感潮河段水位过程的差异直接影响到两岸易涝区涝水的外排进程,对感潮河段水位与上游洪水和河口潮位进行关联性分析,旨在为感潮河段两岸易涝区治涝合理选取设计潮位过程提供依据。本文构建的感潮河段水位与上游洪水、河13潮位的关联性分析模型,首先采用Copula函数分别构建感潮河段年最高水位与上游相应洪水和河口相应潮位的联合分布,再基于联合分布提出关联性分析模型。选取珠江三角洲磨刀门水道的竹银站来分析其水位与上游马口站洪水和河口三灶站潮位的关联性。分析结果表明:(1)对任一重现期竹银站最高潮位,与马口站流量遭遇的概率显著低于与同一重现期的三灶站高潮位遭遇的概率,即竹银站出现高潮位时,受河口潮位影响的概率要大得多;(2)对一确定重现期竹银站最高潮位,与马口站流量组合的风险并不一定低于与同一重现期三灶站高潮位组合的风险,当重现期较大时,前者高于后者。
The difference of water level process in the tidal river will directly affect the drainage process of the waterlog-prone area on both sides of the tidal river. The correlation of the water level of the tidal river with upstream flood and estuary tide level was carried out in order to provide basis for proper selec- tion of the design tidal level process of the tidal river for defensing waterlogging of the waterlog-prone ar- ea. The model about the correlation of the water level of the tidal river with upstream flood and estuary tide level is established. At first, the different copula function is used to build the bivariate joint distribu- tion of the annual maximum water level of tidal reach and its corresponding upstream flood discharge, as well as the annual maximum water level of tidal reach and its corresponding estuary tidal level. Then based on them, the correlation analysis models are put forward. The case study on the correlation of the water level in Zhuyin observing station of Modaomen water channel with upstream flood in Makou observing station and estuary tide in Sanzao observing station, one of the Pearl River's main sea-entering channels, is conducted and the results are as follows: (1) For any annual maximum water level of Zhuyin observing station, the probability meeting with flood in Makou observing station is much lower than meeting with tide level of the same recurrence interval in Sanzao observing station, i.e., for the water level of Zhuyin observ- ing station, the influence of tide level Sanzao observing station is much greater. (2) For any annual maxi- mum water level of Zhuyin observing station, the risk probability combining with flood in Makou observing station is not always less than that combining with tide level of the same recurrence interval in Sanzao ob- serving station. When recurrence interval is large, the former is higher than the latter.