01.Matter in Our Surroundings11
02.Is Matter Around Us Pure11
03.Atoms and Molecules7
04.Structure of The Atom7
05.Cell - Fundamental Unit of Life11
07.Diversity in Living Organisms8
09.Force and Newtons Laws of Motion12
11.Work and Energy7
13.Why do We Fall Ill7
15.Improvements in Food Resources7
Chapter Notes – Improvements in Food Resources
Improvement in Food Resources
Food is one of the basic needs for all living organisms. Food provides nutrients like carbohydrates, fats, protein, vitamins and minerals.
Sources of food: Agriculture & animal husbandry (livestock).
Problem: India is an agriculture oriented country but still lack of food due to growing population.
- Increase efficiency of production.
- Access of food to people who live in food deserts (urban neighborhoods and rural towns).
- People should have enough money to buy food.
Green Revolution is a programme introduced in many poor countries to increase food production by use of modern technology, proper irrigation, improved seeds, etc.
White Revolution is a programme introduced in India to increase production of milk in India. This programme made India self – sufficient m production of milk.
Similarly Blue Revolution was introduced to enhance fish production and Yellow Revolution was introduced to increase oil production.
Types of Crops
Cereals (wheat, Rice, Maize, Millet, Sorghum) provide us carbohydrates.
Pulse (gram, pea, black gram, green gram, pigeon pea, lentil) provide us proteins.
Oil Seeds (soya bean, ground nut sesame, castor, mustard, linseed, sunflower) provide us fats.
Vegetables, spices, fruits provide us vitamins & minerals.
Fodder crop (berseem, oats, sudan grass are raised as food for the livestock are called as fodder crops.
Different crops require different conditions (temp, moisture, etc.), different Photo – periods (duration of sunlight) for their growth and completing life cycle.
There are following two distinct season crops:
- June to October (Rainy season).
- Monsoon requires more water.
- Paddy, soyabean, pigeon pea, maize, black gram, green gram and rice are kharif season crops.
- Nov. to April.
- Requires less water.
- Wheat, gram, peas, mustard and linseed are rabi season crops.
Improvement in Crop Yield
Yield increases when production increases from same amount of land in same period of time.
Approaches which enhance the crop yield are as following:
- Crop Variety Improvement
- Crop Production Improvement
- Crop Protection Improvement
- Crop Variety Improvement
Some of the factors by which variety improvement can be done, are:
- Good & Healthy Seeds.
- Hybridization technology: It is the process of cross – breeding two different varieties of crops to produce a new variety with good properties of both the crops.
- Genetic Improvement: In genetic improvement, genes of a crop are modified so that desired properties are retained and undesired properties are suppressed.
Properties to be possessed by improved seeds:
- Should give high yield.
- Improved Quality: Should give more nutrients like carbohydrates, proteins etc.
- Biotic Resistance: Resistance to diseases due to living micro – organisms, insects .
- Abiotic Resistance: Resistance to problems due to non – living things
like drought, heat, heat, cold, frost, water logging, salinity (excess salt).
- Less Maturity Duration: Short duration crops require less costing and more rounds of crop.
- Wider Adaptability: Crops which can grow in different conditions, will help in setting high production.
- Desired Agronomic Traits: Crops which contain desired agronomic traits (height, branching, leafs), sets high production.
- Crop Production Improvement
It involves different practices carried out by farmer to achieve higher standards of crop production.
1. Nutrient Management
3. Cropping Patterns
Like other organisms, plants also require some elements for their growth. These elements are called Nutrients.
Macronutrients: Macronutrients are the nutrients required by plants in large amount.
Micronutrients are the nutrients required by small plants in small amount.
Harmful effects of lack of nutrients:
- No proper growth.
- Low resistance to diseases.
- No proper fruits and flowers.
Manure & Fertilizer
Plant nutrients and organic matter in the soil can be increased by adding manures and fertilizers to the soil.
It is defined as the decomposition of animal excreta and plant waste. Manure mainly contains organic matter and also some nutrients in small amount. Based on the biological material used, manures are of three types.
