A REVIEW OF USE OF GIS FOR THE EVALUATION OF HEAVY METAL AND WATER QUALITY PARAMETERS IN THE CANAL DO CUNHA WATERSHED AND WEST OF THE GUANABARA BAY, RIO DE JANEIRO (BRAZIL)

As well as other sub-basins of the Guanabara Bay, the Canal do Cunha watershed, located in the Rio de Janeiro city, has suffered severe environmental degradation since the 50s, due to accelerated urban-industrial development. The fluvial dynamics has changed by the deforestation, landfill constructions, drainage and vale occupation. Canal do Cunha deliver wastewaters and sediments at the western side of Guanabara Bay. Contribute to the environmental degradation and has direct influence on the water quality indexes and heavy metal contamination at the western side of Guanabara Bay. This study intends to evaluate, through geoprocessing techniques, the spatial distribution of Lead (Pb), Zinc (Zn), dissolved oxygen (DO) and total phosphorus (total P) concentrations and pH values, using data provided by six monitoring stations of the Instituto Estadual do Ambiente - INEA (State Environmental Institute). This work allows to observe the influence of weather conditions on Pb and Zn concentrations in superficial waters and surface sediments and the behavior of DO, pH and total P of superficial waters before and after the implementation of the remediation program: Programa de Despoluicao da Baia de Guanabara (PDBG; Pollution Remediation Program of Guanabara Bay). Canal do Cunha flow has direct influence on the low quality indexes of water and contributes to the heavy metal contamination and environmental degradation of the western region of Guanabara Bay.