天山北坡玛纳斯河355a来年径流量的重建与分析

玛纳斯河树轮年表序列与该河肯斯瓦特水文站年径流总量相关显著,使用5个树轮年表序列较好地重建出天山北坡玛纳斯河肯斯瓦特水文站355a来的年径流总量,解释方差达61%.355a重建流量变化表明:1)玛纳斯河年径流总量355a来大致经历了11个偏枯水期和10个偏丰水期,最长的偏丰水期为1670-1699年,持续了30a,最长的偏枯水期为1949-1994年,持续了46a;2)最显著的两个百年流量变枯趋势为1872-1995年和1671-1775年,径流量减少率分别为0.19×10⁸m³·(10a)^-1和0.26×10⁸m³·(10a)^-1;3)在1711-1712年、1872年重建流量发生过两次突变,前者年径流量由多到少突变,后者相反;4)重建流量最丰水的年代为17世纪80-90年代,比现今偏多17.9%～18.1%,最枯水的年代为19世纪60年代,比现今偏少16.7%;5)重建流量存在着58～59、9.6、27.2、16.9、4.8、4.3、2.9～3.0a的变化周期.

Reconstruction and Analysis of the 355 a Runoff of the Manas River on the North Slopes of Tianshan Mountains

Correlation analyses show that correlation between the series of the tree-ring chronologies from the Basin of Manas River and the annual runoff at Kensiwate Hydrological Station of the Manas River is significant and the best single correlation coefficient is 0.524, with a significance level of 0.0002. Using five series of tree-ring standard chronologies, a 355-year series of annual runoff can be reconstructed for Kensiwate Hydrological Station of the Manas River on the north slopes of Tianshan Mountains, with an explained variance of 61%. Verification from statistical parameters and independent reconstructed runoff data shows that the series of annual runoff reconstructed for the past 355 years is reliable. Analysis of the 355-year reconstructed runoff features indicates: 1)There were 11 periods below long-term mean and 10 periods above long-term mean. Among them, the longest period above mean was from 1670 to 1699, lasting 30 years, and the longest period below mean was from 1949 to 1994, lasting 46 years. 2)There were two drying periods with the highest significance, lasting more than 100 years, from 1872 to 1995 and from 1671 to 1775, with runoff decreasing rates of 0.19?10⁸ m³·(10a)^-1 and 0.26?10⁸ m³·(10a)^-1, respectively. 3)There were two abrupt changing periods from 1711 to 1712 and in 1872, the former changing from more to less, but the latter changing from less to more. 4)There were two rich-water decades in the 1660s and the 1670s, with a runoff of 17.9~18.1% more than that at present (the mean is 12.19?10⁸ m³ from 1956 to 2000), and one short-water decade in the 1860s, with a runoff 16.7% less than that at present. 5)The reconstructed runoff has 58~59, 9.6, 27.2, 16.9, 4.8, 4.3, 2.9~3.0 years variation quasi-periods.