The document discusses the key components of the environment - air, water, and soil. It provides details on:
1) The composition of air and its importance for supporting life through oxygen and carbon dioxide.
2) The distribution and sources of water on Earth, including surface water, groundwater, and desalination. Water is essential for agriculture, drinking, washing, fire extinction, recreation, and industrial applications.
3) The importance of soil in supporting plant and animal life, and ultimately human life. Soil properties like color and texture impact its ability to sustain growth.