1. Weather and sea conditions: Pazhou Bay is located in the bay area and is greatly influenced by the marine climate. Natural factors such as wind, waves and tides will affect the river course, leading to vacillation.
2. Geology and topography: The topography and geological conditions around Weizhou Bay will also affect the stability of the river. For example, earthquake, soil settlement and other factors will lead to the deformation or settlement of the river, which will lead to the sway of the river.
3. Material and surface properties: When the river flows along the surface of the object, the material on the surface of the object may affect the straightness of the water flow. For example, some hydrophobic substances may be attached to the surface of the object, which will cause the water to flow in a straight line, thus causing the river to sway.
Please note that the above are just some possible reasons, and the actual situation may be more complicated. If more detailed or professional information is needed, it is recommended to consult geographers or experts in related fields.