CLASS-VIII: SCIENCE: CONSERVATION OF PLANTS AND ANIMALS

CLASS VIII  |   SCIENCE   |  CHAPTER 7

           notes prepared by Subhankar Karmakar

Chapter 7: conservation of plants and animals

Q1) Define biosphere.

Ans: Biosphere is that part of the earth in which living organism exist. It includes land surface of the earth, atmosphere of the earth, as well as water bodies on the earth.

Q2) What do you understand by the term wildlife? 

Ans: The term wildlife means all the animals and plants which are found naturally in the forest and other natural habitats.

Q3) What is biodiversity? 

Ans. Biodiversity refers to the variety of organisms like plants animals and microorganism etc better found in a particular area of habitat.

Q4) What is an ecosystem?

Ans: A system which includes all the living organisms like plants animals and microorganisms of an area and the physical environment like soil air and water in which they live are together called an ecosystem.

Q5) What is deforestation?

Ans: The tearing of forest by cutting down forest trees over a wide area is called deforestation.

Q6) What are the various causes of deforestation?

Ans: The various causes of deforestation are

i) the forest trees are cut down to obtain wood for using as fuel

ii) the forest trees are cut down to obtain doors, windows and furniture.

iii) the forest trees are cut down to obtain wood for making paper.

iv) the forest trees are cut down to obtain more agricultural land for cultivation of crops for the increasing population.

v) the forest trees are cut down to get land for building houses, factories, roads and dams etc.

Q7) What are the consequences of deforestation?

Ans: The consequences of deforestation are 

i) deforestation will lead to a shortage of wood and other forest products

ii) deforestation will cause an increase in temperature of Earth's atmosphere leading to global warming.

iii) deforestation will cause soil erosion making the soil infertile and lead to desertification.

iv) deforestation will cause frequent flooding of rivers leading to loss of life and property.

v) deforestation affects the water cycle leading to decrease in rainfall. The decrease in rainfall lowers  the groundwater level and could cause droughts.

vi) deforestation leads to the extinction of many wild animals and plants.

Q12) Name some biosphere reserves of India.

Ans: There are several biosphere reserves in India. 

These are

1. great nicobar biosphere reserve

2. Kaziranga biosphere reserve

3. Sundarbans biosphere reserve

4. Kanha biosphere reserve

5. Pachmarhi biosphere reserve

Q13) What are the roles of biosphere reserve?

Ans: The biosphere reserves perform the following roles

1. It help in conservation of wildlife of the area

2. It help to maintain the biodiversity of the area.

3. It preserve the natural ecological conditions in the area.

4. It promotes the economic development of the area.

5. It helps to maintain the lifestyle the tribal people living in the area

6. It prevents the commercial exploitation of the area.

7. It provides opportunities for scientific research, environmental education and tourism.

Q14) What do you understand by flora and fauna?

Ans: The plants that grow naturally in a particular area are called Flora of that area and the animals which live naturally in a particular area are called fauna of that area. As an example, Teak, jamun, fern, mango, Arjun are the flora of pachmarhi biosphere reserve and cheetal, wolf, Leopard, chinkara, blue bull, barking deer and wild dog are the examples of fauna of the pachmarhi biosphere reserve.

Q15) What are endemic species of a particular area?

Ans. Endemic species are those species both of plants and animals which are found exclusively in a particular area. The plants and animals which are found only in a particular area are said to be endemic to that area. As an example sal and wild mango are the two examples of the endemic flora of the pachmarhi biosphere reserve and giant squirrel, flying squirrel and bison are the three examples of endemic fauna of the pachmarhi biosphere reserve area.

Q16) Explain biosphere reserve.

Ans: A biosphere reserve is a large, protected area of land meant for the conservation of wildlife, biodiversity, and the traditional lifestyle of the tribal people living in the area. A special feature of the biosphere reserve is that local people or tribals are an integral part of it.

