珠江三角洲马尾松年轮中S的环境指示意义

为探讨珠江三角洲马尾松年轮S含量作为生物指标追踪区域大气污染历史变迁的意义，该文通过树木年轮化学分析方法，研究了肇庆鼎湖山和南海西樵山马尾松木质部S含量的时间变化规律。结果表明，两地马尾松木质部S平均含量随时间的增长呈明显上升趋势，在最晚形成的木质部中S含量最高；在20世纪80年代以前，两地相同时期的马尾松木质部S含量差异不显著，80年代后，西樵山马尾松木质部S含量显著高于同期鼎湖山马尾松木质部S含量；从两地马尾松木质部S最终年表发现，木质部S含量存在着1970年前、1971—1985年和1986—2002年3个明显区别的时段；基于两地马尾松木质部中S含量时间变化规律，结合珠江三角洲20世纪80年代以后的某些特定经济指标分析，恢复了研究地大气污染历史:1941—1970年为大气相对清洁期；1971—1985年为大气污染开始出现并持续增强期；1986—2002年为大气污染最严重期。 

Environmental bioindication of sulphur in tree rings of Masson pine(Pinus massoniana)in the Pearl River Delta of China

In order to identify the potential of sulphur(S) content in the rings of Masson pine(Pinus massoniana) in the Pearl River Delta as a bio-indicator to regional history of atmospheric pollution,dendrochemistry was used to determine the temporal distribution of S content in the xylem of Masson pine from Zhaoqing Dinghushan Mountain and Nanhai Xiqiaoshan Mountain,Guangdong Province,southern China.The results indicated that the content of xylem S increased temporally and peaked in the rings formed in the latest years at the both sites.In the rings formed at the same periods before the 1980s,S content was not significantly different between the two sites,while in the rings formed at the same periods after the 1980s,S content at Xiqiaoshan Mountain was significantly higher than that at Dinghushan Mountain.The chrono-sequences of S index at the both sites could be easily marked as three periods: before 1970,1971-1985 and 19862002.Based on the temporal changes of the xylem S content and certain social-economic index after the 1980s in the delta,the history of atmospheric pollution at the studied sites could be reconstructed as the followings: 1) before 1970,a period in which the air was relatively clear;2) 19711985,a period in which the air was gradually polluted;3) 1986-2002,a period in which the air was most severely polluted in the delta.