Different types of environments resulting from the dynamic equilibrium between the sea, the river and freshwater can be found in the Baix Ter plain. The interaction between the sea, the river and the sediments it carries has given rise to a wide variety of ecosystems, with very subtle variations in the duration of floods, depth, salinity, nutrient content or type of substrate. The variety of environments and the diversity of organisms that can be found in them are two of the most important ecological aspects of the area. A description of the main aquatic ecosystems found in the Baix Ter follow.


- marshlands and coastal lagoons
- coastal freshwater ponds
- springs
- inland temporary ponds
- river Ter estuary


- strongly humanized aquatic environment

Intensive agricultural and herding activities are possible thanks to high fertility and ease of irrigation in the Lower Ter plain. As a result we find a characteristic landscape with aquatic environments created or modified by man. Although they are man-made it does not mean that they do not have an important paper as a refuge for aquatic fauna and flora.
Extended rice fields, with summer flooding, result in an accumulation of birds. We can also find enclosures (fields ‘closed’ by trees) and pasture lands, easily ploughed in these flooded lands. Although they are quite scarce they support species of flora and fauna characteristic of temporary environments.
The plain has an extensive system (over 1000km in length) of streams and irrigation ditches that drain rainwater and/or canalise irrigation waters.

White herons pecking in a rice field