GLBRC Sustainability Data Catalog

Leaf Area Index (LAI) — GLBRC Biofuel Cropping System Experiment

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Leaf Area Index (LAI) measurements for all BCSE treatments (G1-G10) at KBS. From 2009 to 2013, LAI was measured with a Licor LAI-2000 meter and from 2013 to 2017 with an AccuPar LP-80 Ceptometer. Dual measurements using both meters were conducted in 2013 in order to compare results.

This datatable is part of the Leaf Area Index on the GLBRC Biofuel Cropping System Experiment dataset.

The leaf area index was measured to estimate the phenology and growth patterns of the different biofuel crops.


Experiment: GLBRC Biofuel Cropping System Experiment
Data available from: June 2009 to October 2017
Dataset: GLBRC148
Datatable ID: GLBRC082-007.4
Repository link:
Last Updated 2023-10-24
Variate Description Units
sample datetime date and time of measurement, the plus sign indicates the time relative to Universal Coordinated Time (UCT).
local datetime the time in the eastern time zone either standard time or daylight saving time depending on the date.
treatment experimental treatment
replicate replicate nested within treatment
direction direction and plant number
lai leaf area index m^2/m^2
sel standard error of lai m^2/m^2
difn fraction of sky visible
mta mean tilt angle
sem standard error of MTA
smp number of sample pairs used
comments notes about the data row
instrument the instrument used to measure LAI
mean above par mean PAR above the canopy in micromoles/(m^2 s)
mean below par mean PAR below the canopy in micromoles/(m^2 s)
tau ratio between the above and below canopy PAR
chi (leaf distribution parameter): ratio of the projected area of an average canopy element (a leaf, for example) on a horizontal plane to its projection on a vertical plane; the default value for χ is 1.0, which assumes the canopy angle distribution to be spherical.
fb (fractional beam radiation): ratio of direct beam radiation coming from the sun to radiation gathered from all ambient sources, like the atmosphere, or reflected from other surfaces
zenith angle angle between the point in the sky directly overhead vertical, called the zenith (0°), and the position of the sun. The angle is calculated based on the global position, time of day, and location

Data Excerpt

sample_datetime local_datetime treatment replicate direction lai sel difn mta sem smp comments instrument mean_above_par mean_below_par tau chi fb zenith_angle
2017-10-27 12:52:00 +0000 2017-10-27 08:52:00 UTC G8 R1 EP3 0.39 LAI AccuPAR LP-80 Ceptometer 11.2 8.1 0.719 1.0 0.02 83.0
2017-10-27 12:51:00 +0000 2017-10-27 08:51:00 UTC G8 R1 EP1 0.67 LAI AccuPAR LP-80 Ceptometer 10.9 6.1 0.56 1.0 0.02 83.0
2017-10-27 12:51:00 +0000 2017-10-27 08:51:00 UTC G8 R1 EP2 0.72 LAI AccuPAR LP-80 Ceptometer 11.0 6.0 0.542 1.0 0.02 83.0
2017-10-27 12:50:00 +0000 2017-10-27 08:50:00 UTC G8 R1 WP3 0.79 LAI AccuPAR LP-80 Ceptometer 11.3 5.7 0.505 1.0 0.02 83.0
2017-10-27 12:48:00 +0000 2017-10-27 08:48:00 UTC G8 R1 WP2 0.79 LAI AccuPAR LP-80 Ceptometer 12.1 6.2 0.51 1.0 0.02 84.0
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