Long-term effects of oil pollution in mangrove forests (Baixada Santista, Southeast Brazil) detected using a GIS-based multitemporal analysis of aerial photographs
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
04/11/2013
04/11/2013
2012
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Resumo |
Oil spills are potential threats to the integrity of highly productive coastal wetlands, such as mangrove forests. In October 1983, a mangrove area of nearly 300 ha located on the southeastern coast of Brazil was impacted by a 3.5 million liter crude oil spill released by a broken pipeline. In order to assess the long-term effects of oil pollution on mangrove vegetation, we carried out a GIS-based multitemporal analysis of aerial photographs of the years 1962, 1994, 2000 and 2003. Photointerpretation, visual classification, class quantification, ground-truth and vegetation structure data were combined to evaluate the oil impact. Before the spill, the mangroves exhibited a homogeneous canopy and well-developed stands. More than ten years after the spill, the mangrove vegetation exhibited three distinct zones reflecting the long-term effects of the oil pollution. The most impacted zone (10.5 ha) presented dead trees, exposed substrate and recovering stands with reduced structural development. We suggest that the distinct impact and recovery zones reflect the spatial variability of oil removal rates in the mangrove forest. This study identifies the multitemporal analysis of aerial photographs as a useful tool for assessing a system's capacity for recovery and monitoring the long-term residual effects of pollutants on vegetation dynamics, thus giving support to mangrove forest management and conservation. |
Identificador |
Braz. j. oceanogr.,v.60,n.2,p.159-170,2012 1679-8759 http://www.producao.usp.br/handle/BDPI/40240 10.1590/S1679-87592012000200006 http://www.scielo.br/scielo.php?script=sci_pdf&pid=S1679-87592012000200006&lng=en&nrm=iso&tlng=en |
Idioma(s) |
eng |
Publicador |
Universidade de São Paulo, Instituto Oceanográfico |
Relação |
Brazilian Journal of Oceanography |
Direitos |
openAccess |
Palavras-Chave | #Coastal wetland #Remote sensing #Impact assessment #Monitoring #Coastal management #Zona úmida costeira #Sensoriamento remoto #Avaliação de impacto #Monitoramento #Gestão costeira |
Tipo |
article original article |