重大森林恢复计划下的碳增汇效应——基于石柱县两次森林资源二类清查的分析

Estimatingcarbon sequestrationof the major forest recovery plan: based on the analysis of forest inventory data of Shizhu County

利用两次森林资源二类调查数据和林业工程数据,运用换算因子连续函数法,基于林分(小班)尺度测定森林含碳量,估算2002—2012年的10年间样区恢复计划实现的碳增汇贡献。结果表明:(1)近10年样区森林资源碳贮量和碳密度均获得较大程度的增加,碳贮量增加1.00TgC,平均碳密度增加2.13MgC/hm2;(2)森林碳贮量和碳密度的增加因重大森林恢复计划实施的非均衡性在空间上呈现显著差异,尤其方斗-七曜所夹槽谷区和七曜山南部中山区增幅较快;(3)关键林分因子,碳增汇能力最强的是松、杉、柏及针阔混,累计达1.36TgC,且主要集中于中、幼龄林阶段,累计碳增量0.94TgC;(4)近10年样区重大森林恢复计划共实现碳增汇0.97TgC,占同期森林碳增量的97.66%;平均碳密度增量7.64MgC/hm2,明显高于恢复计划未覆盖范围的森林碳密度增加值,尤其是天然林保护工程碳增量最大,占恢复计划实现碳增汇总量的85.57%;(5)更为重要的,因碳增汇主要发生在中、幼龄林阶段,在中、幼龄林向近、成熟林演化过程中,伴随森林碳密度的增加,仍会展现出较大的碳增汇潜力;(6)研究有助于丰富人们对现已开展的重大森林恢复计划成效的理解和认识,为未来应对和减缓气候变化适应性对策的制定提供科学依据。

Since the late 1990s, the Chinese government has implemented six major forestry projects to increase forest carbon sequestration through afforestation, reforestation, and forest restoration. This paper estimatedthe amount of forest carbon sinks, using forest resource inventory data and forestry engineering data and conversion factors continuous function method. The amount of carbon sequestration of the last 10 years has been estimated to find out the major forest recovery plan＇s effect of carbon sinks. The results showed that：（ 1 ）In the past 10 years, carbon storage and density forest resources in sample have greatly increased. Carbonsequestration of forest has increased 1.00TgC and average carbon density of forest has increased 2.13MgC/hm^2. （2） There was a significant regional difference in the forest carbon sequestration and carbon density increases due to thenon-equilibriumof the major forest recovery plan. The increase of the forest carbon sequestrationand carbon density was occurred mainly in the valley between the Fangdou Mountain and Qiyao Mountain, because the Natural Forest Protection Project and the Grain for Green Projectcarried out more here. （3） Carbon sinks of pine, cedar, cypress and mixed coniferous increased as many as 1.36TgC. Carbon sinks of nearly mature forest and middle-aged forest and young forest increased more.Carbon sinks of middle-aged and young forest increased as many as 0.94TgC. Natural forest can save more carbon the plantation. （4） In the past 10 years, 97.66% carbon sequestration was caused by the major forest recovery plan. The average carbon density has increased 7.64MgC/hm^2 and it was higher than areas not covered by the major forest recovery plan. Carbon sequestration caused by the Natural Forest Protection Project was the most and it accounted for 85.57% of the total. Carbon sequestration caused by the Grain for Green Project was just 0.05TgC because of the late implementation time and bad effectiveness. （5） Carbonsequestration caused by the major forest recovery plan was mainly focus on middle-aged forest and young forest. Middle-aged forest and young forest have great potential to increase carbon sinks when they evolve into nearly mature forest and mature forest. （6） This study helps people to understand and recognize the effectiveness of the major forest recovery plan, and provides a scientific basis for developing policy to respond to and slow down global change.