Delta SS1-UM-1.05 Benutzerhandbuch

••••

In normal use the SunData software calculates Leaf Area Index (

) based on

readings from the SunScan probe and from the Beam Fraction Sensor (if fitted).
These calculations also require information about the distribution of leaf angles and
absorption of light by leaves within the canopy and knowledge of the solar angle
calculated from the time of day and local latitude and longitude.

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Before it can make sensible calculations of the Leaf Area Index, SunData needs to
know what values to use for the above settings.

♦

 Press 

, use the 

←

←

←

←

→

→

→

→

 arrow keys to

select the 

 menu, and the 

↑↑↑↑↓↓↓↓

keys to highlight 

, and press 

.

Type in a 

 for your present site, and

set the 

 and 

 by

pressing  

 and typing in the

appropriate values. When everything is
correct, to accept it

♦

 Press 

 again, then select 

 and press 

. Now set the local

time and date in the dialog box.  You also need to set the appropriate offset from
GMT for your time zone.  Set 

 to between -12.0 and +13.0

hours.  Remember to make allowance for any special seasonal offsets, such as
“Summer Time”, “Daylight Saving”. For example: British Summer Time is
GMT+1, India is GMT+5.5, and USA EST is GMT - 5.0.

♦

 Press 

 to accept the settings and return to the Title screen.

♦

 Use the 

←

←

←

←

→

→

→

→

 arrow keys to set the 

 to

.  Set the 

 (

llipsoidal 

eaf 

ngle

istribution 

arameter) to 1.  Press 

 to accept

these settings.

Later sections in Measurement Options and LAI Theory give explanations and
advice on choosing values for these parameters.

♦

 Set the 

 format to 

.  Leave the 

 and 

 names unchanged.

The options for 

 (

, 

 and 

) have an important effect on the display

of readings but they also interact with the setting for 

 (

 or 

) to

determine the sequence of readings required.