A landscape is an image featuring an expansive view without any humans dominating the scene, a photograph of natural scenery with land and sky-based elements displayed in a pictorial fashion. It may include evidence of man, people, animals, even part of the sea providing that none of these additional elements dominate the photograph.
A seascape is a photograph of natural coastal scenery, a wave study, or a picture of the open sea, provided always that the sea is the centre of interest of the photograph. People, boats, and man-made structures may be present as incidental to the photograph.