| 摘要: |
| 在全球碳中和与区域生态安全需求的背景下,洮河流域云杉人工林碳汇功能的优化日益关键。为探究碳储量分布特征及影响因素,该研究以洮河流域云杉人工林为对象,设置不同林龄(幼龄林、中龄林)与密度(925～2 800 trees·hm-2)样地,系统测定并综合评估乔木层不同器官(干、枝、叶、皮、根)、凋落物层以及土壤不同层次(0～10 cm、10～20 cm、20～40 cm、40～60 cm、60～80 cm)的碳储量及分布特征,深入分析林龄与密度对碳储量的影响机制。结果表明:(1)洮河流域云杉人工林生态系统总碳储量介于336.25～512.39 t·hm-2之间,整体呈现“土壤层 > 乔木层 > 凋落物层”的格局。(2)土壤层是生态系统最核心的稳定碳库,碳储量为256.89～300.45 t·hm-2,占总碳储量的69.90%,并且60%以上的土壤碳集中分布于0～40 cm土层。(3)乔木层碳储量为43.12～190.02 t·hm-2,表现出强烈的时空异质性,并且存在显著的“中龄林碳积累高峰”,碳在各器官中优先分配于干(22.46%～49.42%)和根(19.39%～29.35%),其分配策略受密度调控,高密度林分生物量向树干集中,中低密度林分各器官均衡增长,碳汇效率更高。(4)凋落物层的碳储量为12.53～21.92 t·hm-2,占总碳储量的3.58%～4.30%,但其碳含量高达306.04～389.32 g·kg-1,是连接地上与地下碳流通的关键枢纽。该研究证实,林龄与密度是驱动云杉人工林生态系统碳积累与分配的核心因子,实施以密度调控为核心的可持续经营策略,可有效挖掘该区域云杉人工林的碳汇潜力。该研究结果可为洮河流域人工林碳汇功能优化、生态系统保护及区域碳中和目标实现提供重要的理论依据与实践参考。 |
| 关键词: 林龄, 密度, 碳储量, 协同影响, 云杉林 |
| DOI：10.11931/guihaia.gxzw202511029 |
| 分类号:Q948 |
| 文章编号:1000-3142(2026)06-1046-10 |
| Fund project:甘肃省级生态文明建设重点研发专项-“黄河上游关键森林生态系统固碳潜力及提升技术研究”(25YFFA075); 甘肃省林草局自列项目-“甘肃省退耕还林生态林提质增效模式评估”(2024kj023); 甘肃省林业和草原局自列项目-“甘肃省公益林生态效益监测项目”(2021-89)。 |
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| Effects of stand age and density on carbon storage of Picea asperata plantations in the Taohe River basin |
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LING Lei1,2, REN Zengcao1,2, ZONG Wenzhen1, DING Aiqiang1,2, CHEN Zhengni1,2*
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1. Gansu Academy of Forestry, Lanzhou 730000, China;2. Gansu Xinglongshan Forest Ecosystem
Position Observation and Research Station, Yuzhong 730100, Gansu, China
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| Abstract: |
| In the context of global carbon neutrality and regional ecological security requirements, the optimization of the carbon sink function of Picea asperata plantations in the Taohe River basin has become increasingly crucial. To explore the distribution characteristics and influencing factors of its carbon storage, this study focused on P. asperata plantations within the Taohe River basin, establishing plots with varying stand ages(young and middle forests)and densities(925-2 800 trees·hm-2). It systematically measured and comprehensively evaluated the carbon storage and distribution characteristics of different organs(trunk, branch, leaf, bark, root)within the tree layer, the litter layer, and distinct soil horizons(0-10 cm, 10-20 cm, 20-40 cm, 40-60 cm, 60-80 cm). It provided an in-depth analysis of the mechanisms by which stand age and density influenced carbon storage. The results were as follows:(1)The total carbon storage of P. asperata plantation ecosystem in the Taohe River basin ranged between 336.25 to 512.39 t·hm-2. The overall pattern exhibited a hierarchy of carbon storage: soil layer > tree layer > litter layer.(2)The soil layer constituted the most fundamental stable carbon reservoir within ecosystems, holding carbon storage ranging from 256.89 to 300.45 t·hm-2. This accounted for 69.90% of total carbon storage, with over 60% of soil carbon concentrated within the 0-40 cm soil layer.(3)The carbon storage in the tree layer ranged between 43.12 to 190.02 t·hm-2, exhibiting pronounced spatio-temporal heterogeneity alongside a significant ‘mid-mature forest carbon accumulation peak'. Carbon was preferentially allocated to the trunk(22.46%-49.42%)and root(19.39%-29.35%)among the various organs. Its distribution strategy was density-regulated: biomass in high-density stands concentrated in the trunk, while in medium-to-low-density stands, all organs grew more evenly, resulting in higher carbon sequestration efficiency.(4)The carbon storage in the litter layer ranged from 12.53 to 21.92 t·hm-2, accounting for 3.58% to 4.30% of the total carbon storage. However, its carbon content was remarkably high at 306.04 to 389.32 g·kg-1, making it a pivotal hub connecting above-ground and below-ground carbon flows. This study confirms that stand age and density are the core factors driving carbon accumulation and distribution within P. asperata plantations ecosystems. By implementing sustainable management strategies centred on density regulation, the carbon sink potential of P. asperata plantations in this region can be effectively harnessed. The results provide crucial theoretical basis and practical guidance for optimizing the carbon sink function of plantations in the Taohe River basin, safeguarding ecosystem, and achieving regional carbon neutrality objectives. |
| Key words: stand age, density, carbon storage, synergistic effects, Picea asperata forests |
