Environmental
|
LAI-2000 Software and Data
Data files are stored in the LAI-2000 memory located in the control unit. A data file is stored after the last reading is made. Though data files can be viewed on the display of the control unit, additional data analysis may be necessary. The LAI-2000 now comes with new FV2000 Windows Software for downloading, viewing and recomputing LAI-2000 data files.
An LAI-2000 Data File looks like the example below.
The file has three parts: Header, Statistics, and Observations.
The Header includes the file number (assigned by the system), the date,
and a time stamp indicating when the file was created. The user is prompted
for two remarks when a file is created (Crop Alfalfa and Plot 15.5 in the
example above). The remaining part of the header contains the results of
the LAI calculations: Leaf Area Index (LAI), standard error of the LAI determinations
(SEL), fraction of the sky visible beneath the canopy (DIFN), Mean Tip Angle
(MTA), standard error of the MTA (SEM) and the number of pairs of above and
below observations used to calculate these results (SMP).
The Statistics group contains five rows of five numbers: ANGLES are the
mid-angles of each of the five rings’ field of view. CNTCT# are the
mean contact frequencies (the log of the transmittances divided by the path
length) of all the computed transmittances, STDDEV are the standard errors
of the contact frequencies, DIST are the path lengths, and GAPS are the fraction
of the sky visible for each detector ring.
The Observations each have a label (A or B), a sequential number, a time
stamp, and five values. The five values are the signals from the five rings
of the detector, and the A or B indicates above or below canopy readings.