Q17) What are the different zones in a biosphere reserve?

Ans: A biosphere reserve has been divided into 3 zones.

i) The innermost zone of a biosphere reserve is known as core zone. It is devoted to strict protection of wildlife. No human activity e is allowed in the core zone of a biosphere reserve.

ii) The middle zone of a biosphere reserve is called buffer zone. Buffer zones around the core zone and limited human activity  is allowed here.

iii) The outermost zone of a biosphere reserve is called transition zone. In the transition zone several non destructive human activities such as settlements of tribals and cultivation of crops are allowed.

Q18) What are the different types of protected areas which have been established by the government for the conservation of forest and wild animals?

Ans: There are three types of protected areas established by government for the conservation of forest and wild animals. These are

i) biosphere reserves

ii) wildlife sanctuaries

iii) national parks

Q19) Why do we need protected areas forest and wildlife conservation?

Ans: The purpose of establishing several biosphere reserves, wildlife sanctuaries and national parks in India is to conserve wild animals and their natural surroundings so as to maintain a healthy balance in nature and to prevent the extinction of endangered wild animals.

Q20. What is wildlife sanctuary?

Ans. Wildlife sanctuary is a protected area of land who is is created for the protection of wild animals in their natural environment like forests. Therefore a wildlife sanctuary provides protection and suitable living conditions to the wild animals in their natural habitat. In a wildlife sanctuary killing or poaching and capturing of wild animals is strictly prohibited.

Q21. Write the name of some wildlife sanctuaries of India.

Ans. There are more than 500 wildlife sanctuaries in India. The major wildlife sanctuaries are-

1. Sanjay Gandhi wildlife sanctuary in Maharashtra

2. Mudumalai wildlife sanctuary in Tamil Nadu

3. Nagarjun Sagar wildlife sanctuary in Andhra Pradesh

4. Bharatpur Bird sanctuary in Rajasthan

5. Sultanpur lake bird sanctuary in Haryana

6. Dandeli wildlife sanctuary in Karnataka

7. Thattekad Bird sanctuary in Kerala

8. Satkosia Basipalli wildlife sanctuary in West Bengal

9. Lokchao wildlife sanctuary in Manipur

10. Bori wildlife sanctuary in Madhya Pradesh.

Q22. What are the differences between biosphere reserve and wildlife sanctuary?

Ans. The main differences between biosphere reserve and wildlife sanctuary are as follows.

1. A biosphere reserve is spread over a very large area of land, where as a wildlife sanctuary occupies a comparatively smaller area of land.

2. A biosphere reserve is for the conservation of biodiversity of the area as well as the economic development of the area where as a wildlife sanctuary is mainly for the protection of wild animals of the area in their natural habitat.

3. Local tribal people form an integral part biosphere reserve where as local people is not included in a wildlife sanctuary.

4. The human activities such as cultivation of land and building of settlements are allowed in the outermost zone of a biosphere reserve where as the human activities are not allowed in a wildlife sanctuary.

Q23. What is a national park?

Ans. A National Park is a relatively large area of scenic beauty  protected and maintained by the government to preserve flora and fauna landscape history objects of the area and places of of scientific interest. Another purpose of establishing National parks is to provide human recreation and enjoyment.

Q24. Write the name of some prominent National parks of India.

Ans. Name of the some prominent National parks of India are as follows.

1. Corbett national park in uttarakhand

2. Kanha national Park in madhya Pradesh

3. Ranthambore national Park in Rajasthan

4. Gir national Park in Gujarat

5. Kaziranga national Park in Assam.

Q25. What is project tiger?

Ans. Tiger is one of the many wildlife species which are slowly disappearing from our forest. Project tiger is a world life conservation project which was launched by the government of India in 1972 to protect the tigers in the country. There are 28 tiger reserves in India at present which are governed by project tiger.

Q26. What are the main differences between a wildlife sanctuary and a national park?

