A 140-year record of environmental changes in Sao Sebastiao, Brazil

Author(s)

Padua, Patricia Cedraz ; Srivastava, Priyeshu ; de Martini, Ana Paula ; Alves, Daniel P., V ; Gabel, Victor Schneider ; de Lima Ferreira, Paulo Alves ; Jovane, Luigi

• Document type: Journal article
• Source: Science of The Total Environment; v. 838, p. 14-pg., 2022-06-14.

Abstract

Over the past two centuries, coastal and estuarine areas have experienced environmental stress due to rapid population growth, leading to higher demand, overexploitation, habitat transformation, and pollution, which have severe consequences on the overall ecosystem and human health. This work aims to understand historical perspectives of such environmental stress in a coastal area of Sao Sebastiao city in the Sao Paulo State of Brazil, which has witnessed rapid changes in land use over the past 60-70 years. We collected eleven surface sediments and one 64 cm long core from the shallow water depth sector of the Sao Sebastiao Channel (SSC), adjacent to the Araca Bay region. Sediments were dominantly composed of terrestrial siliciclastic material carrying signatures of both local inputs (i.e., weathered granitic and gneissic rocks of Serra do Mar Mountain ranges) and Plata Plume sediments brought by Brazilian coastal currents. Low sediment accumulation (avg.= 0.10 cm yr(-1)) between 1880 and 1947 showed a stable environment followed by an abrupt increase in sedimentation (avg. = 0.84 cm yr(-1)) from 1947 to 2017. This approximate eight-fold increase in sedimentation after 1947 marked significant anthropogenic changes in the region, which is coincidental with major changes in land use through the construction of the port of Sao Sebastiao (1930s) and BR-101 Highway (1980s). While recent surface sediments showed no pollution of heavy metals, anthropogenic Zn enrichment was found between 1880 and 2000. Zn enrichment was from the combined sources, e.g., agriculture activities, domestic sewage, and possibly Zn coated ship paints. Our study also indicates that planned future expansion of Sao Sebastiao portmay further increase the sedimentation rate in SSC and impact the ecosystemof Araca Bay and SSC. (AU)

• FAPESP's process: 16/24946-9 - Sea-level changes and Global Monsoon System: clues from marine cores in Brazil
• Grantee: Luigi Jovane
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants
• FAPESP's process: 19/11364-0 - Investigating ocean acidification during the late Maastrichtian and early Danian from marine sections of Brazil and India: Implications for impact vs. volcanism roles in the Cretaceous-Paleogene boundary mass extinction.
• Grantee: Priyeshu Srivastava
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/17061-6 - Relationship between environment and magnetotactic bacteria
• Grantee: Luigi Jovane
• Support Opportunities: Research Program on Global Climate Change - Regular Grants