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The estimation of canopy attributes from digital cover photography by two different image analysis methods

Francesco Chianucci   , Ugo Chiavetta, Andrea Cutini

iForest - Biogeosciences and Forestry, Volume 7, Issue 4, Pages 255-259 (2014)
doi: https://doi.org/10.3832/ifor0939-007
Published: Mar 26, 2014 - Copyright © 2014 SISEF

Research Articles


Proximal sensing methods using digital photography have gained wide acceptance for describing and quantifying canopy properties. Digital hemispherical photography (DHP) is the most widely used photographic technique for canopy description. However, the main drawbacks of DHP have been the tedious and time-consuming image processing required and the sensitivity of the results to the image analysis methods. Recently, an alternative approach using vertical photography has been proposed, namely, digital cover photography (DCP). The method captures detailed vertical canopy gaps and performs canopy analysis by dividing gap fractions into large between-crown gaps and small within- crown gaps. Although DCP is a rapid, simple and readily available method, the processing steps involved in gap fraction analysis have a large subjective component by default. In this contribution, we propose an alternative simple, more objective and easily implemented procedure to perform gap fraction analysis of DCP images. We compared the performance of the two image analysis methods in dense deciduous forests. Leaf area index (LAI) estimates from the two image analysis methods were compared with reference LAI measurements obtained through the use of litter traps to measure leaf fall. Both methods provided accurate estimates of the total gap fraction and, thus, accurate estimates of the LAI. The new proposed procedure is recommended for dense canopies because the subjective classification of large gaps is most error-prone in stands with dense canopy cover.

  Keywords


Digital Cover Photography, Canopy Cover, Gap Fraction, Leaf Area Index, Dense Canopy

Authors’ address

(1)
Francesco Chianucci
Ugo Chiavetta
Andrea Cutini
Consiglio per la Ricerca e la sperimentazione in Agricoltura - Forestry Research Centre, v.le Santa Margherita 80, I-52100 Arezzo (Italy)

Corresponding author

 
Francesco Chianucci
francesco.chianucci@entecra.it

Citation

Chianucci F, Chiavetta U, Cutini A (2014). The estimation of canopy attributes from digital cover photography by two different image analysis methods. iForest 7: 255-259. - doi: 10.3832/ifor0939-007

Academic Editor

Francesco Ripullone

Paper history

Received: Dec 20, 2012
Accepted: Mar 03, 2014

First online: Mar 26, 2014
Publication Date: Aug 01, 2014
Publication Time: 0.77 months

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