- Compost: Animal excreta (like cow dung etc.), kitchen waste, plant remains, waste wood, etc are left in pit for long time. They decompose slowly to form compost. This compost is used as manure. This process is called composting.
- Vermi Compost: To make the decomposition process fast, earthworms are left in the pit. Earthworms eat up the waste and excrete organic matter as there excreta. The compost thus formed is called vermi – compost. This process is vermin – compositing
- .Green Manure:
Fast growing plants like sun hemp, guar are grown. They are then mulched into the soil by ploughing. They decay to form organic matter. After sometime, the main plants are grown. Remains of the old plant enrich the soil with nitrogen and phosphorus.
How manure helps?
- It provides lots of organic matter which makes soil porous.
- It increases soil fertility in general.
- It provides some nutrients in small amounts.
- As it is made from waste products, so environment is cleaned.
Fertilizers are chemicals manufactured in factories. They are chemicals highly rich in nutrients like nitrogen, phosphorus and potassium.
They provide large amount of nutrients and thus ensure better growth of plants.
Disadvantages of fertilizers:
1. Fertilizers beings chemicals can harm the micro – organism and insects in soil.
2. Fertilizers do not provide much organic matter.
3. Excessive use of fertilizers for a long period of time can damage soil fertility.
4. If excessive irrigation is done, some fertilizers can flow with excess water to water bodies. As fertilizers are chemicals, they will cause water pollution.
|Easily made using animal & plant waste||Made in factories in well defined way|
|No harmful effect as fully natural.||Side effects as it is a chemical.|
|Provides mainly organic matter.||Provides mainly nutrients.|
|Good for long term soil fertility||Not good for long term soil fertility if used in excessive amount.|
|Not as effective as fertilizers.||Very effective in obtaining fast result|
We cannot depend on rain for water as it is not fully reliable. A proper irrigation system will ensure timely and adequate water to crops. This will lead to more yield.
Some most commonly used irrigation systems:
- Wells: These are constructed in the region where enough ground water in available. They are of two types:
Dug Well: In the dug wells, water is collected by bullock-operated devices or by pumps. This method is cheap.
Tube Well: It makes very deep underground water available for irrigation. Motor pump is used to lift water. This method is required high cost.
Man- made water channels originating from rivers or water – reservoirs. They are specifically made to take water to various agricultural plots.
- River Lift System
In this system water is directly taken from rivers through pumps. This system is useful for irrigation in areas close to river.
Tanks are small storage reservoirs which is used to store the rain water.
- Rain Water Harvesting
Rain water harvesting is accumulation of rain water in tanks for later use. This also prevents soil erosion. Soil erosion is unwanted How of top layer of soil with flowing water. This method is required high cost.
Different patterns are used to maximize the production from crop field.
1. Mixed Cropping 2. Inter Cropping 3. Crop Rotation
- Mixed Cropping: In this pattern, seeds of two or more crops are mixed and spread in fields. Both the crops grow together.
Examples: wheat and gram, wheat and mustard, groundnut and sunflower.
How crops are chosen?
- Should require similar environmental conditions like rain, temperature for growth.
- Should require different nutrients so that all nutrients of soil are used.
Advantage: Low risk. If one crop fails, others may still survive.
- Inter Cropping: It is the advanced form of mixed cropping. Two or more crops are grown on the same field in a definite pattern. Few rows of one followed by few rows of other.
Examples: soybean + maize, finger millet (bajra) +cowpea (lobia)
How crops are chosen?
- Should require similar environmental conditions like rain, temp. for growth.
- Should require different nutrients so that all nutients of soil are used.
- Low risk. If one crop fails, others may still survive.
- Disease cannot spread from one row to other.
- Crop Rotation: Crop rotation is policy of growing different crops one after another on the same filed.
If same crop is grown again and again on the same field, same nutrients are extracted from soil again and again. So we should choose different crops so that all nutrients of soil are used.
How crops are chosen?
- Environmental conditions
- Nutrients required by crops.
- Soil fertility is maintained.
- Less use of fertilizers.
- High yield.
