陇南市主要林型可燃物载量与环境因子的关系  

Relationship between the fuel load and environmental factors of the main forest types in Longnan City

作　　者：王康锋 罗永忠[1] WANG Kangfeng;LUO Yongzhong(College of Forestry,Gansu Agricultural University,Lanzhou,Gansu 730070,China)

机构地区：[1]甘肃农业大学林学院,甘肃兰州730070

出　　处：《森林与环境学报》2023年第6期651-658,共8页Journal of Forest and Environment

基　　金：甘肃省生态资源监测中心省级林业草原资源保护与发展基金·林业和草原火灾风险普查(701-03723041)。

摘　　要：为探究陇南市主要森林类型可燃物载量与环境因子的关系,采用样地调查方法,对陇南市4种主要森林类型林下可燃物(灌木、草本、枯枝落叶和腐殖质)载量特征进行分析,并对影响可燃物载量的9个环境因子(海拔、坡度、坡向、坡位、郁闭度、林分密度、平均树高、平均胸径和龄组)进行冗余分析(RDA),建立可燃物载量预测模型。结果表明:油松、落叶松、华山松、栎类林下可燃物总载量分别为18.85、16.54、10.74、8.12 t·hm^(-2);在4种森林类型林下可燃物载量中,腐殖质与1 h时滞可燃物载量占比最高,其中,落叶松1 h时滞可燃物载量占其总可燃物载量的50%,油松腐殖质载量占其总可燃物载量的46%,且落叶松1 h时滞可燃物载量与栎类、华山松1 h时滞可燃物载量存在显著差异(P<0.05),油松腐殖质载量与其他3种森林类型腐殖质载量存在显著差异(P<0.05)。RDA结果表明,平均树高、林分密度和坡向是影响林下可燃物载量的主要因子;逐步回归法建立林下可燃物载量预测模型,其中落叶松林下可燃物载量模型精度最高,R^(2)=0.88;油松林下可燃物载量模型精度最低,R^(2)=0.64;栎类和华山松林下可燃物载量模型中R^(2)分别为0.69、0.77。This study aims to investigate the relationship between combustible load and environmental factors in Longnan City.We conducted an analysis of combustible load characteristics,including shrubs,herbs,litter,and humus,within four primary forest types in Longnan City using a sample plot survey.Additionally,we redundantly analyzed nine environmental factors(altitude,slope,aspect,slope position,canopy density,stand density,average tree height,average DBH,and age group)that influence combustible load.The results revealed the total combustible loads of Pinus tabulaeformis,Larix gmelinii,Pinus armandii,and Quercus to be 18.85,16.54,10.74 t·hm^(-2),and 8.12 t·hm^(-2),respectively.Among these forest types,the highest load was observed for humus and 1-hour delayed combustible materials.Larix gmelinii accounted for 50% of the total 1-hour delayed combustible materials load,while Pinus tabulaeformis contributed 46% of the total humus load,which is significantly different between Larix gmelinii 1-hour delayed fuel load and the Quercus,Pinus armandii 1-hour delayed fuel load(P<0.05),and the difference between Pinus tabulaeformis humus load and the other three forest types was significant(P<0.05).The redundancy analysis results indicated that average tree height,stand density,and slope direction(P<0.05)were the main factors affecting combustible load within the forests.We established a prediction model for combustible load within forests using stepwise regression.The accuracy of this model was highest for Larix gmelinii(R^(2)=0.88)and lowest for Pinus tabulaeformis forest(R^(2)=0.64).The R^(2) values for the fuel loading models of Quercus and Pinus armandii forests were 0.69 and 0.77,respectively.

关 键 词：可燃物载量 冗余分析 环境因子 可燃物模型 

分 类 号：S762.1[农业科学—森林保护学]