Jamanxim River Jamanxim River The Jamanxim River is a river of Pará state in north-central Brazil. Originating in the Serra do Cachimbo, it is a tributary of the Tapajós, into which it flows a few kilometers upstream from Itaituba. The river flows through the Tapajós-Xingu moist forests ecoregion. It flows through the Itaituba I National Forest, a sustainable use conservation area established in 1998. The river basin also contains part of the Rio Novo National Park, a conservation unit created in 2006. Its hydroelectric potential, along with that of the Tapajós, was assessed by Eletronorte (Centrais Elétricas do Norte do Brasil S.A.),
Tapajós-Xingu moist forests the ecoregion blends into the Mato Grosso seasonal forests ecoregion. Elevations range from above sea level along the Amazon to in the south. The ecoregion mostly lies on the undulating terrain of the ancient Brazilian Shield. Soils are often rich in nutrients, but poor soils are found in the higher areas. The main rivers are blackwater, with little or no suspended sediment. The largest is the Iriri, a tributary of the Xingu. Others are the Jamanxim, Curuá, Crepori, Curuá Una, and Jaraucu. The ecoregion is in the neotropic ecozone and the tropical and subtropical moist broadleaf forests biome. The Köppen