甘肃太子山不同林型森林可燃物含水率与环境因子的关系

Characteristics of forest fuel water content in different forest types and its relationship with environmental factors in Taizi Mountain,Gansu Province

【目的】对甘肃省太子山国家级自然保护区不同林型下森林可燃物含水率进行系统研究,以期为该保护区森林可燃物的管理提供基础数据,同时为森林火险监测与火行为模拟研究提供参考。【方法】以研究区不同林型森林可燃物作为研究对象,对比分析森林可燃物含水率特征,并利用RDA排序法对其与环境因子的关系进行分析。【结果】乔木林地和灌木林地森林可燃物含水率分别为184.48%、177.76%,乔木林地森林可燃物含水率大于灌木林地;枯落物类型不同含水率也存在差异,其中灌木林地森林可燃物含水率无显著差异,乔木林地森林可燃物土壤腐殖质含水率最高(285.93%±162.40%),与其他枯落物存在显著差异。RDA排序揭示了该地区森林可燃物含水率与地形地貌、植被特征等9个环境因子的响应变量矩阵与解释变量矩阵之间多元多重线性回归的拟合值矩阵的PCA分析关系。不同林型森林可燃物含水率关键影响因子不同,其中海拔、郁闭度、林龄(P<0.05)是影响森林可燃物含水率的主要因子。【结论】不同林型森林可燃物含水率存在差异,枯落物类型不同含水率也存在差异;海拔、郁闭度和林龄是影响该地区森林可燃物含水率的主要环境因子。

【Objective】The forest fuel moisture content under different forest types in this area was systematically studied,in order to provide basic data for forest fuel management in this reserve,and provide reference for forest fire risk monitoring and fire behavior simulation.【Method】Taking forest fuels of different forest types in this area as the research object,the characteristics of forest fuel water content were compared and analyzed,and the relationship between forest fuel water content and environmental factors was analyzed by using RDA ranking method.【Result】The forest fuel moisture content of the tree forest was higher than that of the shrub forest,which was 184.48%and 177.76%respectively.There were also differences in the moisture content of litter types,among which the forest fuel moisture content of shrub forest had no significant difference,and the forest fuel soil humus moisture content of tree forest was the highest(285.93%±162.40%),which was significantly different from other litter types.The RDA ranking showed the PCA analysis relationship between the forest fuel moisture content,the response variable matrix and the explanatory variable matrix of 9 environmental factors such as landform,topography and vegetation characteristics.The main influencing factors of forest fuel moisture content were different in different forest types,among which elevation,canopy density and forest age(P<0.05)were the main influencing factors of forest fuel moisture content.【Conclusion】There are differences in the moisture content of fuel and litter in different forest types.The RDA ranking showed that elevation,canopy cover and forest age were the main environmental factors influencing the moisture content of forest fuels in this region.