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
Scattered
throughout the alluvial plain we find deep, circular ponds filled
with underground water. They are usually formed by landslides that
leave on the open the phreatic levels and result in water surfacing.
Although years ago these ponds abounded most of them have now disappeared.
The best preserved ones can be found in Pals.
Since their water comes from underground its levels and composition
varies very little and the nutrient content is very low; they are
clean and clear waters in which herbaceous beds of submerged macrophytes
(aquatic plants that require clear waters in order to grow) thrive.
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Ullals
de Pals |
- inland temporary
ponds
- river
Ter estuary
- strongly
humanized aquatic atmospheres
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