If you were to walk from the sand dunes toward the sea on a sandy beach, you would likely notice a number of changes in the nature of the beach.
As you first approach the sand dunes, the sand may be loose and granular, and you may notice a variety of plants and wildlife in the area. The sand dunes themselves may be tall and steep, and may be covered in vegetation such as grasses or shrubs.
As you walk closer to the water, the sand may become more compact and harder, and the dunes may become less steep and more gradual. You may also notice that the vegetation becomes less dense, as the salt and wind from the sea can make it difficult for plants to survive.
As you approach the water's edge, the sand may become wet and packed down, and you may see evidence of the tide's movement, such as tide pools or seaweed. The water may be clear and calm, or it may be rough and choppy depending on the weather conditions.
As you move further into the sea, the sand will disappear and will be replaced by rocks, coral reefs or other forms of marine life. The water will become deeper and the sea creatures will become more diverse and abundant. Depending on the location, you may also encounter waves, currents, and tides that create a dynamic and ever-changing environment.
Overall, the sandy beach will change from a relatively stable and protected environment with a rich biodiversity on the dunes side to a dynamic and ever-changing environment with a less diverse but rich in marine life on the sea side.