Warm Up: Write a paragraph that
summarizes primary productivity
and secondary productivity. Explain
how you would calculate each.
Energy Dynamics Lab Ojective
• To investigate the net primary productivity of
mung beans and the net secondary
productivity of pill bugs
Part 1: Mung Beans
• The mung beans were massed and
determined to have an average mass of 0.076
g
• They were sprouted and allowed to grow for 7
days
• We will now determine the primary
productivity of the mung bean
Materials
• Mung bean plants, scales, dehydrator
• 1. Write a detailed procedure of how you
would determine the net productivity of the
mung bean plant
– Include any information (constants) you would
need
– Include specific calculations you would perform to
get your final answer
Part 1: Mung Beans
• Obtain 2 different plants
• Mass each to get the ‘live wet mass’ record
this on your data sheet
• Place in dehydrator on labeled paper towel
• Mass after dehydration to get ‘dried mass’
• Begin calculations for primary productivity
Part 2: Pill Bugs
• Using pill bugs and potatoes you will now
determine the secondary productivity of pill
bugs in different environments
• 2. Write a detailed procedure of how you
would determine the secondary productivity
– Explain what constants or information you will
need
– Explain any calculations you will make to get your
final answer
Part 2: Pill Bugs
• Mass 5 pill bugs and your potato slices
Productivity Review
• Primary: Indirectly measure by determining
the change in biomass of plants for a specific
amount of time
– Dry biomass (why?)
• Secondary: Indirectly measure by determining
the amount of chemical energy in food is
converted to new biomass in a given amount
of time
Calculations
• Make a step by step guide for your
calculations that you will perform tomorrow
to get
– Primary productivity of mung beans over 7 days
– Secondary productivity of pill bugs over 1 day
While we wait…..
• Lab Posters on productivity!
• Today: Introduction, method, data table
(blank), calculations (once approved by Ms.
Poole)
• Make it neat and presentable!