When comparing the vertical structure of terrestrial and aquatic biomes, what is the main difference?

Terrestrial biome includes land ecosystems such as forests, desserts, etc whereas aquatic biome includes aquatic ecosystems such as  ponds, sea, oceans, rivers, etc. Both the biomes have vertical stratification.
Vertical structure of terrestrial and aquatic biomes differ from each other. Vertical structure in terrestrial biome has the forest floor that includes root and soil layers whereas aquatic biome consists of vertical structure that depends on abiotic factors such as light, temperature, salinity, pH, etc.

That is true! many fish species traveled to the u.s. because of it.