Monitoring mangrove degradation caused by oil spills using spaceborne multispectral and SAR imagery

Area of Science:

• Ecology
• Remote Sensing
• Environmental Science

Background:

• Mangroves are vital coastal ecosystems threatened by disturbances like oil spills.
• Effective monitoring of mangrove health post-oil spill is crucial for conservation.
• Scalable solutions are needed to assess oil spill impacts and cleanup efficacy.

Purpose of the Study:

• To evaluate combined spaceborne multispectral and SAR imagery for monitoring oil spill impacts on mangroves.
• To assess the effectiveness of oil spill cleanup efforts using remote sensing data.
• To map mangrove species distribution and their response to oil contamination.

Main Methods:

• Utilized spaceborne multispectral and Synthetic Aperture Radar (SAR) imagery.
• Developed an approach combining optical vegetation indices and SAR data.
• Mapped dominant mangrove species and their health indicators.
• Tested the methodology in historical spill sites (Bertioga channel, Barataria Bay) and the 2019 Brazil spill area.

Main Results:

• Successfully detected changes in mangrove health and species distribution post-oil spill.
• Tracked symptoms of plant stress, such as defoliation, in historically affected areas.
• Found no or minor alterations in mangrove health in northeastern Brazil four years after the 2019 oil spill.

Conclusions:

• Combined optical and SAR imagery is a capable tool for assessing oil spill impacts and cleanup success in mangroves.
• Favorable meteorological and coastal conditions, alongside cleanup efforts, likely mitigated severe impacts of the 2019 Brazil oil spill.
• The study provides a scalable remote sensing approach for future mangrove oil spill monitoring.