Ans. The main differences between a wildlife sanctuary and a national park are as follows

1. A Wildlife sanctuary may or may not be an area of great scenic beauty but a national park is an area of great scenic beauty.

2. A wild life sanctuary protects and preserves the wild animals in their natural environments but a national park protects and preserves wild animals and their environment as well as the scenic beauty e historical objects and habitats of scientific interest in the area.

3. A wildlife sanctuary is not meant for  recreation and enjoyment of the public but in a national park in addition to protection wild animals are kept for recreation enjoyment and educated interests of the public.

4. Wildlife sanctuary is usually does not allow easy access to the visitors but a national park allows easy access for the visitors.

Q27. What is a a extinct species?

Ans. The species who is no longer exist anywhere on the earth are called extinct species. Dinosaur, dodo bird, cave lion, Caspian tiger, Irish deer are examples of extinct species.

Q28. What is an endangered species?

Ans. The species which are facing the risk of extinction are called endangered species. It means that the wild animals whose numbers are are diminishing to such a low level that they might face extinction soon are known as endangered animals. Tiger, snow leopard, great Indian rhinoceros, Asiatic lion, desert cat, lion tailed macaque, namdapha flying squirrel and Kashmir stag are some examples of endangered species.

Q29. What is a red Data book?

Ans. Red Data book is the book which keeps record of all the endangered animals, plants and other species. Some of the endangered species of animals listed in the red Data book of India are: Flying squirrel, Indian giant squirrel, Barasingha, blackbuck, Himalayan musk deer, great Indian rhinoceros, snow leopard and tiger.

Q30. What is migration?

Ans. Thr process of a bird or other animals moving from one place to another according to the season is called migration. Migration of birds for other animals is an adaptation to escape the harsh and cold conditions of their normal habitat in winter so as to survive. 

Q31. What are migratory birds? 

Ans. The birds which move from very cold region to warmer regions in winter and go back after the winter is over are called migratory birds. Migratory birds fly to far away places more than 3000 km every year. 

One of the example of migratory birds  is the Siberian crane.

Q32. What is  Recycling of paper?

Ans. Paper is made from wood pulp that is produced from the wood of the forest trees. And it causes a rapid deforestation. But we already know deforestation harms ecology very much. To save forest trees from deforestation, the used paper can be  reconverted into usable paper and that is called recycling of paper. Paper can be recycled 5 to 7 times for use.

Q33. What are the Advantage of recycled paper?

Ans. The advantages of recycling of paper are as follows.

1. Recycling of paper reduce the amount of deforestation of trees.

2. Recycling of paper saves tremendous amount water which are used in paper making.

3. Recycling of paper also save use amount of energy used in making paper.

4. It reduces the amount of harmful chemicals used in paper making.

Q34. How many full grown trees are needed to make 1 tonne of paper?

Ans. It has been estimated that 17 full grown trees are needed to make 1 tonne of paper.

Q35. What is reforestation? 

Ans. The planting of trees in an area in which forest were destroyed is called reforestation. The planted trees should generally be of the same species which wire cut down from the forest during deforestation.

Q36. What are the advantages of reforestation?

Ans. The advantages of reforestation are as follows-

1. Reforestation producers a large quantity of raw materials for industry like paper industry, timber trade etc.

2. Reforestation will lead to a decrease in global warming by reducing the amount of carbon dioxide gas in the atmosphere.

3. Reforestation increases rainfall in an area. This will raise ground water level and prevent droughts.

4. Reforestation prevents soil erosion and floods.

5. Reforestation increases the area of Earth under forest which is good for the conservation of wildlife.

Lecture 5: CLASS VIII: SCIENCE: CHAPTER 1: HARVESTING

CLASS-VIII; SCIENCE

Prepared by Subhankar Karmakar

6. HARVESTING:

The cutting and gathering of the matured food crop is called harvesting. 

