New Soil Health Index tracks Brazil's mangrove recovery in threatened coastal regions

Brazil's mangrove forests face growing threats from deforestation, urban expansion and climate change. Over 25,000 hectares have vanished since the 1970s in the Amazon's Maranhão and Pará regions alone. Now, a new tool is helping track recovery efforts in these critical ecosystems.

Scientists have developed a Soil Health Index (SHI) to measure mangrove soil vitality on a scale from 0 to 1. The index combines physical, chemical and biological data to assess how well restored areas function compared to healthy forests. When applied to the Cocó River estuary in Ceará, the SHI revealed gradual recovery in previously degraded sites.

The tool's flexibility allows it to adapt to different regions, incorporating local environmental conditions and priorities. Researchers plan to expand its use by mapping soil health nationwide and studying carbon storage in restored areas. Their goal is to refine the SHI further, ensuring it reflects real-world benefits like storm protection and fisheries support.

Brazil holds the world's second-largest mangrove coverage, with around 1.4 million hectares along its coast. Yet decades of human activity and climate pressures have weakened these ecosystems. The SHI offers a way to monitor restoration success and guide future conservation efforts.

The SHI provides a clear method for tracking mangrove recovery and prioritising conservation actions. By focusing on soil health, it helps ensure restored areas regain their role as climate buffers and coastal protectors. Further refinements could strengthen its use across Brazil's diverse mangrove regions.