Energy Flow Through an Ecosystem

1
Energy Flow Through an Ecosystem

• Food Chains, Food Webs, Energy Pyramids

2

• Begins with the SUN
• Photosynthesis

6CO2 6H2O sunlight chlorophyll ?C6H12O6
6O2

• OR
• Begins with CHEMICALS
• Chemosynthesis

3
Organisms that can make their own food from
inorganic molecules are called PRODUCERS.
4
Producers use most of the energy they make for
themselves.
The energy that is not used by producers can be
passed on to organisms that cannot make their own
energy.
5
Organisms that cannot make their own energy are
called CONSUMERS.
6
Consumers that eat producers to get energy
Organisms that cannot make their own energy are
called CONSUMERS.

• Are first order or primary consumers
• Are herbivores (plant-eaters)

7
Most of the energy the primary consumer gets from
the producer is used by the consumer.
Some of the energy moves into the atmosphere as
heat.
8
Some energy in the primary consumer is not lost
to the atmosphere or used by the consumer
itself.This energy is available for another
consumer.
9
A consumer that eats another consumer for energy

• Is called a secondary or second order consumer
• May be a carnivore or a onmivore
• May be a predator
• May be a scavenger

10
Most of the energy the secondary consumer gets
from the primary consumer is used by the
secondary consumer.
Some of the energy is lost as heat, but some
energy is stored and can passed on to another
consumer.
11
Consumers that eat producers other consumers

• Are called omnivores
• Omnivores eat plants and animals

12
The transfer of energy from sun to producer to
primary consumer to secondary consumer to
tertiary consumer can be shown in a FOOD
CHAIN.Each step in a food chain is a trophic
level
13
Food Webs

• Are interconnected food chains
• They show the feeding relationships in an
  ecosystem
• It is harder to following the tropic levels in a
  food web

14
Another way of showing the transfer of energy in
an ecosystem is theENERGY PYRAMID.
15
Energy pyramids show

• That the amount of available energy decreases
  down the food chain
• It takes a large number of producers to support a
  small number of primary consumers
• It takes a large number of primary consumers to
  support a small number of secondary consumers

16
Fourth Tropic level
Third Tropic level
Second Tropic level
First Tropic level
17
Biological Magnification

• Increase in concentration of a pollutant at
  higher trophic levels.
• Pollutants can become more concentrated in
  tissues of higher level consumers over time.
• Metals (like mercury) and DDT (a pesticide) are
  both pollutants that are very dangerous through
  biological magnification.

18
Biological Magnification