Native name Rio Unini River mouth Rio Negro, Amazonas Source Amazonas Country Brazil | Main source Amazonas River system Rio Negro Mouth Rio Negro | |
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The Unini River (Portuguese: Rio Unini) is a river of Amazonas state in north-western Brazil. It is a right tributary of the Rio Negro.
Contents
Map of Rio Unini, Barcelos - State of Amazonas, Brazil
Course
The Unini River forms where the Água Preta stream joins the Preto River. It then flows east to the Rio Negro, forming 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 400 kilometres (250 mi) from its mouth to the headwaters. The basin covers about 2,689,644 hectares (6,646,260 acres). The largest tributaries are the Papagaio, Paunini and Solimõezinho streams.
The river has generally acidic water with little suspended material. The river and its tributaries make many meanders, creating great diversity of aquatic environments including lakes, rivers, creeks and flooded forests. The river is lowest between October and November, and highest between June and July. Water levels vary from minimum to maximum between 11.26 and 15.75 metres (36.9 and 51.7 ft).