Response of Different Altitude Vegetation to Climate Change in Taibai Mountain Alpine Zone during the Past about 2000 Years

YANG Xiuyun1, GAO Yishen1, CHENG Ying1,2, WANG Hongya1,†, LIU Hongyan1

1. Schoolof Urban and Environmental Sciences, Peking University, Beijing 100871; 2. School of Geography and Tourism, Shaanxi Normal University, Xi’an 710119; † Corresponding author, E-mail: why@urban.pku.edu.cn

Abstract Based on organic geochemical indicators of a lake-sediment profile from Western Foye Chi (3410 m), the study reconstructs the climate change of the Taibai Mountain alpine zone during the past about 2000 years. In order to explore the similarities and differences of vegetation response to the climate change at different altitudes in the alpine zone, pollen analysis of the profile was carried out, and cluster analysis was performed on the results in combination with the published pollen data of Paomaliang (3556 m), Sanqingchi (3080 m) and Fangxiangsi (3000 m) in Taibai Mountain. These analyses suggest that the responses of the vegetation to relatively cold and dry climate have good consistency at different altitudes, which is even more noticeablein the transition zone of timberline. Besides, along with the modern warming period, the responses of vegetation to climate change are mainly determined by the altitude. This study can provide some references for understanding the coupling relationship between climate and vegetation of alpine environmental systems during the Late Holocene. Key words Late Holocene; Taibai Mountain; alpine zone; pollen analysis; responses to climate

在过去的近2000年中, 发生中世纪暖期、小冰期以及近百年升温等典型气候事件, 各种载体记录的古气候信息非常丰富[1‒3]。了解过去的气候‒环境特征, 有助于更好地认识当今全球气候问题, 预测未来气候变化。因此, 建立过去2000年高分辨率环

境记录的有关研究受到越来越多的关注[4‒5]。

湖泊对气候变化响应敏感, 在过去全球变化及区域响应差异的研究中具有不可替代的优势[6]。秦岭主峰太白山是中国大陆中东部(105°E以东)的最高峰, 位于东亚季风区。由于全新世升温, 太白山