基于树轮宽度的伊塞克湖入湖径流量重建与分析

中亚区域气候与水文变化特征及其对全球气候变化的响应重要而复杂，伊塞克湖流域周边山区分布的天山云杉原始森林为揭示区域过去几百年气候水文变化事实和规律提供了良好的载体。本文利用伊塞克湖周边山区4个点的树木年轮宽度、入湖年径流量以及CRU格点气象资料，基于对树轮宽度指数对区域水文和气候要素响应关系分析，利用区域树轮宽度差值年表重建了伊塞克湖355a来的入湖径流量变化历史，二者线性转换方程的方差解释量为30．2％。重建径流量的丰枯阶段变化与天山北坡的玛纳斯河、乌鲁木齐河相对应。但与天山南坡的阿克苏河流域的径流量的低频变化特征不一致，在1850年前的变化趋势相反。空间相关分析发现伊塞克湖流域重建径流量变化能较好地代表中亚天山北坡以及哈萨克斯坦东南部和新疆北部平原区降水变化。此外，还发现了伊塞克湖径流量与北大西洋长周期年代际震荡（AMO）在年代际尺度的同步变化。

Tree-ring width based runoff reconstruction and analysis of Issyk-Kul Lake

Hydroclimate change and its response to global change is important and complex in Central Asia, and spruce forest which is widely distributed around Issyk-Kul Lake Basin provide perfect proxies for past hydroclimatic information in the past several centuries. Tree-ring width data, runoff and grid data from Climate Research Unite around Issyk-Kul Lake were collected. Based on the evaluation of the hydroclimate information capacity of tree-ring width, the 355 a runoff history in Issyk-Kul Lake basin was reconstructed by using tree-ring width residual chronology. The drought and flood period in the reconstructed series is well consistent with that in Manasi River, Urumqi River and Iily River from north slope of Tianshan Mountains, but not consistent with that in Akesu River from southslope of Tianshan Mountains. Spatial representation analysis revealed the reconstructed runoff captured large scale precipitation change in north slope of Tianshan Mountains and the plain area in north Xinjiang and southeast Kazakhstan. In addition, the low frequency change trend was also consistent with Atlantic Multi-decadal Oscillation (AMO).