论文部分内容阅读
对采自北京大学校园内的白皮松(Pinusbungeana)树轮α-纤维素的δ13C进行了分析,结合北京气象台的气象记录,建立树轮δ13C与气候各要素的回归方程,重建值与观测值吻合较好,表明北京地区树轮α-纤维素的碳稳定同位素与1928—1999年3—9月的平均气温及6—9月的平均降雨量显著相关,重δ13C对应于3—9月的低温和6—9月的少雨,轻δ13C对应于3—9月的高温和6—9月的多雨,而3—9月的温度正好是适宜树木生长的光合作用所需要的最佳温度,6—9月正好是一年中降雨最充沛的时期。由此认为:树轮δ13C值与生长季节的降水和气温密切相关,可以考虑作为季风盛行地区的气候替代性指标,在一定程度上反映了季风盛行区白皮松树轮纤维素碳稳定同位素与气候因子的关系。
The δ13C of Pinus bungeana tree-ring α-cellulose collected from Peking University campus was analyzed. Based on the meteorological records of Beijing Meteorological Observatory, the regression equation of tree-ring δ13C and climate elements was established. The reconstructed values were in good agreement with the observed values It shows that the carbon stable isotopes of tree-ring α-cellulose in Beijing are significantly correlated with the mean temperature in March-September from 1928 to 1999 and the average rainfall in June-September. The heavy δ13C corresponds to the low temperature in March-September June-September light rain, light δ13C corresponds to the high temperature in March-September and June-September rainy, while the temperature in March-September is just the optimum temperature for photosynthesis suitable for tree growth, 6-9 The month is exactly the year with the heaviest rainfall. Therefore, the δ13C value of tree ring is closely related to the precipitation and temperature in the growing season, which can be considered as a proxy for climate substitution in the monsoon prevailing area, which reflects to some extent the stable carbon isotope of cellulose and the climatic factors Relationship.