不同演替阶段马尾松林地表可燃物负荷量及其影响因子

目的 分析马尾松林不同演替阶段负荷量的变化特征，确定影响地表可燃物负荷量的关键因子。 方法 以武夷山国家公园中不同龄级马尾松纯林为研究对象，采用空间替代时间方法，分析马尾松林演替发展中不同类型地表可燃物的负荷量特征及其与地形、林分、气象等影响因子的关系。 结果 显示：（1）随着马尾松林的演替，地表活可燃物负荷量呈递减趋势，地表死可燃物和地表总可燃物负荷量则呈递增趋势；且总可燃物负荷量主要是由于1 h时滞细小可燃物的负荷量构成。（2）演替初期形成的马尾松幼龄林和后期的成熟林差异最为明显，至演替后期活地表可燃物下降了47.21%；死地表可燃物增加了113%。（3）RDA排序结果表明地形因子中的海拔、坡位，林分因子中的平均枝下高、平均胸径、郁闭度及气象因子中的空气温度与地表可燃物负荷量关系密切。（4）线性回归分析发现影响不同类型地表可燃物的环境因子不尽相同；平均胸径对灌木负荷量影响最大；坡位对草本、1 h时滞负荷量影响最大；平均枝下高对10 h时滞和总可燃物负荷量影响最大。 结论 不同演替阶段的马尾松林地表可燃物的负荷量不同，不同类型地表可燃物的影响因子不同。

Surface Fuel Loading of Pinus massoniana Forest in Different Succession Stages and Relevant Affecting Factors

Objective Based on the analysis of the variation characteristics of the fuel loading of Pinus massoniana forest in different succession stages, to determine the key factors affecting the surface fuel load. Method Taking pure P. massoniana forests with different age classes in Wuyishan National Park as the research object, alternative method of temporal and spatial was used to analyze the characteristics of different types of surface fuel loading and their relationship with terrain, stand, and meteorological factors. Result (1) With the succession of P. massoniana forest, the surface live fuel loading decreased, while the dead fuel loading and total fuel loading increased. The total fuel loading was mainly caused by 1 hour dead fuel loading. (2) The difference between young and mature P. massoniana stands was the most obvious. At the late stage of succession, the surface live fuel loading decreased by 47.21% and the surface dead fuel loading increased by 113%. (3) According to RDA ranking method, the surface fuel loading were closely related to terrain factors (such as altitude, slope position), stand factor (such as average branch-free bole height, average DBH, and canopy density) and meteorological factors (such as air temperature). (4) Linear regression analysis showed that different types of surface fuel loading had different influence factors, among which the average DBH had the greatest impact on the shrub fuel loading, the slope position had the greatest impact on the herb fuel and 1 hour dead fuel loading, the average clear bole height had the greatest impact on the 10 hour dead fuel and total fuel loading. Conclusion Surface fuel loading of P. massoniana forest are different in various succession stages and the influence factors vary with different types of surface fuel.