How farming has changed to allow increased yeilds.

By: Panhya, Macnel, Net9B

How it has changed:Fertilizers are being used more.

• To increase the amount of nutrients available in the soil which are essentials to the growth of plants.

• It can cause Eutrophication.Pesticides are being used more.

• They are substances that prevents or destroys pests.

• Some of them are chemical substances which can travel up the food chain and cause negative effects to it.

How it has changed:Larger fields (Hedge rows were removed) Larger fields allow farmer to work more freely. The size of machineries these days can only be used in

large sized fields. Removing hedgerows literally leaves more space for

the crops and save time and money on hedge maintenance.

More machinery are being used, less labor intensive.• It can work harder and faster than men’s labor,

therefore it increases the speed of farmers for getting their crops.

Through out time farming has changed and brought us positive effects. (Faster growth, more products, etc.) But most people forgets about the negative effects that was as well brought. And some people choose not to care about the negatives at all to benefit their own goods.

Negative of FertilizersEutrophication

Fertilizers that are used in farming run-off into the river and cause the increase of nutrient level.

This causes phytoplankton to grow and reproduce more rapidly, resulting in algal blooms.

Then the algae blocks out the light, killing plants below the surface of the lake.

The decomposing plants reduce the amount of oxygen in the water.

The decrease in oxygen causes fish and other animals to die.

Negative of PesticidesPesticides are chemical substances, and when the

chemical travels up the food chain and build up in consumers(bioaccumulation, more on this on furthur slide), it can stop the food chain from its own cycle. (Eg. Caterpillars eat crops but farmers use chemical pesticides, after the caterpillars ate the crops it got the chemical inside it. Birds eat caterpillar, it ate the chemical inside it. Then the bird will end up dead. And if there is no birds then predator that eat birds will have nothing to eat, that can lead to serious problem such as extinction.)

Negatives of Removing HedgerowsSoil Erosion-High winds from precipitation

can erode soils if hedges are not there to keep the soil in place. (More on this in further slide)

It can lead to a decrease in soil fertility.Livestock are left without shelter from harsh

weather, crops can be damaged from strong winds and rains too.

Loss of biodiversity, hedges are important habitat for lots of animals.

Soil ErosionSoil erosion is loss of soil from land.The process of soil erosion usually occurs

slowly, the accelerate erosion is caused by human impact on land use, such as poor farming practice.

Soil erosion is common in areas with steep slopes, where trees have been cut down, in droughts when crops and other vegetation grows poorly and in rural areas which are overpopulated.

Causes of Soil ErosionDeforestationPloughingMonocultureRemoval of hedgesOvergrazing

How to limit soil erosion?• Terracing•Contour ploughing•Shelter belts•Strip farming•Magic stones

Bioaccumulation (The effect of pesticides)

Bioaccumulation is the increase in concentration of a substance in living organisms as they take in contaminated air, water, or food.

As bigger animals eat smaller animals, the level of contamination in the food is added to the level of contamination already in their body.

Bioaccumulation is a problem in the north because of higher concentrations of toxic pollution.

Also, northern animals have a lot of fat to keep them warm, toxins accumulate mostly in fat .

GMOs (Genetically Modified Organisms)They are plants, animals, or organisms that

were not naturally made. They are organisms that contains DNA from

different species mixed with their own.

The advantage of using GMO INCREASE PLANTS RESISTANCE TO PEST. Saves the use of

toxic chemicals. GM crops can be made resistant to the pests, so pesticides do not need to be sprayed on them. This is also better on the environment.

DECREASE THE AMOUNT OF WATER PLANTS/CROPS NEED TO GROW.

It can make products more attractive to consumers my changing the appearance and the colors.

It creates faster growth and more products.The danger of using GMOs

•Risk of disease• For example if you mix a cat’s DNA with the plant,

then that plant is being used to make cat’s food. When the cat eat that food, there are chances that a cat can get a disease. Organisims often get diseases from the same DNA.

 

The End (:

B GradeA good power point presentation. Good

general knowledge. It could be improved by using specific case studies.