DISENTANGLING THE EFFECTS OF PULSE DISTURBANCES FROM LANDSCAPE MODIFICATIONS IN AN IRON ORE TAILING CONTAMINATED TROPICAL RIVER

The Paraopeba river is an important water resource in Brazil, influenced by the country’s third most populous area, the Belo Horizonte Metropolitan Region (BHMR). In January 2019 a mass deposition of iron ore tailings affected the river bed. Here, we present a data-driven approach to disentangle the effects of pulse disturbances, caused by the deposition and the seasonal remobilization of iron ore tailings, from the effects of anthropogenic landscape modification on the BHMR. Historical data was used to determine the environmental signatures of the ore tailings deposit (enrichment in iron and manganese) and the BHMR (water conductivity, oxygen concentration, and fecal bacterial indicators) in the Paraopeba water. Despite the geographical coincidence, different microbial consortia can be associated with the ore tailings and with the BHMR. Interannual and seasonal variations on manganese concentrations in the water are consistent with the expectation of a pulse disturbance, with a downstream displacement of the environmental signature. Our results highlight the importance of continuous surveillance of water bodies for the determination of impacts due to environmental disasters, enabling the quantification of the effects of pulse perturbations even in the presence of other anthropogenic pressures in the river landscape.

Presentation Preference: Oral

Primary Presenter: Arthur Silva-Lima, Universidade Federal do Rio de Janeiro (arthurwlima@gmail.com)

Authors:

Arthur Silva-Lima, Universidade Federal do Rio De Janeiro  (arthurwlima@gmail.com)

Bruna Paiva, Universidade Federal do Rio De Janeiro  (paivabmagalhaes@gmail.com)

Carolina Dias, Universidade Federal do Rio De Janeiro  (carolbiomar@gmail.com)

Larissa Galvão, Universidade Federal do Rio De Janeiro  (larissalucateli24@gmail.com)

Paulo Hargreaves, Universidade Federal do Rio De Janeiro  (pauloihc@yahoo.com.br)

Marcio Tenorio, Universidade Federal do Rio De Janeiro  (marcio.tenorio@gmail.com)

Paulo Salomon, Universidade Federal do Rio De Janeiro  (pssalomon@gmail.com)