长株潭城市群生态绿心地区森林生态系统碳储量评估分析

Assessment and Analysis of Forest Ecosysytem Carbon Reserves in Ecological Green Core Area of Greater Changsha Metropolitan Region

利用野外实测数据和异速生长生物量方程,结合In VEST模型表征各层空间分布,对长株潭(长沙-株洲-湘潭)城市群生态绿心区森林生态系统碳储进行了定量评估。结果表明,长株潭城市群生态绿心地区2022年森林生态系统平均总碳密度为170.75 Mg/hm^(2),其中,乔木层、灌木层、草本层、凋落物层和土壤层平均碳密度分别为81.62、3.92、0.27、3.12 Mg/hm^(2)和81.82 Mg/hm^(2)。植被层是区域碳密度的主要贡献者,约占总密度的50.25%。区域植被类型碳密度表现为阔叶树种低于针叶树种,纯林低于混交林。长株潭城市群生态绿心地区2022年森林生态系统总碳储量为3 836.17Gg,乔木层、灌木层、草本层、凋落物层和土壤层碳储量分别为1 833.63、88.15、6.10、70.07 Gg和1 838.22 Gg。植被层与土壤层是区域森林生态系统的主要碳库,约占碳储总量的98.17%。采用In VEST模型表征区域分布,长株潭城市群生态绿心地区碳储分布在空间上表现为东部、湘江东岸地区水平较高,西部、西北地区水平较低,与森林资源分布格局具有良好的一致性。至2022年,生态绿心区森林生态系统碳储良好,是湖南省平均水平的1.3倍。研究结果可在探明区域碳汇现状的同时,为区域高质量发展及双碳目标的实现提供决策依据。

Based on the field data and allometric biomass model,combined with InVEST model to characterize the spatital distribution of each layer,the forest ecosystem in the ecological green core area of Greater Changsha(Changsha-Zhuzhou-Xiangtan)Metropolitan Region was quantitatively evaluated in this paper from the perspective of ecology.The average total carbon density of forest ecosystem in the ecological green core area of the region in 2022 was 170.75 Mg/hm^(2),in which the values of the average carbon density of tree layer,shrub layer,herb layer,litter layer,and soil layer were 81.62,3.92,0.27,3.12,and 81.82 Mg/hm^(2),respectively.Vegetation layer played a key role in the regional carbon density by occupying about 50.25%of the total value.The carbon density of broadleaf species was lower than that of conifer species,and that of pure forest was lower than that of mixed forest.The total carbon reserves of forest ecosystem in the region in 2022 were 3836.17 Gg,and the carbon reserves of tree layer,shrub layer,herb layer,litter layer and soil layer were 1833.63,88.15,6.10,70.07,and 1838.22 Gg,respectively.Vegetation layer and soil layer,as the main carbon pools of regional vegetation types were similar to each other.InVEST model was used to represent the regional distribution.In terms of spatial distribution,the carbon reserves in the ecological green core of the region were higher in the east and the eastern bank of the Xiangjiang River,and lower in the west and northwest,which was highly in consistency with the distribution pattern of forest resources.As of 2022,the forest ecosystem carbon storage in the region was in good condition,1.3 times that of the average level in Hunan Province.The research results can not only provide the background data of regional carbon sink status,but also provide the decision-making basis for regional high-quality development and the realization of dual carbon goals.