Pars Special Economic Energy Zone (PSEEZ) in the north of the Persian Gulf has made major changes to the landscape of
the Nayband mangrove forest in Iran, but there have been very few studies on the carbon in mangrove forests of the region. To study the carbon stock of the mangrove forests in Bushehr, and to compare it according to the distance from PSEEZ, some mangrove forests, including 6 stations in Asalouyeh, 2 stations in Basatin (close to PSEEZ), and 1 station in Malegonzeh (far from the PSEEZ) were sampled in November 2018. The carbon of trees was calculated by allometry equations and the carbon of sediment was measured by the Walkley and Black method. The results showed a signifcant diference between the forests in biomass, carbon of vegetation, and sediments (P< 0.05). The carbon stock of the mangrove vegetation was 34.92, 12.50, and 27.54 t ha−1 in Asalouyeh, Basatin, and Malegonzeh forests, respectively, while the carbon stock of sediments was 867.4, 728.4, and 612.6 t ha−1 in the mentioned forest, respectively. The highest total carbon was observed in the Asalouyeh and the lowest was observed in the Malegonzeh. The pattern of carbon was diferent in the sediment depth profle in the three forests. The rate of the carbon storage was 6.6 t ha−1 y−1 and 3.33 t ha−1 y−1 in Asalouyeh and Basatin, respectively. The carbon and CO2 sequestration rate in Basatin was lower than Asalouyeh. According to the results, mangrove forests in the area can act as a carbon sequestration service against the CO2 emitted by PSEEZ, if their habitats are not destroyed. The rate of the CO 2 sequestration was 22.46 t ha−1 y−1 in Nayband forest. The carbon stock was 640.14–902.32 t ha−1, which was equal to and greater than the carbon stock of the other mangroves in the world
