Determination of optimal photographic conditions for anatomical characterization of ten timber species of Costa Rica

Abstract

There is an absence of studies on tropical timber species that show the optimization in quantity and dimensions of wood photography in anatomical studies, an aspect that restricts the statistical representativeness in anatomical studies in tropical species. The study presented as an objective to determine the dimensions and minimum quantity of macroscopic photographs that can be represented in tropical species and to analyze the relationship between photographic dimensions and anatomical characteristics. Ten tree species were selected for this purpose; eight to fifteen cylindrical wood specimen of 12.5 mm diameter and 75 mm length were collected from each species, which were dried and photographed on the transverse side. The results showed a variation from 19 to 35 photographs as minimum quantity per species, being Spondias mombin the species with the highest requirement of photographs with 35, while Caryocar costarricense the one with the lowest amount of minimum photographs; furthermore, the optimal common dimension of photographs was 1.25 x 1.25 mm, being Peltogyne purpurea the species that could be worked with even lower dimensions. The combination of the minimum number of photographs and the optimal dimension allowed to be representative and reproducible in more than 90 %. Finally, a correlation was found between the size of the image and the diameter of the vessels; the ratio was that as the diameter of the vessels is smaller, it is possible to work with smaller photographs with a ratio greater than 70 %.