1. Chapter 9
Biological Productivity
and Energy Flow
Case Study:
Can Enough Food be Produced
for Africa???
How much can we grow???
What will be our Carrying
Capacity?????

2.  The total amt of organic matter in an
ecosystem =
 It increases though growth
Plants, animals and dead are all biomass

3.  Biomass is measured
in
 It increases through
growth.
 This is

4. Chemoautotrophs
 Bacteria that use
inorganic compounds
(like sulfur) to make
their own food and
tissues
The white-ish area is a bacterial
mat feeding on methane from
beneath the ocean floor.
Hydrothermal vents

5. Energy flow
 Ecosystems are all open to energy flow
Energy in food chain heat released
 What is not used is lost (as heat), or stored!!!!

6.  1. kinetic-
 2. potential-
 energy can move back and forth between
the two
 Entropy-is the measure of disorder, wasted
energy - becomes more random, can be
sound or light but is mostly heat, everything
always moves towards entropy

7. The laws of thermodynamics
 1st Law – conservation of energy

8.  2nd Law- entropy increases
 -energy moves to a less organized form
(living cells are holding off the forces of
entropy by channeling energy).

9.  Energy flow is one way!

10. Energy efficiency
 How efficient are orgs at using energy?
 Not very!
 Rule of thumb is:

12. Biomass Pyramid