The reserve comprises several types of lowland Amazonian forests, including igapo, varzea, and terra firme.

The Tapiche River basin in the area of the reserve exhibits a landscape containing alluvial plains and associated floodplains.

Swamps have developed on flat land and in depressions formed by fibric histosol soils with pH values varying between 3.5 and 5.

The Tapiche River has a strictly sub-Andean and origin, which eliminates a direct relationship with rainfall in the mountains.

Within the reserve there are small bodies of water (oxbows, channels, meanders, restingas and lakes) that communicate with each other and with the Tapiche River.

The cold spell is related to penetration of air masses coming from the southern polar latitudes and entering the South American tropics shortly after reaching Southeast Brazil.

The reserve is home to endangered species such as jaguar (Panthera onca), bald uakari (Cacajao calvus), giant armadillo (Priodontes maximus), the Brazilian tapir (Tapirus terrestris), the Amazonian manatee (Trichechus inunguis), and harpy eagle (Harpia harpyja).