MANUAL HARVESTING:

In harvesting, the crops like wheat or rice are cut close to the ground by hand using a cutting tool called sickle and this is called manual harvesting.

MACHINE HARVESTING:

In large fields, wheat and paddy crops are cut by a motorised machine called harvester.

THRESHING:

After harvesting the crop, the grains are separated from the harvested crops. The process of beating out the grains from the harvested crops plants is called threshing. It can be done manually as well as with the help of a motorised machine called thresher.

WINNOWING: 

The process of threshing brings out grains from the cut and dried crop plants, but this grain is mixed with chaff ( outer inedible covering of grain) and hay. The process of separating grain from chaff and hay with the help of wind is called winnowing.

COMBINE: 

A combine is a large machine which cuts the standing cereal crop in the fields, threshes it, and separates the chaff from grain in one operation.

Lecture-4: CLASS VIII: SCIENCE: CHAPTER -1: WEEDS

CLASS-VIII; SCIENCE

Prepared by Subhankar Karmakar

5) REMOVING THE WEEDS OR WEEDING

Weeds: The unwanted plants or wild plants which grow along with a cultivated crop are called weeds. Like some of the common weeds found in wheat and rice fields are:

(a) Wild oat 

(b) Grass

(c) Amaranthus

(d) Chenopodium

HARMFUL EFFECTS OF WEEDS:

The growth of weeds in the fields is harmful because 

(i) they consume a lot of fertilisers, water, sunlight and space, meant for the crops plants, 

(ii) weeds reduce the crop yield and lower the quality of food grains,

(iii) some weeds are poisonous for human beings and animals,

(iv) some weeds interfere in harvesting.

WEEDING: 

The process of removing weeds from a crop field is called weeding. 

VARIOUS METHODS OF WEEDING:

(a) Removal of weeds by pulling them out with hand.

(b) Removal of weeds by using a trowel ( khurpa)

(c) Destroying the weeds by spraying special chemicals called weedicides.

WEEDICIDES: 

The poisonous chemicals which are used to kill weeds in the fields are called weedicides.  Some of the common weedicides are: 2,4-D, MCPA, Butachlor. 

Lecture 3: CLASS-VIII: SCIENCE: CHAPTER 1: MANURE & FERTILIZER

CLASS VIII   |    SCIENCE    |    CHAPTER 1

      Notes prepared by Subhankar Karmakar

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Lecture 3: 

ADDING MANURE AND FERTILISERS

1. NEED OF MANURE & FERTILISERS

Repeated growing of crops in the same field removes a lot of precious mineral elements, organic matter and other materials from the soil. The deficiency of plant nutrients and organic matter in the soil is made up by adding manures and fertilisers to the soil.

2. MANURES: 

Manure is a natural fertiliser. A manure is a natural substance obtained by the decomposition of animal wastes like cow-dung, human wastes and plant residues, which supplies essential elements and humus to the soil and makes it more fertile.

3. PREPARATION OF MANURES: 

Manures are prepared from animal wastes, human wastes and plant residues by the action of micro- organisms. In order to prepare manure, farmer dump animal wastes and plant wastes in pits at open places and allow it to decompose slowly. The decomposition is carried out by some micro-organisms. The decomposed animal and plant matter is used as organic manure.

4. FUNCTION OF MANURES:

Manures provide a lot of organic matter like humus to the soil. A manure improves the soil texture for better retention of water and aeration. 

5. CHEMICAL FERTILISERS:

A chemical fertiliser is a salt or an organic compound containing the necessary plant nutrients like nitrogen, phosphorus or potassium, to make the soil more fertile. A chemical fertiliser is rich in a particular plant nutrients such as nitrogen, phosphorus or potassium (NPK). Some examples of chemical fertilisers are Urea, Ammonium sulphate, Superphosphate, Potash and NPK.

6. DIFFERENCES BETWEEN MANURES AND FERTILISERS: 

1. A manure is a natural substance obtained by the decomposition of animal wastes like cow dung, human waste and plant residue. 

