Michel Braunstein Underwater Photography

The source of the Rio Negro (Black River) in Colombia, continuing its journey to Brazil, through the rich Amazonian forest. Here it converges with the Rio Solimões to form the Amazon. From afar, the Rio Negro appears to be black but from a closer look, it is actually dark brown. This dark color is due to the humic acid which forms due to the incomplete decomposition of the phenol contained in the vegetation of the sandy clearings.