An Ecological Pyramid is a graphical representation designed to show the biomass or productivity at each trophic level in a given ecosystem.

1. Ecological Pyramids, Food Chain and
Food Web
by: Liwayway Memije-Cruz

2. What is an ecological pyramid?
• a graphical
representation
designed to
show the
biomass or
productivity at
each trophic
level in a
particular
ecosystem.

3. Number Pyramid
• shows the number of
organisms in each trophic
level and does not take
into consideration the
size of the organisms and
over-emphasizes the
importance of small
organisms. In a pyramid
of numbers the higher up
one move, so each
consecutive layer or level
contains fewer organisms
than the level below it.

4. Biomass Pyramid
• shows the total mass of the organisms in each
trophic level.

5. Energy pyramid.
• shows the total amount of
energy present in each
trophic level.
• indicates the loss of energy
from one trophic level to the
next.
• clearly illustrates that the
energy transfer from one
trophic level to the next is
accompanied by a decrease
due to waste and the
conversion of potential
energy into kinetic energy
and heat energy.

6. Food Chain
• the feeding of one
organism upon another in a
sequence of food
transfers .
• the chain of transfer of
energy from one organism
to another.
• the passage of energy from
one tropic level to the next
as a result of one organism
consuming another.
• simply who eats whom.

7. GRAZING FOOD CHAIN
• one which goes from green plants to grazing
herbivores and finally to carnivores.

8. DETRITUS FOOD CHAIN
• one, which goes from dead organic matter to
microorganisms and then to detritus feeding
organisms.

9. Food Web
• an interlinked food chains.

10. Food Web
• an interlinked food chains.