Guanabara Bay ecosystem health report card: Science, management, and governance implications

Abstract

Guanabara Bay, a natural tropical embayment in Southeast Brazil adjacent to Rio de Janeiro, is important to the Brazilian economy as it provides areas for shipping, industry, recreation, and tourism. But commercial and residential urban development in the watershed results in water quality degradation. In Guanabara Bay, strong water quality gradients as a function of inputs and tidal flushing were evident. In the watershed, the urban and industrial areas degraded stream water quality, and the best water quality was in the upstream, rural areas. Steps have been initiated to collect or contain litter (ecoboats and ecobarriers) and reduce sewage discharge (sewage treatment plants). In spite of this, urban development continues to degrade Guanabara Bay ecosystem health. Large-scale international events hosted by Rio de Janeiro have brought widespread attention to Guanabara Bay pollution issues. Management actions have been identified to improve Guanabara Bay ecosystem health, including establishing a strong governance structure, restoring water quality in the rivers, bay and beaches, restoring habitats in Guanabara Bay and its watershed, and mitigating for climate change impacts. An ecosystem health report card was generated using monitoring data with stakeholder engagement for both Guanabara Bay and its watershed. The scientifically rigorous and transparent report card process can be used to track Guanabara Bay restoration progress.