Effect of mangrove reforestation on soil carbon accumulation

Abstract

The concern with the global carbon cycle, the emission of greenhouse gases (GHG), and their impacts on the global climate led researchers and public agencies to search for policies aimed at mitigating the increase in the concentration of GHG in the atmosphere. Mangroves represent the Terrestrian ecosystem which has more atmospheric C in their sinks, mainly in their soils. On the other hand, mangroves present the highest degradation rates, with 75% lost original areas. This study aimed to evaluate the temporal effect of reforestation in degraded mangroves on the restoration of soil carbon content. In the Environmental Preservation Area of Guapi-mirim (Rio de Janeiro - Brazil), five mangrove sectors under different replanting stages were identified (non-vegetated area - V, areas replanted in 2011, 2013, and 2015, as well as an area with vegetation over 30 years old, considered with stable). In these sectors, soil physical-chemical parameters (Eh, pH), particle size, and total organic C were evaluated. The results indicate significant changes both in the soil properties (pH, Eh) and in the organic C content, with an increase of 7,75 to 17,66% in the NV and reforested forests, respectively.