But a fertilizer is a salt or an organic compound.

2. Manure is not very rich in essential plant nutrients like nitrogen, phosphorus and potassium where as fertilizers are very rich in plant nutrients like nitrogen, phosphorus and potassium.

3. A manure provides a lot of organic matter like humus to the soil but a fertilizer does not provide any humus to the soil.

4. A manure is absorbed slowly by the plants because it is not much soluble in water but being soluble in water if fertilizer is readily absorbed by the plants.

5. Menure can be prepared in the field but fertilizers are prepared in factories.

7. ADVANTAGES OF MANURE:

Organic manure is considered better than Fertilisers because of the following reasons:

1. Manure enhances the water holding capacity of the soil.

2. Manure makes the soil porous due to which the exchange of gases becomes easy.

3. Manure increases the number of useful microbes in the soil.

4. Manure improves the texture of the soil.

8. LEGUMINOUS CROPS:

The pulses, peas, beans, groundnut, gram and clover are called leguminous crops. Leguminous crops have the ability to fix atmospheric nitrogen to form nitrogen compounds. The planting of leguminous crops in a field has the same effect as adding nitrogenous fertiliser in the field.

9. CROP ROTATION:

The practice in which different types of crops like leguminous crops and non-leguminous crops are grown in the same field or soil is called crop rotation. In crop rotation, cereal crops like Wheat, Maize, Paddy and Millet are grown alternately with leguminous crops pulses, peas, beans, groundnut and clover etc. in the same field.

10. ADVANTAGES OF CROP ROTATION:

Rotation of crops has the following advantages:

1. Rotation of crops improves the fertility of the soil and hence increases the production.

2. Rotation of crops saves a lot of nitrogenous fertiliser.

QUESTIONS BANK:

21. Why does soil needs manuring?

22. What are manures? Why it is needed?

23. What are the advantages of manures?

24. What are chemical fertilisers? Give examples.

25. Differentiate between manures and fertilisers.

26. What are leguminous plants? What they are being planted in the field?

27. What are crop rotation? What are their advantages?

Lecture 2: CLASS - VIII: SCIENCE: CROPS -2: IRRIGATION

CLASS VIII   |    SCIENCE    |    CHAPTER 1

      Notes prepared by Subhankar Karmakar

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• IRRIGATION

The process of supplying water to crop plants in the fields is called irrigation. 

• Why is Irrigation Necessary: 

1. Irrigation before ploughing the fields makes the soil soft due to which ploughing of fields becomes easier.

2. Irrigation is necessary to provide moisture for the germination of seeds. This is because seeds do not grow in dry soil.

3. Irrigation is necessary to maintain the moisture of soil for healthy crop growth so as to get good yield.

4. Irrigation is necessary for the absorption of nutrient elements by the plants from the soil.

5. Water supplied to the crops during irrigation protects the crop plants from hot air currents as well as frost.

• Factors Affecting Irrigation Requirements of Crops:

The irrigation requirements of crops depend on three factors:

• 1) Nature of the crop
• 2) Nature of the soil, and 
• 3) Season.

• NATURE OF THE CROP: 

Paddy crop is transplanted in standing water and requires continuous irrigation where as other other crops like wheat, gram, cotton etc. do not require so much water. Hence irrigation depends upon the nature of the crops.

• NATURE OF THE SOIL: 

There are two types of soil on which the crops are grown, (a) Sandy soil and (b) Clayey soil. The crops grown in a Sandy soil need irrigation more frequently where as the frequency of irrigation for the crops grown in a Clayey soil is comparatively less.

• SEASON: 

The frequency of irrigation of the crops is higher in summer season.

• SOURCES OF IRRIGATION:

Crops are supplied water for irrigation from different sources like: Rivers, Canals, Wells, Tube-wells, Dams, Ponds and Lakes.

