Class 8 Science - Chapter Crop Production and Management NCERT Solutions | What is irrigation? Describe two methods
What is irrigation? Describe two methods of irrigation which conserve water.
Irrigation: The process of watering the crops at different intervals is called irrigation. The time and frequency of irrigation varies from crop to crop, soil to soil and seasons to seasons. Two methods of irrigation that conserve the water are as follows:
- Sprinkler system: This method is used in mainly uneven or irregular shape land where sufficient water is not available or shortage of water occurs. The perpendicular pipes that contains rotating nozzles on the top, are joined to the main pipeline at regular intervals. When water is allowed to flow through the main pipe under pressure with the help of a pump then it escapes from the rotating nozzles. It gets sprinkled on the crop as like it is raining.
- Drip irrigation: In this system, a network of narrow pipes or tubes is laid down in the field with small holes. When water flows through the narrow pipes, it falls drop by drop just near the roots of the plants. In this method, there is no wastage of water occurs as the water falls down drop by drop, therefore this system of irrigation is very useful in those regions where availability of water is poor. It is the best technique for watering the fruit plants, gardens and trees.
More Questions From Class 8 Science - Chapter Crop Production and Management
- Q:-
Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
- Q:-
Complete the following word puzzle with the help of clues given below.
Down
1. Providing water to the crops.
2. Keeping crop grains for a long time under proper conditions.
5. Certain plants of the same kind grown on a large scale.Across
3. A machine used for cutting the matured crop.
4. A rabi crop that is also one of the pulses.
6. A process of separating the grain from chaff.
- Q:-
If wheat is sown in the kharif season, what would happen? Discuss.
- Q:-
Write a paragraph in your own words on each of the following.
(a) Preparation of soil (b) Sowing
(c) Weeding (d) Threshing - Q:-
Explain how fertilisers are different from manure.
- Q:-
Match items in column A with those in column B.
A B
(i) Kharif crops (a) Food for cattle
(ii) Rabi crops (b) Urea and super phosphate
(iii) Chemical fertilisers (c) Animal excreta, cow dung urine and plant waste
(iv) Organic manure (d) Wheat, gram, pea
(e) Paddy and maize - Q:-
Give two examples of each.
(a) Kharif crop
(b) Rabi crop - Q:-
Explain how soil gets affected by the continuous plantation of crops in a field.
- Q:-
What are weeds? How can we control them?
- Q:-
Select the correct word from the following list and fill in the blanks.
float, water, crop, nutrients, preparation(a) The same kind of plants grown and cultivated on a large scale at a place is called _____________.
(b) The first step before growing crops is _____________ of the soil.
(c) Damaged seeds would _____________ on top of water.
(d) For growing a crop, sufficient sunlight and _____________ and _____________ from the soil are essential.
Popular Questions of Class 8 Science
- Q:-
Which of the following can be beaten into thin sheets?
(a) Zinc (b) Phosphorus (c) Sulphur (d) Oxygen - Q:-
Fill in the blanks
(a) Most liquids that conduct electricity are solutions of , ______________ and ______________.
(b) The passage of an electric current through a solution causes ______________ effects.
(c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the terminal of the battery.
(d) The process of depositing a layer ofany desired metal on another material by means of electricity is called . - Q:-
Give two examples each of situations in which you push or pull to change the state of motion of objects.
- Q:-
Fill in the blanks:
(a) Friction opposes the _____________ between the surfaces in contact with each other.
(b) Friction depends on the _____________ of surfaces. (c) Friction produces __________.
(d) Sprinkling of powder on the carrom board ________ friction.
(e) Sliding friction is ___________ than the static friction. - Q:-
List conditions under which combustion can take place.
- Q:-
Indicate whether the following statements are True (T) or False (F).
(a) Unicellular organisms have one-celled body. (T/F)
(b) Muscle cells are branched. (T/F)
(c) The basic living unit of an organism is an organ. (T/F)
(d) Amoeba has irregular shape. (T/F) - Q:-
Which of the following cannot be charged easily by friction?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth. - Q:-
Fill in the blanks:
(a) A place where animals are protected in their natural habitat is called .
(b) Species found only in a particular area is known as .
(c) Migratory birds fly to far away places because of changes. - Q:-
Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.
- Q:-
What are the different ways in which water gets contaminated ?
Recently Viewed Questions of Class 8 Science
- Q:-
List sources of noise pollution in your surroundings.
- Q:-
The sound from a mosquito is produced when it vibrates its wings at an average rate of 500 vibrations per second. What is the time period of the vibration?
- Q:-
Complete the cross-word puzzle using the hints given below
Across
1. The process of the fusion of the gametes.
6. The type of fertilization in hen.
7. The term used for bulges observed on the sides of the body of Hydra.
8. Eggs are produced here.Down
2. Sperms are produced in these male reproductive organs.
3. Another term for the fertilized egg.
4. These animals lay eggs.
5. A type of fission in amoeba. - Q:-
Name the unit in which the calorific value of a fuel is expressed.
- Q:-
In the following statements, tick T against those which are true, and F against those which are false:
(a) Sound cannot travel in vacuum. (T/F)
(b) The number of oscillations per second of a vibrating object is called its time period. (T/F)
(c) If the amplitude of vibration is large, sound is feeble. (T/F)
(d) For human ears, the audible range is 20 Hz to 20,000 Hz. (T/F)
(e) The lower the frequency of vibration, the higher is the pitch. (T/F)
(f) Unwanted or unpleasant sound is termed as music. (T/F)
(g) Noise pollution may cause partial hearing impairment. (T/F) - Q:-
Should the handle and bristles of a tooth brush be made of the same material? Explain your answer.
- Q:-
Gurmit wanted to perform Activity 16.8 using a laser torch. Her teacher advised her not to do so. Can you explain the basis of the teachers advise?
- Q:-
Choose the correct option.
(a) Adolescents should be careful about what they eat, because
(i) proper diet develops their brains.
(ii) proper diet is needed for the rapid growth taking place in their body.
(iii) adolescents feel hungry all the time.
(iv) taste buds are well developed in teenagers.(b) Reproductive age in women starts when their
(i) menstruation starts.
(ii) breasts start developing.
(iii) body weight increases.
(iv) height increases.(c) The right meal for adolescents consists of
(i) chips, noodles, coke.
(ii) chapati, dal, vegetables.
(iii) rice, noodles and burger.
(iv) vegetable cutlets, chips and lemon drink. - Q:-
Explain in what way noise pollution is harmful to humans.
- Q:-
Boojho made the following sketch (Fig. 17.29) of the solar system. Is the sketch correct? If not, correct it.
- All Chapters Of Class 8 Science
- All Subjects Of Class 8