Abstract:

The state-owned forest regions are the key regions to implement carbon neutralization in China. Accurate estimations of carbon storage and carbon sequestration potential of forest vegetation are of great significance for making strategies to cope with climate change and for coordinating regional eco-economy-social development. Based on the data of forest resource survey type II, the carbon storage and density of forest vegetation in the key state-owned forest region of Daxing’ anling, Heilongjiang Province were estimated by using the volume-biomass method on the basis of tree species (groups) and age groups. Based on the space-time substitution method, the carbon sequestration potential of forest vegetation was evaluated according to the ecological regionalization of forest vegetation and the type of zonality climax community. The results showed that (1) the total carbon storage and average carbon density of forest vegetation were 2.7246×10⁸ Mg and 39.46 Mg∙hm^-2, respectively. The proportion of carbon storage in arbor forest was 99.93%, and its average carbon density was 4.00 times of that in shrub wood and 3.72 times of that in open forest. (2) The carbon storage and carbon density of forest vegetation varied greatly in different regions. The regions of Xinlin Forestry Bureau (3.4497×10⁷ Mg) and Panzhong National Nature Reserve (1.0936×10⁶ Mg) had the highest and lowest carbon storage, respectively. The regions with the highest and lowest carbon densities were Shuanghe National Nature Reserve (59.68 Mg∙hm^-2) and Pan National Nature Reserve (22.11 Mg∙hm^-2). The establishment of nature reserves and reasonable and ordered human intervention both played positive roles in improving the carbon sequestration capacity of forest vegetation. (3) The proportion of carbon storage in Larix gmelini forest was nearly half of the total carbon storage in the research area, and the average carbon density of Pinus sylvestris var. mongolica forest was much higher than that of other forest types. (4) In general, forests for timber and for seed production had the largest carbon storage and average carbon density. (5) The half-mature forest is the age group with the largest carbon storage, and the average carbon density rose with the increase of age. (6) The carbon sequestration potential in total was 1.9367×10⁸ Mg, mainly owing to the growth of existing forest vegetation. To sum up, it is recommended to strengthen the theoretical research and technological research on the protection and restoration of natural secondary forests, to improve the quality and stability of forest ecosystems, to enhance their capacity to sequester carbon and increase sink, and to innovate the management of forest vegetation carbon sink, as well as to broaden the value realization path of ecological products in the forest carbon sink.

Key words: forest carbon storage, carbon density, carbon sequestration potential, volume-biomass method, state-owned forest region

摘要：

国有林区是中国实施碳中和行动的重要区域,准确估算其森林植被碳储量及固碳潜力,对于指导制定应对气候变化策略,统筹区域生态-经济-社会协调发展具有重要意义。以黑龙江大兴安岭重点国有林区为研究对象,基于森林资源二类调查数据,在分树种（组）且分龄组的基础上,采用材积源生物量法对其森林植被碳储量和碳密度进行了测算。运用空间代替时间法,并结合林区植被生态区划情况和地带性顶级群落类型,对林区森林植被固碳潜力进行了评估。结果表明,（1）黑龙江大兴安岭重点国有林区森林植被总碳储量为2.7246×10⁸ Mg,平均碳密度为39.46 Mg∙hm^-2。乔木林碳储量占比高达99.93%,其平均碳密度是灌木林的4.00倍、疏林的3.72倍。（2）不同区域森林植被碳储量和碳密度差异悬殊,碳储量最多和最少的区域分别是新林林业局（3.4497×10⁷ Mg）和盘中自然保护区（1.0936×10⁶ Mg）,碳密度最大和最小的区域分别是双河自然保护区（59.68 Mg∙hm^-2）和盘中自然保护区（22.11 Mg∙hm^-2）;自然保护区的设立和合理有序的人为干预对于提升森林植被固碳能力具有一定的积极作用。（3）落叶松林（Larix gmelinii）碳储量占比接近林区总碳储量的1/2,樟子松林（Pinus sylvestris var. mongolica）平均碳密度远高于其他森林类型。（4）碳储量最多和平均碳密度最大的林种分别是一般用材林和母树林。（5）中龄林是碳储量最多的龄组,平均碳密度随龄组的增加而增大。（6）林区总固碳潜力为1.9367×10⁸ Mg,主体贡献源于现存森林植被的生长。建议加强天然次生林保护与修复的理论研究和技术研发,提高森林生态系统质量和稳定性,增强其固碳增汇能力。创新森林植被固碳增汇管理,拓展林业碳汇生态产品价值实现路径。

关键词: 森林碳储量, 碳密度, 固碳潜力, 材积源生物量法, 国有林区