• TRADITIONAL METHODS OF IRRIGATION:

The various traditional methods of irrigation are:

i) Most (Pulley system),

ii) Chain pump,

iii) Dhekli, and

iv) Rahat ( Lever system)

• MODERN METHODS OF IRRIGATION:

The two main modern methods of irrigation are:

(a) Sprinkler system, and

(b) Drip System.

• SPRINKLER SYSTEM:

In the sprinkler system of irrigation, a main pipeline is laid in the fields. Perpendicular pipes having rotating nozzles at the top are joined to the main pipeline at regular intervals. When water from a tube- well is allowed to flow through the main pipeline under pressure with the help of a pump, it escapes from the rotating nozzles. This water gets sprinkled on the crop plants. It is more useful for the uneven land where sufficient water is not available. It is also useful for Sandy soil.

• DRIP SYSTEM:

In the drip irrigation system, there is a network of narrow pipes with small holes, in the fields. When water flows through the narrow pipes, it falls drop by drop at the position of roots of the plants. This water is absorbed by the soil in the root zone of the plants and utilised by the plants. There is no wastage of water in this type of Irrigation. Drip system is the best technique for watering fruit plants, trees and gardens.

• ADVANTAGES OF DRIP SYSTEM:

Drip Irrigation system has the following advantages:

(a) Drip system provides water to plants drop by drop. So, water is not wasted.

(b) Drip system minimises the use of water in agriculture. So, drip system of irrigation is very useful in those regions where the availability of water is poor.

Lecture 1: Class VIII: SCIENCE: CROPS AND ITS MANAGEMENT (CBSE)- 1

CLASS VIII   |    SCIENCE    |    CHAPTER 1

      Notes prepared by Subhankar Karmakar

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Chapter: 1

• CROP PRODUCTION AND MANAGEMENT

CROP:  When the same kind of plants are grown in the fields on a large scale to obtain foods like cereals (wheat, rice, maize), pulses, vegetables and fruits, etc., it is called a crop.

(i) Cereals: Wheat, Paddy, Maize, Millet

(ii) Pulses: Gram, Peas, Beans

(iii) Oil Seeds: Mustard, Groundnut

(iv) Vegetables: Tomato, Cabbage, Spinach

(v) Fruits: Banana, Grapes, Guava, Mango

• TYPES OF CROPS:

All the crops are categorised into two main groups:

1. KHARIF CROPS: The crops are sown in the rainy season (from June to September) are called Kharif crops. Some of the examples of Kharif crops are: Paddy, Maize, Millet, Soyabean, Groundnut, and Cotton.
2.  RABI CROPS: The crops grown in the winter season (from October to March) are called Rabi crops. Some of the examples of Rabi crops are: Wheat, Gram, peas, Mustard and Linseed.

• AGRICULTURE: 

The growing of plants or crops in the fields for obtaining food ( like wheat, rice etc) is called agriculture.

• BASIC PRACTICES OF CROP PRODUCTION

The various tasks performed by a farmer to produce a good crop are called agricultural practices.

• 1. Preparation of soil,
• 2. Sowing,
• 3. Adding manure and fertilisers,
• 4. Irrigation,
• 5. Removal of weeds,
• 6. Harvesting and
• 7. Storage of food grains.

Sometimes another practice called Rotation of crops is also undertaken to improve soil fertility and to increase crop yield.

• 1. PREPARATION OF SOIL:

The soil is prepared for sowing the seeds of the crop by 

(i) ploughing (ii) levelling and (iii) manuring.

• (i) PLOUGHING: 

The process of loosening and turning the soil is called ploughing or tilling. 

• (ii) LEVELLING: 

The ploughed soil is levelled by pressing it with a wooden leveller so that the top soil is not blown away by wind or drained off by water and thus soil erosion is prevented.

• (iii) MANURING: 

Manuring means adding manure to the soil. It is done to increase the fertility of the soil before seeds are sown into it. 

