1988-2018年广西北海红树林蓝碳储量变化分析

Blue carbon stocks of mangrove from 1988 to 2018 in Beihai,Guangxi

蓝碳指储存在红树林、盐沼、海草床生态系统中的碳,约占所有生态系统碳储量的55%。本文基于1988-2018年广西北海的遥感图像,获取了时间间隔为五年的北海红树林面积变化数据,据此估算了蓝碳储量及碳库各主要组成部分的变化量。1988-2018年,北海红树林面积由459 ha增长至3320 ha,年度增长率为6.8%。该区红树林总面积保持增加趋势,1998-2003年,毁林挖塘行为导致面积减少150 ha。根据IPCC国家温室气体清单,计算了1988-2018年北海红树林总碳库量,红树林湿地无变化的区域碳储量稳定增加,由1988年的32064 t增长到2018年的214830 t,年度增长率为6.5%。采挖活动导致的土壤碳储量减少最多,其中,1998-2003年的损失量高达82392 t。本文首次计算了因人类活动导致的红树林蓝碳损失,并尝试进行了IPCC参数的地方化研究。该研究可为红树林生态系统修复以及蓝碳捕捉、转移、固定研究提供数据支撑,更好地服务于碳中和碳达峰国家战略。

Blue carbon refers to the carbon stored in mangrove,salt marsh and seagrass bed ecosystems occupying about 55%carbon stocks of all coastal wetlands.We analyzed mangrove changes in Beihai,Guangxi during 1988-2018 based on 5-year-period remote sensing images for mangrove blue carbon stock estimation.The mangrove area in Beihai increased from 459 ha to 3320 ha during 1988-2018,with an annual growth rate of 6.8%.Deforestation and pond digging had the greatest impact on some mangroves(dredging activities)with 150 ha loss between 1998 and 2003.The paper calculated the total carbon of mangroves in Beihai over the past 30 years based on IPCC guidelines for national greenhouse gas inventories.The carbon stock increased steadily from 32064 t in 1988 to 214830 t in 2018,with an annual growth rate of 6.5%.Excavation activities contributed much to carbon stocks decrease as the removal of soil carbon,with the largest loss of 80783 t between 1998 and 2003.The paper suggested that the local management should combine all stakeholders to strengthen mangrove conservation and restoration formulating more scientific,reasonable,efficient and practical policies and measures so as to better serve the national strategy of carbon neutral and peak carbon dioxide.