Effect of hydrological restoration on the productivity of subterranean roots in the mangroves of Laguna de Terminos, Mexico

Background: Changes in hydrological patterns produce degradation that affects forest structure and primary productivity. With actions of hydrological restoration, it is intended to restore biogeochemical conditions to facilitate the establishment, survival and growth of mangrove vegetation to recovering the forest structure and the productivity of underground roots (< 20 mm). Research question: Inducing changes in environmental variables through hydrological restoration reactivate the process of roots production? Study species: Biomass and fine roots production of Avicennia germinans were used as indicators of restoration success. Study sites and dates: This study was carried out from August 2013 to February 2015 in Isla del Carmen, located in Terminos Lagoon, Campeche. Methods: The study included four sampling sites, three of which were sites restored at different times. The fourth one was a natural undisturbed mangrove patch used as a reference for comparisons. After incubation of about 18 months within buried growth cores in each study site, biomass and roots production were quantified and contrasted. Results: The restored sites showed a lower root production (< 20 mm) (17 to 233 g m(2) yr(-1)) regard to the reference site (414 g m(2) yr(-1)). The analyses showed that production is determined by the forestry structure and hydrological conditions. Conclusion: The proportion of roots > 2 mm in diameter was greater in the reference site and decreased towards the restored sites, indicating that the forest structure (natural regeneration) and the time (years) after the restoration was important for the functional recovery of the mangrove ecosystem.