New Methods to Quantify Canopy Structure of Leafless Boreal Birch Forest from Hemispherical Photographs
نویسندگان
چکیده
منابع مشابه
Automatic thresholding for hemispherical canopy-photographs based on edge detection
The analysis of hemispherical photographs is nowadays an established method for assessing light indirectly and describing canopy structures. In this article, we present an automatic threshold algorithm for separating canopy and sky by edge detection. The algorithm was evaluated under different canopy conditions by comparing its results for canopy openness, fractal dimension and diffuse transmit...
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Objectives Hemispherical photography is used to characterize the structure of canopies and measure the gap fraction directional variation to retrieve variables such as the leaf area index (LAI), the fAPAR {Jonckheere, 2004 #3541};{Weiss, 2004 #2872}. Optical systems are not perfect and at least two main characteristics are required: • The coordinates of the optical centre • The projection funct...
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ژورنال
عنوان ژورنال: Open Journal of Forestry
سال: 2013
ISSN: 2163-0429,2163-0437
DOI: 10.4236/ojf.2013.32012