Main Elements of Environment:
(a) Air:
The atmosphere is a layer of gases surrounding the earth up to 900 km high. It consists mainly of nitrogen (78.09%) and oxygen (20.94%), with smaller amounts of other gases and water vapour. Air is essential for life—it provides oxygen for animals and carbon dioxide for plants. It also plays a vital role in weather phenomena like clouds, wind, and rain.
(b) Water:
Water is essential for all life forms. It covers nearly three-quarters of the earth’s surface in the form of oceans, seas, rivers, lakes, and ice sheets. While most water is salty and found in oceans, freshwater is limited and found in rivers, lakes, rain, and ice. Water supports daily activities, agriculture, industry, and transportation. Civilizations have historically flourished near water sources.
(c) Soil:
Soil is the top layer of the Earth’s crust and supports plant life. It is composed of minerals, organic matter, and microorganisms. Soil is vital for providing nutrients to plants and is a habitat for various organisms. Fertile soil supports agriculture and human prosperity, while soil health depends on the presence of beneficial microbes that help maintain fertility and reduce erosion.