In the plain of the Baix Ter they appear different types from atmospheres related to the water, that are from the dynamic balance between earth, sea and fresh water. The interaction between the sea, the river and the sediments that this transports has formed a very diverse mosaic of ecosystems, with very subtle variations in the duration of the flood, the depth, the salinity, the content of nutrients or the type of substrate. Next the main aquatic ecosystems are described that are in the Baix Ter. The variety of atmospheres and the diversity of organisms that lodge are one of the main ecological values of these humid zones.


- marshlands and coastal lagoons
- coastal freshwater ponds
- springs
- inland temporary ponds


- river Ter estuary

The river is the most important thing in the plain. Sedimentation associated to the river has given rise to the actual orography of the plain and together with marine dynamics is the only responsible for the creation of the different aquatic environments that can be found in the area. The last stretch of the river is canalized and it is quite difficult that in a near future the riverbed suffers any natural modifications. The last stretch also acts as a typical Mediterranean estuary, where the mixture of freshwater with seawater creates variable salinity and nutrient conditions. For example, when the volume is low seawater penetrates into the estuary. On the other hand when the water volume is high the influx of nutrients from the river is very important for the sustenance of marine communities of the Illes Medes.

Ter river

- strongly humanized aquatic atmospheres