Mangroves provide vital ecosystem services for livelihoods and sustainable development in tropical coastal communities, but they have been deforested in many nations. A common approach for restoring mangrove ecosystems in severely degraded areas or areas requiring rapid re-establishment is planting seedlings. Thousands of hectares of mangrove plantations have been established over the last several decades in Vietnam and Myanmar. Examination of mangrove plantation performance and factors influencing growth is important for developing management options for successful mangrove restoration. We surveyed 220 mangrove plantations in Vietnam and 216 in Myanmar. Growth data, environmental parameters, and management practice information were collected. We used boosted regression tree models to evaluate the most influential variables on plantation performance. Our results reveal that management and environmental factors play similar roles (35% vs 40%) in the success of Vietnam’s restoration plantations, while unplanned disturbances, e.g. illegal cutting, were the major threat (70%) to Myanmar’s plantation establishment. The results imply that silvicultural practices are less influential than mangrove protection on plantation success. Biomass growth of different mangrove species were modelled for forecasting carbon sequestration in both countries. Without major disturbances, most plantations had lower aboveground biomass growth rate than naturally regenerating stands (e.g. biomass of 8-year-old plantations was 39 Mg ha-1 while biomass of 9-year-old regenerating stands was 70 Mg ha-1 in Myanmar). At later successional stages (e.g. plantations older than 35 years), undisturbed plantations had similar biomass and species composition to adjacent mangroves that naturally regenerated (120 Mg ha-1 vs 135 Mg ha-1).
Audio/Video, Conference Presentation, SER2019
Society for Ecological Restoration