Fluctuation Factors of Bioelectric Potential and its Application to Decline Estimation for Zelkova

Abstract

There is a high possibility for declining trees to have fallen and some accidents have been occurring. Thereby, an accurate diagnosis is strongly necessary to maintain and manage the physiological status of trees. In addition, it is desired that a simple and non-destructive evaluation would be possible for diagnosis. Therefore, the bioelectric potential of trees has been measured for a long period of time these days. The analysis of measured potential shows that there are several factors which influence the potential fluctuation. In this paper, the bioelectric potential is found to be affected by temperature and precipitation, and there is a difference in the patterns of potential fluctuation between healthy and declining individuals. In particular, it is shown that there is a difference between the differential curves of the bioelectric potential and the periodic features. By using the obtained results, new indices for estimating the degree of tree decline based on the bioelectric potential are obtained. This paper describes the analyses of bioelectric potential fluctuation factors and suggests some indicators for estimating the degree of decline.