%0 Research article
%T Detection of electric resistivity tomography and evaluation of the sapwood-heartwood demarcation in three Asia Gymnosperm species
%A Lin, Chen-Jung
%A Chung, Chih-Hsin
%A Yang, Te-Hsin
%A Lin, Far-Ching
%D 2012
%J Silva Fennica
%V 46
%N 3
%R doi:10.14214/sf.440
%U https://silvafennica.fi/article/440
%X The proportions of sapwood and heartwood of trees have significant  impacts on various uses. Electric resistivity tomography (ERT) and  corresponding electrical resistance (ER) value maps were examined in  Japanese cedar (Cryptomeria japonica D. Don), Taiwania (Taiwania  cryptomerioides Hayata), and Luanta fir (Cunninghamia konishii Hayata)  trees. The position of the sapwood-heartwood demarcation was measured on  incremental cores from living trees and the corresponding ER of the  sapwood-heartwood boundary was acquired from the ER map. A positive  significant relationship was found between the maximum ER plus minimum  ER values (ERmax + ERmin) and ER of the sapwood-heartwood demarcation  from the tomographic data. The position of the sapwood-heartwood  demarcation was determined by corresponding ER, and the critical ER can  be established by the ERmax + ERmin value of the tomographic data. The  results from this study indicate that ERT technique can be used to  determine the position of the sapwood-heartwood boundary and can serve  as a methodology in undamaged living trees of Gymnosperm species.