What is the location of the ocean ecosystem?

The ocean's ecosystem is affected by a number of locations; obviously, the most clear cut one are the world's oceans themselves (Arctic, Pacific, Atlantic, Indian (and, although it's debatable, the Southern, as well.)) However, the atmosphere and land plays a huge role in maintaining the ocean's ecosystem. As I'm sure you know, the water cycle plays a huge role in the distribution of water on land, in the ocean, and in the atmosphere. Therefore, although the oceans are the only locations of the oceanic ecosystem, many other places affect it.