Improvement in Food Resources Class 9 Science Chapter 15 NCERT Notes

Natural Resources Short Notes || Class 9 Science

Introduction

All living organisms need food for energy, growth, and survival. We obtain food from plants and animals through agriculture and animal husbandry. As the population increases, it’s crucial to improve food resources not only in terms of quantity but also in quality. This involves increasing crop yields and improving crop varieties.

Green Revolution   

 The Green Revolution in India involved the introduction of high-yielding variety (HYV) seeds, chemical fertilizers, pesticides, improved irrigation, and mechanization of agriculture. These changes led to a significant increase in food grain production, making India self-sufficient in food.

White Revolution
 
The White Revolution, also known as Operation Flood, was a significant movement in India aimed at increasing milk production. It transformed India into one of the largest producers of milk and dairy products in the world. 

Improvement in Crop Yields
  1. Varietal Improvement: Developing high-yielding and disease-resistant crop varieties.
  2. Nutrient Management: Using fertilizers and organic manures to provide essential nutrients to crops.
  3. Irrigation: Ensuring adequate water supply through efficient irrigation methods.
  4. Cropping Patterns: Implementing practices like mixed cropping, intercropping, and crop rotation to maintain soil fertility and reduce pest infestations.
  5. Pest and Weed Control: Using chemical and biological methods to protect crops from pests and weeds. 

Crop Season
 

The main seasons for growing crops are:

  1. Kharif Season: This season occurs during the monsoon, typically from June to September. Kharif crops are sown with the onset of the first rains and harvested in the autumn. Common Kharif crops include rice, maize, cotton, and pulses.

  2. Rabi Season: The Rabi season follows the Kharif season, occurring from October to March. Rabi crops are sown in the winter and harvested in the spring. Key Rabi crops include wheat, barley, peas, and mustard.

  3. Zaid Season: This is a short season that occurs between the Kharif and Rabi seasons, usually from March to June. Zaid crops are grown in the warmer months and include crops like cucumbers, melons, and vegetables.

Crop Variety Improvement
  1. Hybridization: Crossing different varieties of plants to produce a new variety with desirable traits like higher yield, disease resistance, and better quality.
  2. Genetic Modification: Incorporating genes with desirable traits into crops to improve their quality and quantity.
  3. Selection: Choosing the best plants with desirable characteristics from a population to be used for further breeding.
  4. Introduction of New Varieties: Bringing in new crop varieties from different regions to improve local crop production.
 
Crop Production Management
 
It involves different practices carried out by farmers to achieve higher standards of crop production.

• The different practices are:

(i) Nutrient management
(ii) Irrigation
(iii) Cropping patterns

(i) Nutrient Management: Like other organisms, plants also require some elements for their growth. These elements are called nutrients.
 
Manure
 

Manure is organic matter, primarily derived from animal waste, that is used to fertilize soil. It is rich in nutrients that are essential for plant growth, including nitrogen, phosphorus, and potassium.

Types of Manure:

  1. Farmyard Manure (FYM): Composed of a mixture of animal dung, urine, and bedding materials such as straw. It improves soil structure and fertility.

  2. Composting: A process that involves the decomposition of organic materials such as vegetable scraps, leaves, and other plant materials, creating nutrient-rich compost.

  3. Green Manure: Plants that are grown specifically to improve soil fertility when they are plowed back into the soil.

Fertilizers
 

Fertilizers are chemical substances that are added to soil or plants to supply essential nutrients that plants need for growth and development. They can be either natural (organic) or synthetic (inorganic).

Types of Fertilizers:

  1. Organic Fertilizers:

    • Derived from natural sources such as plants, animals, and mineral ores.
    • Examples include manure, compost, and bone meal.
    • They improve soil structure and increase biodiversity in the soil.

  2. Inorganic (Chemical) Fertilizers:

    • Manufactured through industrial processes and contain specific nutrients in concentrated forms.
    • Common types include:
      • Nitrogenous Fertilizers: E.g., urea, ammonium sulfate - primarily supply nitrogen.
      • Phosphatic Fertilizers: E.g., superphosphate - primarily supply phosphorus.
      • Potassic Fertilizers: E.g., potassium chloride - primarily supply potassium.
Irrigation
  • Irrigation is the process of artificially supplying water to crops to meet their water requirements.
  • Crops need water for growth, development, and other functions.
  • Various sources of water for irrigation include wells, ponds, lakes, canals, tube-wells, and dams.
 
Crop Patterns
 

Crop patterns are the arrangement of various crops grown in a specific region. They are influenced by factors such as climate, soil type, water availability, and farming techniques.

Types of Crop Patterns:

  1. Monoculture:

    • The practice of growing a single crop species over a large area for consecutive seasons.
    • This can lead to increased productivity but may also result in nutrient depletion and higher pest risks.

  2. Crop Rotation:

    • The practice of alternating different crops in the same field across different seasons.
    • It helps in managing soil fertility, reducing pests and diseases, and improving crop yields.

  3. Intercropping:

    • The cultivation of two or more crops simultaneously on the same piece of land.
    • It can enhance biodiversity, optimize resource use, and improve overall crop productivity.

  4. Mixed Cropping:

    • Growing two or more crops together without a distinct row arrangement.
    • This can help in risk management as if one crop fails, the other may succeed.
Crop Protection Improvement
 
To protect crops against diseases caused organisms and other harming factors
is called crop protection.

• Methods used to control the problems:

(i) Pest control during growth
(ii) Storage of grains
 
Animal Husbandry
 
Animal husbandry refers to the branch of agriculture concerned with the breeding and care of animals raised for food, fiber, or labor. It includes the management of livestock for dairy production, meat, wool, and other animal products.

Types of Animals in Animal Husbandry:

  1. Dairy Cattle: Bred mainly for milk production (e.g., Jersey, Holstein).
  2. Beef Cattle: Raised for meat production (e.g., Angus, Hereford).
  3. Poultry: Chickens are raised for eggs and meat (e.g., broilers and layers).
  4. Sheep: Raised for meat (mutton) and wool (e.g., Merino).
  5. Goats: Bred for meat (chevon) and milk (e.g., Saanen, Boer).
  6. Pigs: Raised for pork production (e.g., Yorkshire, Landrace).
Fish Production
  • Fish Production:
    • Capture Fishery: Harvesting naturally occurring fish from lakes, rivers, and oceans.
    • Culture Fishery: Controlled cultivation of fish in water bodies (pisciculture).
    • Inland Fishery: Freshwater fish farming (e.g., Rohu, Catla).
    • Marine Fishery: Coastal and deep-sea fishing (e.g., sardines, prawns).
 
Bee - keeping
 
Bee-keeping is a sustainable agricultural practice that not only contributes to the economy through honey and beeswax production but also supports crop pollination, benefiting the ecosystem.

Types of Bees:
  • Worker Bees: Females that do not reproduce but perform various tasks like foraging, hive maintenance, and caring for the queen and larvae.
  • Drones: Male bees whose primary role is to mate with the queen.
  • Queen Bee: The reproductive female responsible for laying eggs in the hive.
Bee-keeping Methods:
  • Beekeepers manage hives and ensure bees are healthy, have adequate food sources, and are protected from diseases and pests.