树轮记录的青藏高原南部过去526年降水变化特征  

Precipitation variations during the last 526 years inferred from tree-ring widths on the Southern Tibetan Plateau

作　　者：刘晶晶[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室,兰州730000

出　　处：《兰州大学学报（自然科学版）》2014年第3期293-298,共6页Journal of Lanzhou University(Natural Sciences)

基　　金：中国科学院寒区旱区环境与工程研究所青年基金项目(51Y251A51);国家重大科学研究计划项目(2010CB950104);中国科学院交叉团队资助项目(29Y329B91)

摘　　要：利用位于南木林的大果圆柏树轮宽度资料,分析了树轮宽度对气候要素的响应关系,研究结果发现制约树木径向生长的主要因子是年总降水.基于一元线性回归模型建立的转换方程(方差解释量为45.94%),重建了南木林1485-2010年的年总降水(上一年7月至当年6月).重建结果表明:南木林降水存在明显的年代际的气候变化韵律,相对于平均值偏湿的持续时段发生在公元1490-1510,1530-1550,1620-1640,1680-1720,1740-1750,1840-1850,1880-1910,1960-1990年,相对于平均值偏干的持续时段发生在公元1520,1560-1610,1650-1670,1730,1760-1830,1860-1970,1920-1950,1990年以后.与林周地区及高原南部区域降水序列对比发现,过去500年内青藏高原南部地区经历了相同的干湿变化过程,在年代际尺度上变化一致,可能受到相同的气候驱动因子控制.Tree growth/climate relationship was analyzed by the application of tree-ring-width proxy of Tibetan junipers （S. tibetica） at the Namlin Region. The results showed that annual precipitation was the controlling factor for radial growth at the study sites. Based on a linear regression model （the explained variance accounted for 45.94%）, an annual （from July of the previous year to June of the next） precipitation series from 1485 to 2010 were reconstructed and the reconstruction displayed remarkable climatic rhythms in decade scales for the Namlin precipitation series： relatively wet periods above the average occurred in 1490-1510, 1530-1550, 1620-1640, 1680-1720, 1740-1750, 1840-1850, 1880-1910, and 1960-1990 whereas relatively dry periods prevailed dur-ing 1520s, 1560-1610, 1650-1670, 1730, 1760-1830, 1860-1970, 1920-1950 and after 1990. Compared with Linzhou and the regional precipitation on the Southern Tibetan Plateau, both the dry and wet intervals contem-poraneously occurred in the decadal scales during the last 500 years, implying that the regional climate might be influenced by the similar climate dynamics.

关 键 词：降水 树轮 气候变化 青藏高原南部 

分 类 号：P467[天文地球—大气科学及气象学]