NCERT Class 7 Science Chapter 16 Water: A Precious Resource Summary and Notes PDF

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NCERT Class 7 Science Chapter 16 Water: A Precious Resource 

Water is one of the elements of Earth, that is required for all living organisms to survive. From a seedling to a full-grown adult, we all require water in our daily lives to carry on with life. This is why water is a very precious resource and we all should aim towards saving, preserving, and harvesting it. Did you know, we humans constitute 72% of water? Water in itself has a life.

From the moment when a planting is planted in the soil, till it starts to bud flowers, it requires water at every stage of its life. Buildings we live in, are made of cement that is mixed with water so bricks can be joined together. The air carries water with it contributing to the clouds. Food that we eat requires water to cook. You see, how everything around us needs water in some or the other way. This is why water is such an important natural resource.

Water is how our Earth sustains life. It is the manufacturing tool of survival. Therefore, in this article, we will be looking into a chapter that talks about how important water is, what roles it plays, forms of water, depletion of water, distribution of water, and so on. The chapter being summarized below is NCERT Class 7 Science Chapter 16 Water: A Precious Resource.

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource Introduction

The chapter, NCERT Class 7 Science Chapter 16 Water: A Precious Resource, begins with a Hindi saying that says "jal hai toh kal hai" which translates to, if you have water, you have a tomorrow. This saying exactly points out how much of a precious resource water is. 

The amount of water recommended by the United Nations for drinking, washing, cooking, and maintaining proper hygiene is a minimum of 50 liters per person per day, says a report in this chapter, NCERT Class 7 Science Chapter 16 Water: A Precious Resource.

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource Summary

Why does the Earth appear blue? Because 71% of our Earth's surface consists of water. Yet, more than half of it is salty water which is not fit for drinking, household chores, cooking, and other tasks. The water that is consumable by us is freshwater which, day by day, is decreasing at a high rate. Therefore, 22nd March is celebrated as World Water Day. So, more and more people start taking action to save water, use only much as they need, reserve it as well as harvest the same. 

Many places all over the globe are facing acute problems where taps run out of water, water supplied is only once or twice over a year, protests break out, and the situation worsens during summers. 

Let's talk about a phenomenon called "The Water Cycle", we all must be familiar with this in the chapter NCERT Class 7 Science Chapter 16 Water: A Precious Resource. The cycle begins with the water bodies (lakes, rivers, seas, oceans, etc.) evaporating because of high temperatures (a gaseous form of water), these evaporated water drops collect themselves in the air inside the clouds, and when these clouds get heavy and are pushed by the air, they release rain (the liquid form of water) or at times, snow (solid form of water). So, the water flows back down into the water bodies. It forms a complete cycle. 

Groundwater, as the name tells, water that is found digging deep into the ground, is called groundwater. It is a very significant and valuable source of water. When we talk about groundwater, we cannot miss one important detail. The water table. The space where the soil particles and gaps in the ground are filled with water is the water table. Due to population, agriculture, and industrial activities, this water table is being depleted.

The distribution of water is uneven, not equally distributed, which is why water resources are not available throughout the world in a proper way. Talking about, India is a country with vastness, wilderness, and diversity. Rainfall is not equal in every corner of the country. So, quite a few states in India are water resource deprived. There have been cases of famines in desert regions during summers. Therefore, water management is very important.

To help in the concern of saving water, what can you do? Get the leaking taps fixed, use just as much water as you require to bathe instead of letting the shower on for several minutes, and don't wash the floors, mop them instead. There are many other ways you can chip in help. Lastly, what effect does water have on plants? 

Potted plants, if not watered regularly, wilt and dry up. Exactly like how we require water every day, so do plants regularly. If we don't preserve water, plants and trees will lose their lives, and without the greens, we cannot imagine our world being as alive and sustainable as it is now. Plants are our source of food, rain, oxygen, soil, and various other factors.

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource Notes

Following are brief notes covering all topics in NCERT Class 7 Science Chapter 16 Water: A Precious Resource.

