Impact of decline on the concentration of chemical elements in the wood of declined and healthy Iranian oak (Quercus brantii Lindl.)

Dendrochemistry is the science of analyzing the elements of tree rings that identify the biochemical changes of a tree under environmental changes. In order to investigate the change in the concentration of some of the chemical elements in the wood of declined trees compared to healthy ones, three healthy and declined Iranian oak trees (Quercus brantii Lindl.) in forests close to Khorramabad were cut and a disk was prepared from each tree. Then the vegetative rings of the last 35 years were cut into three five-years and two 10-years-old cuttings and extracted by the wet digestion method and the concentration chemical elements were measured using the atomic absorption apparatus. The results showed that potassium concentration in the wood of declined trees was higher than healthy ones while calcium and copper concentrations in the wood of healthy trees were less. Also, the ratio of sodium and calcium to potassium concentration in the trees of the two communities was significantly different. Correlation between elemental concentration and radial growth of healthy trees was not significant, whereas in declined trees there was a negative and significant correlation between calcium and lead content and radial growth. According to the results, the effect of climatic factors seems to be the most effective among several factors.