Making Measurements
Light Response Curves
4-28
Using the LI-6400
4
3
Set the temperature
Set the temperature control for constant leaf temperature.
4
Set the chamber humidity
After the chamber has been clamped onto the leaf for a few minutes, note the
H2OS_mml
value, then change the flow control to constant mole fraction con-
trol, and target that value.
5
Set the chamber CO
2
Control constant sample CO
2
, targeting the desired value.
6
Open a log file
Make sure youÕve got the computations, prompts, log list, etc. that you need.
7
Area and Stomatal Ratio
Are they correct?
8
Establish the Real Time Graphics display
Pick the display
Ò
A-Q, RH_Flow, totalCV
Ó
(press
4
then
f1
). You might wish
to adjust the scale of the Photo-PAR plot.
9
Match the IRGAs
Be sure
CO2S_µml
is stable before you do this.
10
Launch the ÒLightCurveÓ Autoprogram
Press 5 then
f1
. Pick ÒLight CurveÓ from the list.
When asked Ò
Append to current data file?
Ó Press
Y
When asked Ò
Enter the desired light values?
Ó, edit the list as needed,
and press
enter
.
When asked Ò
Enter min time
Ó, enter the desired value. 120 seconds is usu-
ally adequate. This is the time after each light level change that the system
will wait before checking stability to see if it can log.
When asked Ò
Enter max time
Ó, enter the desired time, in seconds. After the
minimum time, it will check stability up to this time to see if it can log. Enter
200. That gives it 80 seconds after the initial 120 second delay for photosyn-
thesis to stabilize.
For the stability, enter 1%
Open 3.01 and below: When asked Ò
Match before each obs?
Ó) press
N
.
Summary of Contents for LI-6400
Page 1: ...Using the LI 6400 Portable Photosynthesis System ...
Page 15: ...Part I The Basics ...
Page 16: ......
Page 174: ...Making Measurements Answers to Questions 4 56 Using the LI 6400 4 ...
Page 175: ...Part II Useful Details ...
Page 176: ......
Page 200: ...Standard Tools Power ON Hooks 5 24 Using the LI 6400 5 ...
Page 214: ...Real Time Data Real Time Graphics 6 14 Using the LI 6400 6 ...
Page 234: ...Environmental Control Light Control 7 20 Using the LI 6400 7 ...
Page 244: ...Light Sensor Considerations Gallium Arsenide Phosphide GaAsP Sensor 8 10 Using the LI 6400 8 ...
Page 288: ...Data Logging Making Your Own AutoPrograms 9 44 Using the LI 6400 9 ...
Page 289: ...Part III Working With Files ...
Page 290: ......
Page 312: ...The LPL File System Troubleshooting 10 22 Using the LI 6400 10 ...
Page 340: ...Downloading Files Using a Data Capture Program 11 28 Using the LI 6400 11 ...
Page 375: ...Part IV Configuration Issues ...
Page 376: ......
Page 420: ...Defining User Variables Old Style vs New Style 15 18 Using the LI 6400 15 ...
Page 454: ...Using an Energy Balance Further Reading 17 12 Using the LI 6400 17 ...
Page 455: ...Part V Maintenance Troubleshooting ...
Page 456: ......
Page 572: ...Troubleshooting Useful Information 20 46 Using the LI 6400 20 ...
Page 593: ...Part VI Programming ...
Page 594: ......
Page 622: ...Programming with LPL Compiler Directives 22 28 Using the LI 6400 22 ...
Page 846: ...Index I 16 Using the LI 6400 ...