Prepared by: Subhankar Karmakar 

• AGRICULTURAL IMPLEMENTS:

(i) PLOUGH: 

It is a large agricultural implement which is used for ploughing the soil and it is made of wood.

                       

 

.                             A wooden plough

The wooden plough consists of a long log of wood which is called plough shaft. There is a handle at one end of the ploughshaft. Below the handle is a strong triangular iron strip called ploughshare. The other end of ploughshaft can be attached to a wooden beam which is fixed at right angles to the ploughshaft. 

(ii) HOE:

Hoe is an agricultural implement or tool which is used for removing weeds, and loosening and turning the soil. It consists of a long rod of wood or iron. There is a handle at one end of the hoe. A strong, broad and bent plate of iron is fixed below the handle and acts like a blade. The other end of hoe has a beam which is put on the neck of bullocks.

Prepared by: Subhankar Karmakar 

(iii) CULTIVATOR:

The cultivator is a tractor driven agricultural implement which is used for loosening and turning the soil in the fields quickly. A cultivator has many ploughshares which can dig into a considerable area of soil at the same time, loosen it and turn it. Due to this, many fields can be ploughed in a short time by using a cultivator.

• 2. SOWING:

The process of scattering seeds or putting seeds in the ground soil for growing the crop plants is called sowing. It is the most important part of crop production.

(i) SELECTION OF SEEDS: Good quality seeds are clean and healthy seeds free from infection and diseases and which will give him yield of food grains.

(ii) METHODS OF SOWING SEEDS: There are two methods of sowing the seeds in the soil. These are

(a) Sowing by hand, and

(b) Sowing with a seed drill.

Prepared by: Subhankar Karmakar

(iii) PRECAUTIONS FOR SOWING SEEDS:

a) The seeds should be sown at right depth in the soil suitable for germination.

b) The seeds should be sown at right intervals or spacings.

c) The seeds should not be sown is dry soil.

d) The seeds should not be sown in a highly wet soil.

(iv) ADVANTAGES OF SOWING WITH A SEED DRILL:

a) By using a seed drill for sowing, the seeds are sown at correct depth and correct intervals.

b) The seeds sown with a seed drill are in regular rows.

c) When the seeds are sown in furrows by a seed drill, the seeds get covered by soil and hence these seeds can not be picked up and eaten by birds. This prevents damaged by birds. 

d) Sowing by using a tractor driven seed drill saves time and labour.

Prepared by: Subhankar Karmakar

(v) TRANSPLANTATION:

The process of transferring the seedlings from the nursery to the main field by hand is called transplantation or transplanting.

The Advantages of Transplantation:

a) It helps us to select the better and healthy seedlings for the cultivation by rejecting the damaged seedlings.

b) It allows better penetration of the roots in the soil.

c) It promotes better development of the shoot system of plants.

The practice of transplantation is used in the cultivation of Paddy (rice) crop and in the cultivation of many vegetables like tomatoes and chillies.

Prepared by: Subhankar Karmakar

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HOME TASKS:

1. What are crops? Give some examples.

2. Classify crops with suitable examples.

3. What are Kharif crops? Give examples.

4. What are Rabi crops? Give examples.

5. Which types of crops are also known as summer crops? 

6. What are the basic practices of crop production? 

7. What are agricultural practices? 

8. What are steps to prepare the soil for cultivation?

9. What are ploughing or tilling?

10. What do you understand by the term "manuring"?

11. Describe a plough with a neat sketch.

12. Describe a hoe with a neat sketch.

13. What are agricultural implements?

14. What is a cultivator?

15. What do you understand by " sowing"?

16. What type of seeds are selected for sowing?

17. What are the methods of sowing? 

18. Describe the precautions taken for sowing seeds.

19. Describe the Advantages of sowing with a seed drill.

20. What is transplantation?  Describe its advantages.

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