WATER: A PRECIOUS RESOURCE (PART-2) class 7

WATER: A PRECIOUS RESOURCE

Q.5. What are the sources of groundwater for human consumption? 

Ans. The rainwater and water from other sources such as rivers and ponds seeps through the soil and fills the empty spaces and cracks deep below the ground. The groundwater thus gets recharged by this process.

Q.6. Differentiate between groundwater and water table. 

Ground water

Water table

Ground water comes from the natural seeping, also called percolation of different forms of precipitation and other surface waters down through the earth’s soil.

The upper level of the ground water is called the water table.

It is a broader source which contains all water table, aquifer etc.

Water table is a part of ground water.

Q.7. Name the factors which are responsible for depletion of water table 

Ans. The factors which are responsible for depletion of water table are:

Increase in population, industrial and agricultural activities are some common factors affecting water table. Scanty rainfall, deforestation and decrease in the effective area for seepage of water are also other factors that may deplete the water table.

Q.8. Why do the laborers have to bore the ground at the construction sites?

Ans. At the construction sites as construction goes on so they must not be having authorized water connections for water supply. So, the laborers have to bore the ground at the construction sites to reach the water table and get water for construction.


Q.9. Explain the following terms:

   a) Drip irrigation: 
Ans. Drip irrigation is a technique of watering plants by making use of narrow tubings         which deliver water directly at the base of the plant. In this system, the water falls             drop by drop directly near the roots. So it is called drip system. It is the best technique      for watering fruit plants, gardens and trees. Water is not wasted at all. 
     It is a boon in regions where availability of water is poor.


    b) Rain water harvesting:

      It is a unique method of water conservation of gathering and collecting rain water to       recharge the groundwater. This is referred to as water harvesting water harvesting or        rainwater harvesting.

      There are two ways to harvest rain water are Surface run-off harvesting and  Rooftop        rainwater harvesting.

Q.10. Write a short note on bawris. 

Ans. Bawri was the traditional way of collecting water for storage and water recharge. Bawris are deep step-wells built into the ground. When it rains, the rain accumulates in these tanks and because these tanks are very deep, the water does not evaporate easily and this water can be used during times of storage.

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