Why do trees by the water fall to the surface to grow

 　　We know that plants are phototropic, but is there still water? It does, but only the root tendencies are evident. Normally, a plant's roots grow downward by gravity (geotropism), but when the water in the soil is unevenly distributed, the roots grow toward the side with high water content.

　　Since hydrotropism is a characteristic of roots, why does the trunk fall to the surface? One speculation is that this is actually a manifestation of plant phototropism, because the side near the water tends to be more open and has more light, so trees will grow to that side, and some trees on the edge of dense forests also tend to grow slantingly to the outside. Another possibility is that the soil on the water side has been eroded by water for a long time, making trees prone to fall to that side.