Abstract:According to the latest definition of “Carbon Sink Fisheries”, fishing is one of the three basic modes of fisheries carbon sink and carbon sink amplification. In this study, the total carbon sink and net carbon sink for capture stock in China´s coastal ocean from 1979 to 2020 were assessed by the carbon content assessment method. For determining the total carbon sink for capture stock, carbon removal was first assessed by the carbon content of capture stock and fishing yield, and subsequently, the carbon content of phytoplankton was assessed at the end according to the food web mechanism and ecological conversion efficiency of each trophic level. The net carbon sink is the sum of carbon removal and carbon storage and can be calculated as the proportion of the total carbon sink. With the development and management of the marine fishery, carbon sink for capture stock in China´s coastal ocean has changed significantly over the past 40 years. The total carbon sink increased rapidly from 1458×104 t in 1979 to 6330×104 t in 1999 and then decreased to 4983×104 t in 2020. The average total carbon sink for the last three years (2018–2020) was 5246×104 t, equivalent to 701×104 ha of compulsory afforestation per year and about 8 times the total carbon sink for shellfish and macroalgae mariculture. The net carbon sink increased rapidly from 511×104 t in 1979 to 2215×104 t in 1999 and then decreased to 1744×104 t in 2020. The average net carbon sink for the last three years (2018–2020) was 1836×104 t, equivalent to 246×104 ha of compulsory afforestation per year and about 4 times of net carbon sink for shellfish and macroalgae mariculture. The study also proposed relevant suggestions for improving the accuracy of carbon sink assessment for capture stock and for enhancing carbon sink amplification.
