随着珠江河口地区滩涂岸线资源开发和涉水工程建设,河口边界形态及动力环境产生了巨大的变化;动力环境变化必然引起河口河床形态的调整,对潮汐河口稳定产生深远的影响。以珠江河口潮汐通道稳定性分析为基础,探讨潮汐河口的河相关系,初步提出了河口潮流变化控制指标。研究建立了珠江河口口门断面面积与多年平均落潮流量之间的关系,并建立了近期口门均衡断面的河相关系;在此基础上,预测了河口潮流变化引起的口门河床冲淤变化。根据河床冲淤变化与口门行洪能力调整的关系,提出了河口口门落潮流量变化控制指标为1%~2%,研究成果为河口涉水工程管理提供了定量指标参考。

Along with the exploitation of tidal flat and beach resources and the construction of water projects in the estuary region of the Pearl River, the estuarine boundary shape and dynamic environment changed greatly, which inevitably gave rise to the adjustment of estuarine riverbed morphology, exerting far-reaching influence on the stability of tidal estuaries. On the basis of stability analysis for the tide channel of Pearl River estuary, the hydraulic-geometric relation and the tide control indicator were put forward. Moreover, the relationship between entrance section area and average ebb flow for many years of the Pearl River estuary was established. The balanced section’s hydraulic-geometric relation was also established. On this basis, scouring and silting at the entrance caused by estuarine tide changes was forecasted. According to the relationship between riverbed sediment adjustment and flood discharge capacity change, we concluded that the ebb flow change at the entrance of the estuary should be controlled in 1%-2%. The research result provides quantitative reference for the management of water projects at the estuary.