Geovisualizing land degradation risk in Southeast Brazil Using remote sensing and GIS-based assessment

Area of Science:

• Environmental Science
• Geospatial Analysis
• Sustainable Development

Background:

• Land degradation threatens ecosystem services and sustainable development, particularly in areas with rapid land-use change.
• Coastal regions face unique challenges due to their ecological and socio-economic importance.
• Understanding land degradation dynamics is crucial for effective conservation and policy development.

Purpose of the Study:

• To assess and visualize land degradation risk in Rio de Janeiro State, Brazil, using an integrated geospatial approach.
• To identify conservation hotspots and inform decision-making for land management.
• To validate the UNEP-PAP/RAC framework in a humid tropical coastal environment.

Main Methods:

• Integrated geospatial approach combining remote sensing, GIS, and spatial multi-criteria analysis.
• Application of the UNEP-PAP/RAC framework to satellite imagery for land classification.
• Development of a geospatial prioritization model incorporating biophysical and socio-economic variables.

Main Results:

• 68.4% of the landscape is stable, while 7.8% is unstable, primarily due to sheet erosion at agricultural frontiers.
• 51.7% of the area is classified as Stable Medium Priority, indicating latent vulnerability.
• 4.6% of the area is Unstable High Priority, requiring immediate intervention.
• Significant land-use changes observed: 199% urban expansion and 34% decline in agricultural mosaics.

Conclusions:

• The UNEP-PAP/RAC framework is effective for assessing land degradation in humid tropical coastal zones.
• Actionable geovisualization outputs and a spatial decision-support tool were developed for targeted land management.
• Findings contribute to soil conservation and sustainable development policies in Brazil, highlighting anthropogenic drivers of degradation.