Forest Investment Account (FIA) - Forest Science Program
FIA Project Y073092

    Light and Tree Growth in Complex Forest Stands
Project lead: Simpson, David
Author: Simpson, David G.
Imprint: Vernon, BC : BC Ministry of Forests, 2007
Subject: Forest Investment Account (FIA), Growth (Plants), British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Within the FSP Timber Growth and Value Program this proposal addresses Theme 1.0 (Basic research on tree growth and stand development), Topic 1.1 (Complex stands), and is directly related to the research area of 'light level effects related to tree and stand growth in multi-storied standsí. The objective of the project is to aid the development of the MoF Tree and Stand Simulator for complex forest types (TASS-III) by: (1) providing relationships between tree height increment and light levels, and, (2) evaluating model estimates of light and tree growth in real forests. Relationships between tree growth and light are being developed by destructive sampling and measurement of young saplings growing at varying distances from stand edges. Growth measurements include total height, leader growth over the past 5-years, annual branch extension for 3- and 5-year-old branches, and stem diameter measurements at ground level and for the 3rd and 5th internodes. Stem sections have been taken and are stored frozen for more detailed measurements. Growing season light as % above canopy light (PACL) for each tree will be determined by analysis of digital hemispherical photographs taken at the location of each tree. Evaluation of the TASS light model estimates will be done using real light data collected in an interior Douglas-fir partially cut stand near Westwold. A portion of this stand has been stem mapped and within this area an array of 18 fixed light sensors has been installed. Data from these sensors will be used along with data from a sensor in a nearby clear-cut to determine PACL for specific points in the stand. More spatially detailed light data has been collected by a TRAM system, along a 30m transect in the stem-mapped area. Model estimates of PACL will be compared with measured light values to evaluate the TASS light model.
Related projects:  FSP_Y051092FSP_Y062092


Final Technical Report (1.7Mb)

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Updated August 16, 2010 

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