Water
Introduction
• Water is one of the most important naturalresources.
• It is one of the basic necessities forsurvival.
Uses of Water
Sources of Water
States of Water
• In nature, water is the only substance which exists in all the three states- solid, liquid andgas
Processes Involved in the Water Cycle
• During the water cycle in nature, the water goes through changes ofstate.
• Many physical processes such as evaporation, transpiration, condensation,
freezing and melting are involved in the watercycle.
Importance of Water Cycle
• It makes fresh water available in the form ofrain.
• It keeps the amount of water on the Earth’s surfaceconstant.
Rains
Importance of Rain
• Rains bring relief by cooling the environment after the hot summerseason.
• The sowing of many crops depends on the arrival of rain duringmonsoon.
• Rains provide water to the rivers and dams of hydroelectric powerplants.
• Rains fill up lakes and ponds which act as sources ofwater.
• Rains get accumulated in the form of groundwater which gets stored under the surface of theEarth.
Adverse Effects of Rain
Conservation of Water
• Water is a very precious resource. Life on Earth will continue only as long as we have enough clean water.
• We should try to save water by controlling the amount of water which weuse.
• We should be careful and use only as much water as required.
Measures to Conserve Water
Harvesting
Rainwater which falls on roofs and terraces of buildings can be collected through pipes and stored in underground
tanks or can be allowed to percolate into the soil and used to recharge the groundwater table.
This is called water harvesting or rainwater harvesting.
