and make the soil fertile. Soil is essential for livelihood of living organisms.