Effects of Tree Age on Climate Signal--Evidence from Young and Old Trees in a Temperature Forest

摘要

This analysis aims to evaluate the hypothesis that the effect of age on the climate signals should be considered, even if the inherent biological trend has been removed using dendroecological techniques. 72 young and old Pinus koraiensis trees from broadleaved and coniferous mixed forests were disaggregated into two age classes, the young trees (average age 63 years) and the old trees (average age 184 years) and analyzed to evaluate this hypothesis. Our results that tree-ring width tendencies and climate signals are age-related support the hypothesis that sensitivity to particular climatic conditions varies with age. Firstly, young trees always grow faster than old ones at the same climate condition. Secondly, young trees are more sensitive to mean temperature. While the growth of old trees correlates with monthly precipitation. In addition, common dendrochronological techniques can remove the natural biological growth trend, but lose more climate information with low frequency, especially for young trees.