Technological Hazard Vulnerability: A GIS-Based Approach for Supporting Environmental Zoning

Technological hazard assessments are extremely rare in Brazil, despite their importance for planning. Aquatic systems are of particular concern, since they are the endpoint of every process occurring in the watershed, including technological disasters. Thus, our goal is to map the technological hazard vulnerability in lagoon systems though a geographic information systems (GIS) model. The technological hazard vulnerability model consists of the spatial overlapping of technological pressure and fragility, having environmental systems as spatial units. The methodology was applied to the lagoon systems of the Rio Grande do Sul State, Southern Brazil, as a case study. The very high vulnerability of the Northern Guaíba Lake is due to the high concentration of technological infrastructures combined with high fragilities of wetland systems. In the Patos Lagoon Estuary, highly vulnerable systems consist mostly in shallow waters. The Mirim Lagoon was less vulnerable compared to other systems, due to a much smaller occurrence of elements of technological pressure. The proposed methodology allowed for the identification of environmental systems particularly vulnerable to technological hazards, where management efforts must be more intense. The results were used for the Ecological-Economic Zoning of the Rio Grande do Sul, as well as to revise the water quality framework of the Patos Lagoon estuary, currently underway. Integr Environ Assess Manag 2021;17:445-454. © 2020 SETAC.