珠江三角洲网河区径流潮流相互作用分析

Interaction of fluctuating river flow with a barotropic tide in river network of the Zhujiang Delta

在大量实测资料基础上采用小波分析方法对珠江三角洲网河区径流与潮汐的相互作用进行分析,得出如下结果:网河区潮差和潮位的周期变化既有典型潮汐的半日周期和全日周期以及半月周期,也有径流量的周期变化如64 8d的周期变化,即同时具有径潮的周期变化.不同河段潮差及各分潮波振幅与径流量的大小具有明显的反相关关系,径流量越大,潮差越小,三水站潮差随流量以-0 0002的速度减小,网河区下游河段则减小得较慢.上游径流量越大,因克服径流的阻碍作用而消耗的能量越大,潮汐作用强度迅速减弱,各分潮潮波振幅和潮差沿程减小越快.随着径流量的增大,三水站潮簇D1,D2和D4的振幅明显减小,D2的振幅衰减得最快.

Based on lots of observation data, the interaction of fluctuating river flow with a barotropic tide was analyzed by wavelet transform. It can be concluded that the periodic variation of tidal range and water level has both typical semidiurnal and diurnal and semi-monthly period of tide, and 64.8 d period of river runoff, which indicates that water level of the Zhujiang Delta is controlled by tide and river flow. The inverse correlation between tidal amplitude of different river-ways and river discharges is significant and the more river discharge the less tidal amplitude and tidal range; the tidal range of Sanshui Station decreases with river discharge about at 0.000 2 velocity but more slow in lower reaches of the Zhujiang River Delta. It is indicated that the tidal effect intensity and the tidal range decrease rapidly along river-way because the consumed tidal energy for overcoming the resistance of river discharge increases with increasing river discharge in upper reaches; the partial tide such as D_1, D_2 and D_4 of Sanshui Station decreases significantly with increasing river discharge, but the amplitude of D_2 reduces more quickly.