Amazon Tours / Brazil – In principle, the
Amazon Rainforest biome
distinguishes two types of ecosystems:
aquatic ecosystems, representing about 5% of the biome's surface and
terrestrial ecosystems (95%).
Aquatic Ecosystems
Aquatic ecosystems can be divided into periodically flooded areas (
Várzeas) and permanently flooded areas (
Igapós).
These are plain areas of fluvial - sedimentary origin that margin the river banks.
Its
vegetation is denominated
Alluvial Dense Tropical Rainforest.
Despite relatively fertile soils, due to the vegetation's lack of capacity to adapt to the inundations, the flora diversity of this ecosystem is pretty low.
Gama / de Souza / Martins registered 181 tree species in
Várzea rainforests in the state of Pará.
Terrestrial Ecosystems
The terrestrial ecosystems, like
Terra Firme occupy most of the Amazon territory.
These are rainforests that never suffer inundation, occupying both, the
Amazon Basin
lowlands (above 50 m)
such as the
submontane scarps and plains of the highlands
(see also
Geology of the Amazon).
This ecosystem of the Amazon rainforest has countless adaptations to face the poverty of sediments and nutrients.
Its trees are able to fill up with nitrates through nitrogene - fixing bacteria which are connected to their roots.
Therefore, its flora diversity is elevated.
Gama / de Souza / Martins registered 1.192 tree species in
Terra Firme rainforests in the state of Pará
– Ecotourism in Brazil / Amazon.
