早全新世沙沟河古洪水沉积及其对气候变化的响应

对沙沟河一级阶地河漫滩ZJDZ剖面中360个样品的粒度,矿物的成分含量及pH值等沉积特征进行分析,并对关键层位进行了一共6个¹⁴C年代测定。结果表明:10.9~4.0 ka B.P.期间沙沟河发生多次大规模洪水,10.9~7.0 ka B.P.期间沙沟河发生20次左右大型洪水,洪水重现期为0.40 ka,其中,10.9~9.0 ka B.P.期间洪水的规模逐次增加,9.0~7.0 ka B.P.期间洪水的规模有所减小;7.0~4.2 ka B.P.期间至少有过4~5次大型洪水,洪水的重现期为0.71 ka。洪水事件主要发生在比较湿润的气候背景下,高频率洪水事件的发生与气候频繁的干湿波动有关。     

Characteristics of DDF at Baishui Glacier No.1 Region in Yulong Snow Mountain

Based on observed mass balance and meteorological data since September 2008 and ablation data by the expedition team of Tibetan plateau from June to August 1982 at Baishui(白水) Glacier No.1 region,we analyzed the spatial and temporal changes of degree-day factor(DDF) of the Baishui Glacier No.1 following the changes of space,time,and temperature,which lays a theoretical foundation to establish DDF model.The results indicate that the melting DDF of ice showed a significant down-ward trend with rising temperat...