The tropical rainforest biome of Biosphere 2 is 2000
sq. meters in area, and 28 meters high at its highest
reach. A simulated equatorial rainforest climate
supports plant species from the humid tropical regions
of the world. There are 8 distinct habitats created in
the Biosphere 2 tropical rainforest biome: lowland
rainforest, ginger belt, varzea, cloud bowl, mountain
(tepui), surface waters (including waterfall, splash
pond, pond, and stream), bamboo belt, and mountain
terraces.
The Biosphere 2 rainforest climate differs significantly
from a planetary rainforest. In particular, the annual
changes in day length are much greater in Biosphere 2,
with shorter winter days. Also, temperature ranges are
greater on both a daily and an annual basis. Although
Amazonian plant species dominate, the mix is eclectic
and the soils, though horticulturally adequate, are
created largely from local desert grassland materials
and do not closely simulate those of the wet tropics.
There are no close analogs for the Biosphere 2
rainforest on the planet. Thus, studies comparing
planetary rainforests with Biosphere 2 will have to be
carefully designed so that effects of different
environments and species can be clearly determined.