Aquatic ecosystems

2. the natural home or environment of an animal, plant, or other organism.
3. a small, narrow river.
6. of, found in, or produced by the sea.
8. of or found in fresh water; not of the sea.
10. an area of ocean that is far from land
13. an area or ridge of land that separates waters flowing to different rivers, basins, or seas.

1. a large body of water surrounded by land.
4. an area of low-lying land which is flooded in wet seasons or at high tide, and typically remains waterlogged at all times.
5. a large natural stream of water flowing in a channel to the sea, a lake, or another such stream.
7. the tidal mouth of a large river, where the tide meets the stream.
9. of or denoting the area of a seashore which is covered at high tide and uncovered at low tide.
11. a small body of still water formed naturally or by hollowing or embanking.
12. reef a ridge of rock in the sea formed by the growth and deposit of coral