- Crop Protection Improvement
When the crop is in the field, it needs protection against weeds, insect pests and other diseases. Following methods are used to control these problems.
- Pest Control during Growth 2. Storage of Grains
Pest Control during Growth
Pest is any destructive organism which can destroy or harm crops or products obtained from them.
Pests are of many types:
- Weeds: Weeds are unwanted plants in the cultivated field like xanthium, parthenium, cyperinus rotundus.
They compete with desired crops for food, space and light. Therefore desired crops get less nutrients and are adversely affected.
- Insects: Insects can harm plants in following ways :
- They can cut roots, stems and leaves of plants.
- They can get into fruits, flowers and steam of plants destroying them.
- They can suck food and water from plant bodies.
- Pathogens: Any organism that can produce disease is called pathogens. Example; bacteria, virus, fungi.
Plants can get these organisms from soil, air or water. Diseases caused by these can spread in all crops on the field and destroy the entire cultivation.
Various methods are used to control weeds, insect etc.
- Killing Pests
Various types of pesticides are spread on plants to kill different pests. These are toxic chemicals. Herbicides kill weeds. Insecticides kill insects. Fungicides kill fungi.
Disadvantages of using pesticides:
- Toxic to many useful plants and animals.
- Weed Control
Weed Control involves precautionary measures to avoid weed growth.
- Manual removal of weeds.
- Seed bed preparation: Fields are ploughed deep. Thus weed seeds come on top and germinate in few days. Then they can be removed before planting actual crops.
- Crop Rotation: Some crops destroy weeds in fields. Such crops included in crop rotation.
- Proper Sowing Time: Warm and humid climate not favourable.
- Inter Cropping: Due to presence of multiple crops, environmental resources are used more efficiently. Thus very little resources are left for growth of weeds.
Storage of Grains
For getting seasonal foods throughout of the year, they are stored in safe storage. But during storage of grains, they can destroy and waste by various means.
- Biotic problems: Due to living organisms like insects, birds, mites, bacteria, fungi.
- Abiotic problems: Due to non – living factors moisture, inappropriate temperature etc.
These factors affect quality degradation, loss in weight, change in colour, loss of germinability.
- Proper cleaning of product and warehouse.
- Proper drying of products before storing.
- Fumigation (drugs which form toxic fumes which can kill pests) to kill pests and insects.
Use of fertilizers and pesticides has their own disadvantages. They cause pollution, damage soil fertility in long run. Grains, fruits, vegetables obtained may contain harmful chemical in small amount.
Organic farming is farming system with no or very little use of chemicals like fertilizers and pesticides.
Process of Organic Farming
- Use of manure.
- Use of bio fertilizers: blue – green algae (organism). They fix nitrogen from atmosphere to soil. Some micro – organism can also kill pests. They are intentionally put in soil to kill pests. They act as bio fertilizers.
- Use of bio pesticides: Neem and turmeric can kill some pests.
- Weed & Pest control systems are used. So that use of pesticides is not required.
- Use different cropping pattern like mixed Cropping, intercropping and crop Rotation.
Animal husbandry is the scientific management of domestic animals in an efficient manner to obtain food and other useful products from them.
Purpose of Cattle Farming:
- For getting milk.
- Ploughing fields.
- Bull Cart for transportation.
Types of Cattle:
- Cow (Bos indicus).
- Buffalo (Bos bubalis).
Milch Animals: These includes milk producing animals(female cattle).
Draught Animals: Those animals which do not produce milk and used for agricultural work.
Female cattle give milk after birth of calf (baby). The time duration for which she gives milk is called lactation period. Typical under a year.
How to increase lactation period?
- Cross breeding: Cross breeds are obtained by hybridization or by crossing animals of different species. The offsprings produced are called “Hybrids”. Hybrids show good characters of both the parents like high lactation period, high resistance to diseases.
- Proper diet.
Care of Cattle
– Roofed shelter with good ventilation for protection from rain, heat and cold.
– Regular brushing of skin of cattle.
– Sloping floor of shelter for avoiding water – logging.
– Roughage mainly containing fibre.
