Blue carbon sequestered in the mangrove forests of Govatr Bay; Iranian coasts of the Oman Sea

Mangroves are the most efficient coastal environments for carbon sequestration, which can play an effective role in modification of increasing greenhouse gases. In this study, for the first time, the carbon storage in soils and mangrove trees in mangrove forest of Govatr Bay were evaluated. The amount of sediment carbon in sediment cores was determined as well as the diameter on breast height and height of trees were measured in 12 stations in Bahu and Govatr Estuaries. Satellite imagery showed that the total area of the Govatr Bay mangrove forest is 450 ha, 67% of which is high density forest. The amount of soil carbon in the region fluctuates between 1.9 to 3.8%, which is in the range of the global average (2.2%). The average carbon content of the top 1m of Govatr Bay is 393 tons per hectare (t ha-1), which is 30% higher than the global average. The total amount of carbon in top 1m of Govatr mangrove soil was estimated at 177,000 tons, 70% of which is sequestered in Bahu Estuary mangroves. The total amount of soil carbon in Govatr and Bahu Estuaries is 121600 and 210500 tons, respectively. A total of 64,100 tons of carbon is stored in the mangrove trees of Govatr Bay, 64% of which are related to the Bahu Estuary. A total of 376,000 tonnes of carbon (equivalent to 1,378,000 tonnes of carbon dioxide) has been stabilized in the Govatr forest, only 11% of which is stored in trees. Estimates show that if the Govatr are completely deforested, more than 279,000 tons of carbon dioxide will re-mineralize into the atmosphere.