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间歇性阵流是山区小流域发生的黏性泥石流活动的基本形式,其输沙特性表现出一定的间歇性和涨落特性,其涨落可达均值的2~4个数量级。利用Hurst指数分析了蒋家沟近50年的数千阵泥石流观测资料,发现间歇性阵流的流量、径流量、输沙量序列的Hurst指数均大于0.5,说明序列具有一定程度的长程关联性。同时,对比阵流序列与洪峰序列,发现泥石流阵流的长程关联性强于洪峰序列。另一方面,输沙量的累积百分比均满足统一的指数分布形式:P(S)=CS~(-μ)exp(-S/S_c),其中μ越大意味着序列中输沙量较小的阵次越多;S_c表示的是阵流输沙的涨落情况,即S_c越大,阵流输沙的涨落越大。
Intermittent frontogenesis is the basic form of viscous debris flow occurring in small watersheds in mountainous areas. Its sediment transport characteristics show some intermittent and fluctuating characteristics, and the fluctuations can reach 2 ~ 4 orders of magnitude on average. Hurst index was used to analyze the data of thousands of debris flows in Jiangjiagou nearly 50 years. The Hurst indexes of flow, runoff and sediment load of intermittent flow were all above 0.5, indicating that the sequence has a certain degree of long-range correlation . At the same time, compared with the sequence of stream and flood peak, it is found that the long-range correlation of debris flow is stronger than that of flood peak. On the other hand, the cumulative percentages of sediment yield all satisfy the uniform exponential distribution: P (S) = CS ~ (-μ) exp (-S / S_c), where larger μ means less sediment load in the series The more the array; S_c said the fluctuation of sediment transport, the larger the S_c, the greater the fluctuation of sediment transport.