tree-ring英t'riːr'ɪŋ美t'riːr'ɪŋCOCA⁸⁷²²⁰BNC¹¹⁴⁰²⁴⁺⁵ 基本例句 树木年轮¹⁰⁰ Important findings Tree-ring chronological eigenvalues indicated the upper three sites had similar variation, but differed from the low- elevation chronology. 年表间相关和主成分分析结果都显示出海拔梯度上的变化规律,但下限差异显著; doi