Feng Chen, Qing He, Ermenbaev Bakytbek, Shu-long Yu, Rui-bo ZhangClimatic signals in tree rings of Juniperus turkestanica in the Gulcha River Basin (Kyrgyzstan), reveals the recent wetting trend of high Asia

摘要

Drought variability of Kyrgyzstan is an important component of climate change of high Asia. Long-term information about the history of drought is, however, limited because the instrumental records are short. Here, we developed three chronologies for juniper trees (Juniperus turkestanica) under different microsite conditions in the Gulcha River Basin, Kyrgyzstan. The three chronologies (GUL, GUR and GUD) were compared with climate data which covered the study area. Growth of the GUL site correlates positively with May–June precipitation of the current growing season and September precipitation of the previous year, but negatively with temperatures of prior July, current May and July. Growth of the GUR site correlates positively with precipitation of current May and September, and negatively with temperature of current June and July. Ring width at GUD site is negatively correlated with temperature of the current May and July, and positively correlated with precipitation of prior December and current September. Response analysis shows that water availability is the main factor limiting the radial growth of juniper trees at the GUL and GUD sites. Based on the relationships derived from climate response analyses, the potential of tree-ring chronologies from this species to provide drought reconstructions in the Gulcha River Basin has been established. The GUL chronology and other moisture sensitive tree-ring series from high Asia capture the recent wetting trend. The records contribute to a　growing tree-ring network for high Asia, including sites in China, Kyrgyzstan, Pakistan and Tajikistan.Additional key words: Juniperus turkestanica, Kyrgyzstan, tree rings, climate response