Overview
The Unini River () is a river located in the Amazonas state in north-western Brazil. It serves as a right tributary of the Rio Negro.
Course
The Unini River originates from the confluence of the Água Preta stream and the Preto River. From there, it flows eastward towards the Rio Negro, serving as the border between the Rio Unini Extractive Reserve to the north and the Jaú National Park to the south. The river basin has about 1,500 streams and over 1,000 lakes, with an estimated length of from its mouth to the headwaters. The basin covers approximately . The largest tributaries are the Papagaio, Paunini and Solimõezinho streams. The Unini River is characterized by its generally acidic water with minimal suspended material. Its meandering course, along with its tributaries, gives rise to a diverse array of aquatic environments, including lakes, rivers, creeks, and flooded forests.
Water levels in the river exhibit seasonal fluctuations, with the lowest levels typically occurring between October and November, and the highest levels between June and July. The range of water levels varies from minimum to maximum between .
See also
*List of rivers of Amazonas