New insight into global blue carbon estimation under human activity in land-sea interaction area: A case study of China

The C sequestration in coastal blue carbon (C-b) ecosystems, including mangroves, seagrasses and saltmarshes, was discovered to be useful in mitigating the increasing trend of carbon dioxide (CO2) emission due to climate change. In this study, we systematically estimate traditional C-b ecosystem distribution and the associated C-b sequestration rate, and then further quantify the C-b sinks fishery contribution to C-b ecosystem due to human activity in coastal ecosystem. The results show that the global C-b ecosystem is able to store 10.8 PgC, wherein biomass and soil are able to store 2.13 and 8.68 PgC, respectively. In China, the C-b pools are 162 TgC in mangroves, 67 TgC in saltmarshes and 75 TgC in seagrass. The human activity induced global C-b sink fishery on C-b ecosystem is about 26.58-37.6 TgC yr(-1), accounting for 30.7%-43.4% of the world's traditional C-b sequestration ecosystem. The global C-b sequestration potential reaches up to 86.59 Tg yr(-1), while China can explain 1.70% of the world's total C-b sequestration. However, in China, the C-b sequestration due to human activity reaches up to 632-7.89 TgC yr(-1), accounting for 20.9%-23.7% of global C-b sink fishery. Therefore, it is very important to build the C-b sink fisheries measure and monitor system to scientifically valuate C-b sink fisheries and associated development potential. (C) 2016 Elsevier B.V. All rights reserved.