The role of blue carbon in reversing mangrove degradation trends in Mexico

Blue carbon projects in Mexico, or the conservation and restoration of tidal wetlands such as mangroves, can reduce carbon emissions while providing additional ecosystem services for local communities. However, at the national scale, the “additionality” (or added project benefits) of mangrove projects is difficult to demonstrate due to recent slowing deforestation rates. While deforestation in Mexico decelerates, mangrove degradation is pervasive and spreading. Reversing or ending mangrove degradation could rapidly protect the carbon stored and reduce future greenhouse gas emissions. Here, we explore Mexico's conceptual, methodological, and social challenges for tackling mangrove degradation and achieving successful rehabilitation outcomes. We identified that the first challenge is establishing an accepted national definition of mangrove degradation compatible with earlier methods and measurable with spatial imaging techniques. Other challenges are aligning on-ground monitoring with remotely sensed degradation assessments, including reference sites, harmonizing national programs with global datasets, and standardizing information to meet blue carbon project accreditation requirements. Finally, knowledge sharing, collaboration, and reporting failed and successful projects are crucial for fast-forwarding reliable and verifiable blue carbon projects that effectively contribute to reversing mangrove degradation trends in Mexico. • Mangrove deforestation in Mexico is decreasing, although degradation is perversive and spreading. • Blue carbon projects addressing degradation could protect the carbon stored, and improve the well-being of coastal communities • Challenges to address degradation in Mexico include a lack of a national definition • Knowledge sharing and reporting of failed and successful carbon projects are crucial