概括
树环中的氧同位素比率作为大气降水和平均年温度的可靠指标. 本研究量化了这些比率,证明了它们在气候和海拔研究中的实用性.
科学领域:
- 古气候学 古气候学
- 同位素地球化学 同位素地球化学
- 登德罗年代学 登德罗年代学
背景情况:
- 树环纤维素中的氧同位素比例 (delta(18) O) 与大气降水和温度相关.
- delta 的变化受到地理位置和海拔高度的影响.
研究的目的:
- 分析树环纤维素三角体和环境因素之间的关系.
- 为了确定度和温度之间的定量关系.
- 为了评估海拔对降水和树木环中的delta(18) O的高度影响.
主要方法:
- 在树环纤维素中分析氧同位素比率 (delta(18) O).
- 纤维素三角形{18) O与降水和温度数据的比较.
- 使用同位素数据计算温度间隔率.
主要成果:
- 在沿海站附近,对纤维素中的delta{18) O确定了0.41每毫升每摄氏度的灵敏度.
- 华盛顿州雷尼尔山 (Mount Rainier, Washington) 观测和量化了三角洲的高度变化.
- 从树环数据计算出每1000米的温度间隔率为5.2 ± 0.5°C,与区域值一致.
- 在纤维素delta{18}O和与叶子水平衡的二氧化碳之间发现了每毫升16的一致偏移.
结论:
- 树环纤维素三角体 ((18) O是重建过去的温度和降水模式的有价值的代理.
- 对树环的同位素分析提供了可靠的温度间隔率估计.
- 这项研究验证了氧气同位素在树木环中的使用,用于古气候研究.
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