MANAUS, Brazil — It’s September, near the peak of 2023’s extreme drought in the Brazilian Amazon, and José Clodoaldo de Oliveira keeps an eye on the GPS as he pilots the voadeira, a small aluminum boat, in the Mariuá Archipelago along with two fellow researchers, while watching out for exposed sandbanks and rocks. This is Earth’s largest fluvial island chain. It sprawls across 360 kilometers (220 miles) in the Middle Negro River, the Amazon River Basin’s second-largest tributary. Here, we find ourselves in a labyrinth of more than 1,400 islands, flooded forests, rivers, lakes and sandy beaches — with no signs of civilization in several stretches. The Negro is a well-preserved backwater river chosen by scientists from the applied chemistry research group at Amazonas State University (UEA), to develop the Amazon Basin’s first water quality index (WQI) to evaluate water bodies’ state of health and guide public policies and scientific studies. Near the shore in the Mariuá Archipelago, pink river dolphins swim up and down hunting for fish; a cayman glides toward a small strip of sand; capuchin monkeys leap from tree to tree; swarms of butterflies rest on a rock, peppering it white and yellow. “The Negro is a beautiful river, but it also has its anthropogenic problems,” Oliveira, a 54-year-old geographer finishing his master’s degree in water resources, tells Mongabay. In the Middle Negro, he says, municipalities like Barcelos and Santa Isabel do Rio Negro discharge their untreated wastewater directly into the river. “So far, the Negro has…This article was originally published on Mongabay
The post Study to benchmark water quality finds key Amazon tributary in good shape first appeared on EnviroLink Network.