|SILVICULTURE AND STAND DYNAMICS|
|| ualberta.ca | Faculty of Agricultural, Environmental and Life Sciences | Renewable Resources|
Phil Comeau (University of Alberta, Dept. of Renewable Resources),
The model calculates the location of the sun, partitions open sky total PPFD into diffuse and direct components, and estimates the penetration of each through the canopy to the selected point of interest. Direct PPFD is assumed to come from the location of the sun; diffuse PPFD is assumed to be evenly distributed across 480 equal-area segments of the sky.
LITE provides maps of LAI and PPFD across the study site and provides information on the light regime at selected locations. Routines for entering, merging, and editing data are also provided. The model is written for use with MS-WindowTM
SLIM (Spot Light Interception Model) is a program designed to estimate LAI, gap fraction, and fractional transmittance from hemispherical photographs or LICOR LAI-2000 Plant Canopy Analyzer data. In addition, SLIM prepares LAI-2000 data or hemispherical photos for use by the LITE model. SLIM includes the automatic thresholding and batch processing capabilities.
LITE and SLIM are designed to work with Windows XP, Windows 7 and compatible operating systems.
As with any software, the user must accept all responsibility for interpretation and application of the results that are provided by these programs.
A brief overview of these models is provided in: Modeling light using SLIM & LITE.htm
Please report problems and send comments or questions to: Phil.Comeau@ales.ualberta.CA
Installation of light modeling software
To install SLIM and LITE, download and run the file "Light Modeling.msi". Appropriate drivers and software will be installed. Information on how to use these programs, and on the underlying algorithms used, is provided in the help files.
(If you are running Windows 7 you need to have the help file reader installed. If help files do not open after selecting Help in LITE or SLIM - then you will need to install winhlp32. To get winhlp32 go to Microsoft support at: http://support.microsoft.com/kb/917607).
To download the tutorial on batch processing in SLIM click here and save this file:SLIM - Instructions for Batch Processing.pdf
Addtitional notes on processing hemispherical photographs are availabe in: updated slim notes april 2010
Sample data files are included in the zip file labeled â€œSample data files for SLIM & LITE.zip. You should save this file on your hard-disk, then you will need to use WINZIP to unzip the contents of this file to an appropriate folder on your hard-disk. To download the sample data files (and description) click here and save this file: Sample data files for SLIM & LITE.zip
Acknowledgements: Support for development of these light modeling tools has been provided by a number of sources. These include: B.C. Ministry of Forests and Range, University of Alberta, Forest Renewal B.C., B.C. Forest Science Program, and the Natural Sciences and Engineering Research Council of Canada.