Mangrove carbon budgets suggest the estimation of net production and carbon burial by quantifying litterfall

Abstract

Soil carbon burial is the major process enabling mangroves to function as carbon sinks. However, the amount of deposited materials derived from allochthonous or autochthonous inputs in the soil carbon pool of mangroves remains uncertain. Mangrove-derived carbon burial is often laboriously estimated by monitoring the production and decomposition. In this study, ten carbon budgets covering different habitat features were constructed in situ for two mangrove species (Kandelia obovata and Avicennia marina) with distinct root structures. The mangrove-derived carbon burial rate was 0.25–1.55 Mg C ha−1 yr−1 for K. obovata and 0.36–1.00 Mg C ha−1 yr−1 for A. marina. Combined with other studies, there were positive and linear correlations between the carbon burial rate and litterfall production for the two mangroves, which suggests that the carbon burial rate for K. obovata and A. marina can be estimated using 14.8 % and 10.9 % of the litterfall production rate, respectively. The results of dbRDA with DistLM models further showed that wind speed and precipitation were the main factors affecting carbon burial in K. obovata and A. marina mangroves.