Introduction: 22nd March is World Water Day, celebrated to draw people's attention to how precious resource water is. Water is a colorless, odorless element that exists in 3 forms: solid, liquid, and gas.

Percent of water on Earth: Earth's surface consists of 71% of water. In this 71%, the amount of freshwater compared to the water of seas and oceans is as low as 3%. 

Water Cycle: A natural phenomenon that involves a cyclic process of water transfer. It begins with the water bodies evaporating due to temperature and humidity, the evaporated water droplets transfer to the air as vapors (gaseous form) and get collected into clouds. These clouds then release these droplets either in the form of rain or snow. 

Water Table: On exploring further into the Earth's surface, there comes a level where soil particles and rocky gaps are filled with gushing water. That groundwater level is termed the water table. This table varies from place to place depending on how much water that area receives. 

Infiltration: When water trickles down into the ground.

Aquifer: Place where groundwater is warehoused between the levels of rocks and down below the water table.

Depletion of water: Depletion of water means the reduction of water or decrease of water from the Earth's surface due to man-induced activities like mining, agriculture, increasing population, and industrial activities.

Water Distribution: Due to the unequal distribution of water, because of the world geography, water is not available fairly over the globe. On one hand, rainforests have plenty of rain, and on the other hand, deserts have negligible rain.

Water Management: Managing water by investing our efforts so as to save water is called water management. There are various ways one can do the same. Rainwater harvesting, closing the taps off when not in use, fixing tap leaks, using drip irrigation in agricultural practices wherever it is possible to implement, and so on.

Effects of Water Scarcity on Plants: Plants, especially potted plants, will dry and wilt up when enough water is not provided to them. Plants and trees are alive on 3 vital factors, water, soil, and sunlight. If we lose the greens on our planet, we are putting ourselves to risk.

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource Notes PDF Download

Below you can download the notes of NCERT Class 7 Science Chapter 16 Water: A Precious Resource.

NCERT Class 7 Science Chapter 16 Water: A Precious Resource PDF Download

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource Notes Conclusion

To conclude, the chapter, NCERT Class 7 Science Chapter 16 Water: A Precious Resource, says that saving water is looking out for our future. 

Water is a crucial element that all living beings deeply rely on. No life is proven to live without the indispensable factor, of water. 

Water has three forms in which it exists, solid, liquid, and gas. Although the water cycle seems to display how water is managed in nature but because of the development of agriculture and industries, water is being polluted and is scarce all over the world.

71% of the Earth is constituted of water. 3% of which is fresh water, the only form we can consume water from. Due to the boosting growth of the population, water is driving into acute shortage. We should look after negligible wastage of water, unnecessary use, and overdrawing of water from the ground.

Groundwater is a very important source of water and we should preserve it. Plants cannot survive long without water. 

 

NCERT Class 7 Science Chapter 16 Water: A Precious Resource FAQs

Here are a few questions for a quick recap of NCERT Class 7 Science Chapter 16 Water: A Precious Resource.

 

1. When is World Water Day celebrated?

Answer: 22nd Marc

2. How much of the earth's surface consists of water?

Answer: 71%

3. What three forms does water exist in?

Answer: Solid, Liquid, and Gas

4. Briefly explain the water cycle.

Answer: A natural phenomenon that involves a cyclic process of water transfer. It begins with the water bodies evaporating due to temperature and humidity, the evaporated water droplets transfer to the air as vapors (gaseous form) and get collected into clouds. These clouds then release these droplets either in the form of rain or snow. 

5. What do you understand by the water table?

Answer: n exploring further into the Earth's surface, there comes a level where soil particles and rocky gaps are filled with gushing water. That groundwater level is termed the water table. This table varies from place to place depending on how much water that area receives. 

6. In short explain: Infiltration and Aquifer

Answer: 

Infiltration: When water trickles down into the ground.

Aquifer: Place where groundwater is warehoused between the levels of rocks and down below the water table.

7. How can you help save and manage water?

Answer: Rainwater harvesting, closing the taps off when not in use, fixing tap leaks, using drip irrigation in agricultural practices wherever it is possible to implement, moping the floors instead of washing, etc.