NCERT Class 9 Science Solutions: Chapter 15 Improvement in Food Resources Part 3

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Q 2 Image Showing Broiler Farms V/S Layers Farm.

Q 2 Image Showing Broiler Farms V/S Layers Farm

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Question 2:

Q. What are the differences between broilers and layers and in their management?

Answer:

Layers are meant for egg production, whereas broilers are meant for poultry meat. Nutritional, environmental, and housing conditions required by broilers are different from those required by egg layers. A broiler chicken, for their proper growth, requires vitamin rich supplements especially vitamin A and K. Also, their diet includes protein rich food and enough fat. They also require extra care and maintenance to increase their survival rate in comparison to egg layers.

Question 1:

Q. How are fish obtained?

Answer:

Fish can be obtained by two ways:

(i) Capture fishing: It is the process of obtaining fish from natural resources.

(ii) Culture fishery: It is the practice of farming fishes. Farming can be done in both freshwater ecosystem (Which includes river water, pond water) and marine ecosystem.

Question 2:

Q. What are the advantages of composite fish culture?

Answer:

An advantage of composite fish culture is that it increases the yield of fish. In a composite fish culture, five or six different species are grown together in a single fish pond. Fishes with different food habits are chosen so that they do not compete for food among themselves, Also, this ensures a complete utilize of food resources in the pond. As a result, the survival rate of fish increases and their yield also increases.

Question 1:

Q. What are the desirable characters of bee varieties suitable for honey production?

Answer:

Bee varieties having the following desirable are suitable for honey production:

(i) They should yield high quantity of honey.

(ii) They should not sting much.

(iii) They should stay in the beehive for long durations.

(iv) They should breed very well.

Question 2:

Q. What is pasturage and how is it related to honey production?

Answer:

Pasturage is the availability of flowers from which bees collect nectar and pollen. It is related to the production of honey as it determines the taste and quantity of honey.

Question 1:

Q. Explain any one method of crop production which ensures high yield.

Answer:

Crop rotation is one of the methods of crop production that ensures high yield. It is the method of growing two or more varieties of crops on the same land in sequential seasons. A crop utilizes some particular nutrients in larger quantities from the soil. Then, if the same crop is grown in subsequent seasons those nutrients will get depleted in the soil. Therefore, crops having different nutrient requirements are rotated. For example, legumes which have nitrogen-fixing bacteria in their root nodules supply the soil with nitrogen. Therefore, these legumes are rotated with nitrogen requiring cereals such as wheat and maize. This method reduces the need of fertilizers, thereby increasing the overall yield of crops.

Question 2:

Q. Why are manures and fertilizers used in fields?

Answer:

Manures and fertilizers are used in fields to enrich the soil with the required nutrients. Manure helps in enriching the soil with organic matter and nutrients. This improves the fertility and structure of the soil. On the other hand, fertilizers ensure a healthy growth and development in plants. They are a good source of nitrogen, phosphorus, and potassium. To get an optimum yield, it is instructed to use a balanced combination of manures and fertilizers in the soil.

Question 3:

Q. What are the advantages of inter-cropping and crop rotation?

Q 3 Image Showing Advantages Of Intercropping.

Q 3 Image Showing Advantages of Intercropping

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Answer:

Inter-cropping and crop rotation both play an important role in increasing the yield of crops. Inter-cropping helps in preventing pests and diseases to spread throughout the field. It also increases soil fertility, whereas crop rotation prevents soil depletion, increases soil fertility, and reduces soil erosion. Both these methods reduce the need for fertilizers. It also helps in controlling weeds and controls the growth of pathogens and pests in crops.