The first one conceptually create a framework, kinds of like a window, to let people see the wave of the water through it. Moreover, I understand it in a more architectural way, which means I personally feel like the water becomes one of the various materials in the landscape and by combined all kinds of different materiality, such as, water, steel fence, rock and gravel, even water plants near by the water, the landscape in the waterfront is so elegant and artistic.
The second is simply showing the other stuffs following the water so that in this case, water becomes a tool in landscape to help other stuffs floating, moving and showing their relationships with water.
Next, the designer intend to build a natural way of landscape as possible as they can. They rise up the trees to let people are able to see the manmade waterfall without any obstacles. And the role of water here is to be the natural elements in this small landscape.
Last one is quite interesting. It was taken at Brooklyn Bridge Park and in that area, the landscape designer built all installations and walk way, ect. around it but kept a long way raw stones and lichen on purpose. They preserve a certain area and kept it original to let the river water comes in and out through seasons then built a walkway on and around it. In this case, water becomes not only an element to bring people back to nature but also a seasonal sign for people to watch, which means the level of the water surface is changing.