THE NITROGEN CYCLE GAME
The game begins as organic nitrogen and as players move through the game nitrogen is
transformed to ammonium salts (NH ) and nitrate (NO ) in the journey toward crop
uptake. Ladders help the players advance on their way to the green zone while chutes
represent the loss of nitrogen through leaching, runoff, immobilization, erosion or
denitrification. If a player is volatilized or denitrified, he/she ends up in the air and loses
two turns before the player starts all over. If a player encounters erosion or runoff, he/she
ends up in surface water. If a player encounters leaching, he/she ends up in ground water.
Three to six players select from tokens representing three different types of organic
nitrogen: legume nitrogen, crop residue nitrogen, and manure nitrogen. Each player spins
or throws the die to determine who goes first. The player with the highest number goes
first and play proceeds in a clockwise direction. Each player throws the die and moves
the corresponding number of squares across the game board (no diagonal moves are
permitted). Two or more players are permitted to land on a square simultaneously. If a
player lands at the BASE of a ladder, the player moves up to the top of the ladder. If a
players lands at the TOP of a chute, the player slides down the chute to the bottom. The
player must roll the exact number on the dice to win. The first player to arrive at Crop
Uptake (Square 25) is the winner. Use the ecologist sheet to record you progress of the
game.
Mineralization: Decomposers change organic nitrogen stored in dead organisms to
inorganic nitrogen. They changed ammonia (NH4 ) to ammonium salts (NH ).
Immobilization: Microbes (bacteria) take in nitrogen from the soil and make it
unavailable to plants.
Nitrification: Nitrogen fixing bacteria change nitrogen to a form that can be used by
plants. They change ammonium salts (NH ) to nitrite (NO ) and other type of fixing
bacteria changes nitrite to nitrate (NO ).
Leaching: Nitrogen moves through the soil into groundwater. This contaminates streams
and drinking water.
Volatilization: Nitrogen escapes into the air after denitrification.
Runoff: The soil is saturated with water because it does not have protective vegetation
and has a steep slope so organic and inorganic nitrogen together with other materials is
carried by excess water into streams and other water sources.
Denitrification: Bacteria in poorly drained soils change nitrate to nitrogen or nitrous
oxide gas and put it into the atmosphere. Also nitrate that reaches the oceans is returned
to the atmosphere.
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Went Up
Went Down
Continue journey to Crop Uptake
Loss of Nitrogen
Ecologist Notes
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Mineralization
Volatilization
Denitrification
Runoff
Nitrification
Immobilization
Leaching
Reason
N2
NO2
NH3
AIR
23
21
Crop
Uptake
22
24
25
17
20
19
NH4
16
18
Immobilizatio
n
Leaching
11
13
14
15
7
6
9
2
1
8
3
4
START
NO3
GROUNDWATER
5
S
U
R
F
A
C
E
W
A
T
E
R