ENERGY PYRAMIDS
What happens to the food you eat?
About 90% is used to fuel your body. Food is converted into energy for your body to function.
10% is converted into your bones, skin, muscles, and organs, This is called your biomass.
This is called the rule of 10%.
It means that every single organism only stores 10% of what is eats as biomass.
HOW DOES THIS AFFECT A FOOD WEB?
If all energy comes from producers, then as it moves up the food chain it eventually runs out!!
About 90% is used to fuel your body. Food is converted into energy for your body to function.
10% is converted into your bones, skin, muscles, and organs, This is called your biomass.
This is called the rule of 10%.
It means that every single organism only stores 10% of what is eats as biomass.
HOW DOES THIS AFFECT A FOOD WEB?
If all energy comes from producers, then as it moves up the food chain it eventually runs out!!
Lets take a look at it in the form of a picture.
Each level of this pyramid is called a TROPHIC LEVEL
Producers are at the base of the pyramid. This is the 1st trophic level
Producers Use 90%, store 10% as biomass.
Primary consumers are at the second trophic level directly above the producers.
Primary Consumers eat producers. They get that 10% of energy stored by the producer.
They Use 90% Store 10%.
This means that 1% of the original energy is re-stored in the bodies of primary consumers.
Secondary consumers are at the third trophic level.
Now that 1% of stored biomass is eaten by secondary consumers.
They Use 90% Store 10%.
What this means is that 0.1% of the energy originally made by the producers is re-stored in the bodies of secondary consumers.
Each level of this pyramid is called a TROPHIC LEVEL
Producers are at the base of the pyramid. This is the 1st trophic level
Producers Use 90%, store 10% as biomass.
Primary consumers are at the second trophic level directly above the producers.
Primary Consumers eat producers. They get that 10% of energy stored by the producer.
They Use 90% Store 10%.
This means that 1% of the original energy is re-stored in the bodies of primary consumers.
Secondary consumers are at the third trophic level.
Now that 1% of stored biomass is eaten by secondary consumers.
They Use 90% Store 10%.
What this means is that 0.1% of the energy originally made by the producers is re-stored in the bodies of secondary consumers.
The amount of energy that is available to each tropic level is 10% of the energy that was available to the tropic level underneath it.
This limits the number of levels that you can have. This also explains why there are many many more plants than top predators.
Lets look at some examples:
1) A prairies has 100, 000, 000 kilocalories of energy available to its producers. A hawk is a secondary consumer and needs 10,000 kilocalories(kcal) to survive. How many hawks can this prairie support?
Lets work it out:
10% becomes biomass of the producers:
100,000,000/10 = 10.000,000 kcal
10% of that becomes biomass of primary consumers
10,000,000/10 = 1.000,000 kcal
1,000,000 kcal is available for secondary consumers
A hawk needs 10,000 kcal.
1,000,000 kcal/10,000 kcal per hawk = 100 hawks can be supported by this prairie.
This limits the number of levels that you can have. This also explains why there are many many more plants than top predators.
Lets look at some examples:
1) A prairies has 100, 000, 000 kilocalories of energy available to its producers. A hawk is a secondary consumer and needs 10,000 kilocalories(kcal) to survive. How many hawks can this prairie support?
Lets work it out:
10% becomes biomass of the producers:
100,000,000/10 = 10.000,000 kcal
10% of that becomes biomass of primary consumers
10,000,000/10 = 1.000,000 kcal
1,000,000 kcal is available for secondary consumers
A hawk needs 10,000 kcal.
1,000,000 kcal/10,000 kcal per hawk = 100 hawks can be supported by this prairie.
ACTIVITY:
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