Greenhouse Gas Fluxes and Carbon Stock in Conserved and Degraded Mangroves

Mangrove degradation in tropical areas is an alarming phenomenon with significant local and global consequences for greenhouse gas (GHG) emissions and carbon storage (SCS).In this study, seasonal fluxes of carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) from soil and SCS were evaluated in mangroves with different ecological conditions (conserved and degraded) in the western coastal sector of Campeche, Mexico.The highest CO 2 fluxes (1108.5 to 1563.7mg m -2 h -1 ) were recorded during the dry season in the conserved mangroves.CH 4 fluxes were highest in the most degraded mangroves during the wet season (6071.4 to 6675.47µg m -2 h -1 ).N 2 O fluxes did not show significant differences between treatments (p>0.05), with the highest fluxes occurring during the rainy season in the Atasta mangrove forest (713.6 ± 258.1µg m -2 h -1 ).The highest contribution to global warming potential among seasons and sites was CO 2 (62.2 ± 34.1 Mg CO 2 -eq ha -1 yr -1 ), followed by N 2 O (15.7 ± 4.5 Mg CO 2 -eq ha -1 yr -1 ) and finally CH 4 with the lowest CO 2 -eq contribution of 9 ± 5.7 Mg CO 2 -eq ha -1 yr -1 .The conserved mangroves stored an average of 503.6 ± 96.7 Mg C ha -1 and the more degraded mangroves stored 275.1 ± 25 Mg C ha -1 .The results of the present study suggest that GHG emissions and SCS are strongly influenced by site ecological conditions, seasonality and variation in some soil properties so that the ecological degradation of mangroves can increase GHG emissions and reduce the ecosystem's capacity to store carbon.