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利用青海省阿尼玛卿山地区祁连圆柏树轮宽度年表资料,分析树木生长与黄河上游唐乃亥水文站平均流量的关系,结果表明前一年8月到当年7月的平均流量与当年轮宽密切相关,相关系数为0.656,在此相关关系的基础上,重建了黄河上游过去1234年以来的流量变化.经11年滑动平均后曲线,定义流量低于均值1个标准差的时段为枯水期,流量高于均值1个标准差的时段为丰水期.在重建的黄河上游过去1234年流量变化中存在18个丰水期和12个枯水期,丰水期主要分布时段为:846～873年、1375～1400年,枯水期主要分布时段为:1140～1156年、1295～1309年、1473～1500年、1820～1847年.其中15世纪末是过去1234年以来黄河上游流量最低的时段,该时期青藏高原东北部发生了大范围的干旱现象.重建的流量变化包含较多的低频信息,枯水期与都兰、乌兰、德令哈等地树轮资料和其他代用指标记录的干旱期一致.多窗谱分析表明黄河流量变化存在2～5年,22年,35～38年,55～62年和114～227年左右的周期,其中最显著的是159和36年的周期.
The relationship between the tree growth and the average flow rate at the Tangnaihai hydrological station in the upper reaches of the Yellow River was analyzed based on the chronological data of the roundness of the Sabina przewalskii in the area of the Animaqing Mountains in Qinghai Province. The results showed that the average flow rate from August to July of the previous year was similar to that of the current year , The correlation coefficient is 0.656, on the basis of which, the flow changes since the upper reaches of the Yellow River have been rebuilt in the past 1234. After the 11-year sliding average post-curve, the periods of one standard deviation below the mean were defined as dry season, There was 18 wet periods and 12 dry periods in the 1234 upper stream of the reconstructed Yellow River, with the main distribution period of 846 ~ 873 and 1375 ~ 1400 years, the main distribution period of dry season: 1140 ~ 1156, 1295 ~ 1309, 1473 ~ 1500, 1820 ~ 1847. The late 15th century is the lowest flow in the upper reaches of the Yellow River since 1234, during which time the Qinghai-Tibet Plateau northeast A large range of drought occurred in the area.Reconstruction of traffic changes contained more low-frequency information. In dry season, it recorded with tree-ring data and other proxy indicators in Dulan, Ulan and Delinha The multi-window analysis showed that there was a period of 2 ~ 5 years, 22 years, 35 ~ 38 years, 55 ~ 62 years and 114 ~ 227 years in the Yellow River, of which the most significant ones were periods of 159 and 36 years .