中国近海渔业生物捕捞群体碳汇评估

Carbon sink assessment for capture stock in China coastal ocean

中文关键词: 中国近海  捕捞群体  总碳汇  净碳汇  相关建议

英文关键词: China coastal ocean  Capture stock  Total carbon sink  Net carbon sink  Relevant suggestion

中文摘要:

      捕捞渔业生物群体的生产活动是发挥渔业碳汇功能和增汇的3种基本方式之一，其中，水生植物作为典型的碳汇生物，发挥至关重要的作用，据此，本研究采用碳含量法对1979―2020年中国近海渔业生物捕捞群体总碳汇和净碳汇进行了评估。总碳汇是通过捕捞产量和捕捞群体的碳含量估算捕捞群体的移出碳量，再根据食物网机制和各营养层级的生态转换效率，最终估算摄食的浮游植物碳含量；净碳汇是捕捞移出碳和储存碳之和，可根据占总碳汇的比例计算。随着海洋捕捞业的发展和管理的加强，40多年来，我国近海渔业生物捕捞群体碳汇有较大幅度的变化，本研究计算的总碳汇量从1979年的1458万t快速上升到1999年的6330万t，2020年下降至4983万t，其中，近3年(2018―2020年)平均每年为5246万t，约为近海贝藻养殖总碳汇的8倍；净碳汇量从1979年的511万t快速上升到1999年的2215万t，2020年下降至1744万t，其中，近3年(2018―2020年)平均每年为1836万t，约为近海贝藻养殖净碳汇的4倍。针对提高碳汇评估准确性和加强碳汇扩增，文末提出了相关建议。

英文摘要:

      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.