Mangrove Restoration Calculator

Mangrove sequestration rates vary significantly by region and method, but typically range from 3 to 12 tonnes of CO₂ per hectare per year when combining above-ground biomass and soil carbon. Southeast Asian mangroves tend to have among the highest rates globally. This calculator applies regional averages derived from published literature including the Winrock International Global Removals Database.

Blue carbon refers to carbon captured and stored in coastal and marine ecosystems, including mangroves, saltmarshes, and seagrasses. Mangrove soils are exceptionally effective carbon sinks — their waterlogged, low-oxygen conditions slow decomposition, allowing organic carbon to accumulate for centuries. Soil carbon can account for 50–90% of total mangrove carbon storage, making it critical to include in any restoration estimate.

Yes — survival rate has a direct proportional impact on carbon sequestration. A project with 50% survival stores roughly half the carbon of one with 100% survival. The global average survival rate for mangrove restoration projects is estimated at 60–75%, though well-managed active planting programmes in suitable hydrological conditions can achieve above 85%.

Active planting involves nursery-raised seedlings planted directly by restoration teams, offering faster initial canopy closure and carbon uptake. Natural regeneration relies on existing seed sources and tidal hydrology to re-establish mangroves with minimal intervention — it is lower cost but slower to accumulate biomass. Hybrid approaches combine both, using planting to supplement naturally regenerating areas.

Mangrove growth and carbon accumulation rates depend on temperature, rainfall, tidal dynamics, species composition, and soil type — all of which vary geographically. Southeast Asian mangroves, for example, have high species diversity and fast growth rates in warm, humid conditions. East African and Pacific mangroves tend to grow more slowly. Regional coefficients in this calculator are based on peer-reviewed data from the scientific literature.

This calculator provides scientifically grounded estimates based on published regional averages, but it is not a substitute for a formal carbon accounting methodology such as Verra's VCS VM0033 (Methodology for Tidal Wetland and Seagrass Restoration) or Gold Standard protocols. For carbon credit certification, you will need site-specific measurements and third-party verification.

Young mangroves begin sequestering carbon from their first year, but rates accelerate significantly as the forest matures. Above-ground biomass accumulation is typically slow in years 1–5, then increases through years 6–20 as canopy closes and root networks expand. Soil carbon accumulation is more gradual but continues for decades. Most restoration projects see the largest cumulative gains between years 10 and 30.

Research published by Worthington & Spalding (2018) and the Global Mangrove Alliance estimates that approximately 8 million hectares of former mangrove habitat are potentially restorable worldwide, with Southeast Asia and Latin America holding the largest opportunities. However, successful restoration requires suitable hydrological conditions — restoring tidal flow is often more important than planting alone.