Oxygen isotopes as a valuable tool for measuring annual growth in tropical trees that lack distinct annual rings
Oxygen isotopes as a valuable tool for measuring annual growth in tropical trees that lack distinct annual rings
复制标题
DOI：
10.2343/geochemj.2.0312
复制
发表时间：
2014-07
影响因子：
0.8
通讯作者：
Chenxi Xu;M. Sano;K. Yoshimura;T. Nakatsuka
中科院分区：
文献类型：
--
作者：
Chenxi Xu;M. Sano;K. Yoshimura;T. Nakatsuka
一些来自热带地区的树木缺乏视觉上可检测和一致的年轮。因此，我们已经测量了径向变化的纤维素氧同位素的树木生长在季节性干燥的森林北方老挝探索的可能性，如果这种方法可以用于识别的年轮。7年生东京野茉莉（Styrax tonkinensis（S. tonkinensis）和2株半心榕（Ficus semicordata var. semicordata（F.在森林中，我们检查了。高分辨率的S. tonkinensis和F.半波资料显示出清晰的周期，振幅分别为5‰和9‰。为了进一步检验我们观测到的氧同位素循环是否为周年循环，我们采用了树轮纤维素氧同位素模型。模型的输入数据为相对湿度和模拟的降水δ 18O。模拟结果独立支持我们的探测氧同位素年周期。因此，我们得出结论，树轮纤维素氧同位素有很大的潜力，以确定在热带树木，通常缺乏独特的年轮在季节性气候的背景下，年轮。
Some trees from tropical areas lack visually detectable and consistent annual growth rings. As such, we have measured the radial variation of cellulose oxygen isotopes in trees that grow in seasonally dry forests of Northern Laos to explore the possibility if this method can be used for the identification of annual rings. One disk from a 7-year-old Styrax tonkinensis (S. tonkinensis) in plantation and two cores from two Ficus semicordata var. semicordata (F. semicordata) in forests were examined. High-resolution cellulose oxygen isotopes of S. tonkinensis and F. semicordata show clear cycles with amplitudes of 5‰ and 9‰, respectively. To further test if the oxygen isotope cycles that we observed are annual or not, a tree ring cellulose oxygen isotope model is employed. Input data of the model are relative humidity and modeled precipitation δ 18 O. The modeling results independently support our detection of oxygen isotope annual cycles. Therefore, we conclude that tree ring cellulose oxygen isotopes have great potential to identify annual rings in tropical trees, which typically lack distinct annual rings in the context of seasonal climate.