雅鲁藏布大峡谷羚牛牙齿珐琅质碳、氧同位素组成及其环境意义  

δ^(13)C,δ^(18)O Values and Their Paleoenvironmental Significance of Modern Asian Takin Tooth Enamel from the Yarlung Zangbo Grand Canyon

作　　者：李玉梅[1,2] 刘东生[2] 洪冰[3] 储国强[2] 洪业汤[3] 朱咏煊[3] 彭建华[3] 董丽敏[3] 韩家懋[2] 

机构地区：[1]中国科学院研究生院计算地球动力学实验室,北京100049 [2]中国科学院地质与地球物理研究所,北京100029 [3]中国科学院地球化学研究所,贵州贵阳550002

出　　处：《地理科学》2009年第6期917-922,共6页Scientia Geographica Sinica

基　　金：国家自然科学基金(4077211240302034);中国科学院研究生院院长基金(O65001D);中国科学院环境地球化学国家重点实验室开放基金

摘　　要：以雅鲁藏布大峡谷的羚牛为主要研究对象,讨论其牙齿珐琅质羟基磷灰石结构碳酸盐的碳、氧同位素组成与生活环境之间的关系。羚牛牙齿的碳同位素组成分布范围相当宽,且随着栖息地海拔高度的增加而变重,反映了食谱中C4植物从无到有、由少到多的变化趋势。C4植物含量最高可能达到70%。这一变化与当地自然带的划分相吻合。羚牛牙齿珐琅质结构碳酸盐的δ18O值分布范围较窄,与海拔高度之间没有明显的相关性。氧同位素分馏可能与水源和物种均有关。This paper addresses the δ^13C,δ^180 values and paleoenvironmental significance of modern Asian takins （Budorcas taxicolor）, yaks and cattle-yaks tooth enamel from the Yarlung Zangbo Grand Canyon, and tooth enamel of modern reindeers （Rangifer tarandus） from Svalbard, the Arctic. The Yarlung Zangbo Grand Canyon has a length of about 496.3 km and cuts its way through the eastern Himalayas. Its climate ranges from subtropical to arctic. The takin （Budorcas taxicolor） is a large ungulate belongjing to the Bovidae. There are four subspecies： B. taxicolor taxicolor, B. taxicolor bedfordi, B. taxicolor tibetana and B. taxicolor whitei. B. taxicolor taxicolor is found in the eastern Himalayas, such as the Yarlung Zangbo Grand Canyon. Stable carbon and oxygen isotopic composition of tooth enamel has been established as a valuable tool for reconstructing paleo- environment. In this paper, tooth enamel samples were obtained from modern Asian takins, yaks, cattle-yaks and reindeers for C and O isotope analysis.δ^13C values of takin tooth enamel range from -19.3‰ to -2.2‰. The takins Jiving at an altitude of 1300 m have δ^13C values ranging from -19.3‰ to -18.9‰, with an average δ^13C value of -19.1‰; δ^13C value of takins living at an altitude of 1700 m is -10.7‰; δ^13Cvalues of takins living at an altitude of 1830 m are from -10.7‰ to -10.3‰, with an average δ^13C value of -10.5‰; takins living at an altitude of 3000 m have δ^13C values of -4.6‰ to -2.2‰, with an average δ^13C value of -3.4‰. There is a direct correlation betweenδ^13C values of takin tooth enamel and the altitude, a higher altitude equaling a higher δ^13CC value. This could be due to an association with C4 plants. Higher δ^13C values such as -3.4‰ could suggest consumption of large amounts of C4 plants by the animals. It is more likely attributed to the abundance of C4 plants in this area. The lower enamel δ^13C values such as - 19.1‰ indicate that the takins were feeding predominantly on C3 plants, c

关 键 词：雅鲁藏布 羚牛 碳同位素 氧同位素 C4植物 

分 类 号：X142[环境科学与工程—环境科学]