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Sources of food - Coggle Diagram

- - - - Burning large areas of forest in neighbouring countries
      - Poor visibility
        
        Particles reduce amount of sunlight that reaches us
      - Breathing difficulties and eye irritation
        
        particles in the haze can cause people with respiratory problems to have breathing difficulties.
        
        it can cause death
        
        People with sensitive eyes may experience irritation of the eyes in a hazy environment
      - higher air temperature
        
        it traps heat in our surroundings and prevents heat from being reflected back into the atmosphere.
    - - When it rains, the tree roots in the forest keep the top soil together.
        
        It prevents the soil from being washed away by the rain
        
        however, when it is cleared, the top soil is exposed to the wind and rain. It can easily wash away.
        
        This cause landslides and destroy lives and properties.
    - - The fire will become uncontrollable due to strong winds and will spread to surrounding forests.
        
        Not small area but the entire forest will be burnt to the ground.
    - - Not only are the forests destroyed but many animals can be injured or killed because their habitats are lost to the fire,
- - - - It decreases the crop yield as there are less nutrients available for crops
  - - - Pesticides
        
        it has chemical substances that is used by farmers to destroy pests
        
        They can also be sprayed onto the plants or crops to prevent attacks by pests
      - Herbicides
        
        these are chemicals used by farmers to prevent or destroy weeds which compete with the crops for nutrients.
        
        it is also called weed killers
        
        they destroy weeds but do not harm crops.
      - Effects
        
        Soil contamination
        
        Pesticides and herbicides can contamination the soil especially of large amounts are used.
        
        Water contamination
        
        Aquatic plants and animals living in the rivers, lakes and ponds will be affected by the contaminated water.
        
        humans and animals that drink from the affected water bodies will also be harmful by the chemicals.
      - Biological controls
        
        Natural enemies
        
        No chemicals used, hence there is no contamination of soil and water
        
        Crops are also not contaminated by chemicals.
        
        It is a good way to remove pests but it may disrupt the food chain when population become too high to control.
- - - - Good seedlings will grow into bigger and better crops.
        
        It has higher nutritional values and are able to survive harsh weather conditions.
    - - hydroponics
        
        a method of growing plants in a special nutrient solution
      - aeroponics
        
        a method of growing plants in a mist of nutrient solution regularly sprayed onto the roots of the plants.
        
        These farms use automation to control the temperature, water and nutrient supplies to ensure optimal plant growth
    - - With the use of intensive farming methods, the food production of these farms has been increased.
    - - animals that grow to larger sizes and at faster rates
        
        ex: sheep for wool
      - Chicken that lay bigger and more eggs
      - Good meat and milk producing cattle
    - - Intensive farming methods
        
        Fish farming
        
        Harvesting of fish using this method is not dependent on weather conditions
        
        Fishes are also fed well and within a short period of time
        
        Fishes are reared in large tanks of water aerated with oxygen
        
        Dairy farm
        
        Milk from cows is expressed through automated machines, making milking easier and faster
        
        Eggs
        
        Eggs are collected by conveyor belts hence reducing the time required to harvest the eggs
      - Traditional methods of farming
        
        Eggs
        
        Eggs laid in nests are manually collected
        
        Dairy farm
        
        Milk is manually expressed into by hand
        
        This can be strenuous and time consuming
        
        Fishing
        
        Fishermen preparing to cast their net into the sea
        
        This can be strenuous, time consuming and weather-dependent
  - - - Farmers can use plant hormones as weed killers, to regulate growth and ripen fruits
        
        Weed killers
        
        Some plant hormones can kill weeds without harming the crops.
        
        It will wither and be destroyed in a short time when sprayed with plant hormones
        
        Ex: The addition of plant hormones to rice and wheat
        
        Resulting in the weeds being destroyed without affecting the crops.
        
        To regulate growth and ripening of fruits
        
        Plant hormones can be used to regulate growth of fruits.
        
        hormones are added to the tomato plants to promote root formation on the stems to increase the number of tomato fruits on the plant
        
        Plant hormones can also be used to regulate the ripening of fruits
        
        The addition of hormones to fruits prevent them from dropping off trees before ripening.
- - - - Ex: insects, mammals...
        
        Like all other living things, plants need food to grow too.
        
        plants are able to make their own food through the process of photosynthesis
    - - Any excess food is stored in the leaves, stem, roots and fruits of the plants.
        
        When animals or eat these part of plants, they absorb the stored energy from the food.
    - - carbon dioxide + water → food + oxygen
    - - The presence of starch is often used as an evidence to show photosynthesis has occurred.
  - - - It must contain the necessary nutrients for healthy growth of the plants
        
        the pH value of the soil also plays an important part in determining healthy plant growth
        
        it can be determined using indicators such as the litmus paper, universal indicator or pH meter
- - - - Fertilisers are substances added to soil to increase the amount of essential nutrients required by the plants.
        
        It helps to improve plant growth and crop yield.
        
        It is non-toxic and does not pose a threat to the environment.
  - - - Contamination is what can damage the environment.
        
        It can contaminate the groundwater (this will affect the quality of drinking water)
      - Negative impact on aquatic life will affect the health of aquatic plants and animals as the chemicals are too toxic for them.
        
        Chemical fertilisers are rich in nutrients such as nitrogen and phosphorus
        
        These nutrients can cause the rapid growth of algae on water surface when washed into water bodies.
        
        It prevents sunlight and oxygen from reaching the aquatic plants and animals living in water bodies.