– Concentrates containing proteins.
– Food containing micronutrients (Vitamins and minerals) for enhanced milk production.
Proper food is required for good health and special diet should be given during lactation period.
Disease can cause death and reduce milk, production.
- Parasites are small organisms living inside or outside the body of another organism (host). They derive food from body of host.
- External parasites on skin of cattle cause skin diseases
- Internal parasites like worms cause stomach and intestine problems and flukes cause liver problems.
- Bacteria, virus cause infectious diseases (diseases that can be easily transmitted from one to another).
Vaccination is given against major diseases.
Poultry Farming is done for eggs and meat. Both provide protein to our diet.
Broilers: Birds grown for obtaining meat are called broilers. They can be used after 6-8 weeks from their birth.
Layers: Birds grown for obtaining egg are called layers. They can be used after 20 weeks when sexual maturity has been attempt to lay eggs.
Most of the broilers & layers are cross – breed.
Breeding is done to enhance following properties in hens :
- More and better quality chicks.
- Low maintenance.
- Breeding is done to produce dwarf broilers (meat – giving birds). Feeding cost is the biggest expense in poultry farms. Dwarf broilers need less food and can reduce cost by 30 %. Also they can tolerate more heat.
Management Practices in Poultry farms:
- Proper diet: Layers eat mostly fibre diet. Broilers need diet rich in protein, fat and vitamin A and K.
- Maintenance of proper temperature.
- Hygienic environment and proper sanitation.
- Regular spraying of disinfectants to kill bacteria, virus, fungi and parasites which can otherwise cause diseases.
- Controlling canvass quality. Canvass quality refers to ratio of bone to flesh in chicken.
- Avoid mortality.
- Providing adequate space to birds. This is important for their proper growth.
Fish production is a great source of protein to our diet.
Fish production is of two types:
- Finned Fish Production / True Fish Production: Production and management of cartilaginous and bony fishes such as pomphret, tuna ,cod, catla, prawns, rohu, mrigal, etc.
- Unfinned Fish Production : Production of shellfish such as prawns, mollusks.
Depending on the mode of obtaining fishes, fishing are of two types:
- Capture Fishing: Naturally living fishes in various water bodies are captured.
- Culture Fishing: Fishes of desired variety are cultivated in confined areas with utmost care to get maximum yield. This is also called aquaculture. Aquaculture can be done in oceans, rivers, lakes, ponds, etc. When it is done is oceans, it is called mariculture.
Marine fishing includes fish production in ponds, rivers, lakes, reservoirs.
India has huge coastline of 7500 km. So it is natural for India to have a large marine fishing industry.
Popular marine fishes include pomphret, mackerel, tuna, sardines, Bombay duck. Some costly fishes found in sea like mullets, prawns, mussels, seaweed, oysters.
Using satellites, regions of high fish population in sea can be found. Echo – sounders are also used.
It includes fish production in fresh water (for ex. ponds, rivers, lakes, reservoirs) and brackish water (for ex. Estuaries, lagoons).
This type of fishing gives lower yield compared to marine fishing. Capture & culture fish farming, both are done in such water bodies.
Composite Fish Culture
– 5 to 6 varieties in a single fishpond.
– They are selected so that they do not compete for food. They should have different food requirements.
Examples: Catla: feeds in the upper part water
Rohu: feeds in middle part of water
Mrigals, Common Carps: feeds at bottom
Advantage: More yield.
Problems: Many fishes lay eggs during monsoons only, due to which number of fishes will not grow fast. So hormonal stimulation is used, using this fishes can be made to reproduce anytime.
Bee – Keeping
It is the practice of keeping, caring & management of honeybees on a large scale for obtaining honey & wax.
Many farmers use bee – keeping for additional small income. Also there are big farms called apiaries/ bee farms.
Some common Indian varieties of bees include apis carana indica (Indian bee), dorsata (rock bee), florae(little bee).
One Italian variety mellifera is also used in India for commercial large scale production because of its following advantage:
1. High honey collection capacity.
2. They reproduce fast.
3. They sting less.
4. They stay in a beehive for long.