武夷山不同龄组和坡向马尾松次生林地表死可燃物热解特征  

Pyrolysis characteristics of surface dead fuel of Pinus massoniana forests with different age groups and slope aspects in Mount Wuyi

作　　者：李颖 余洪波[3] 胥清利 严思晓 周艳 张惠光 何东进[1,2,6] 游巍斌 LI Ying;YU Hongbo;XU Qingli;YAN Sixiao;ZHOU Yan;ZHANG Huiguang;HE Dongjin;YOU Weibin(College of Forestry,Fujian Agriculture and Forestry University,Fuzhou 350002,China;Research Centre of Southern Forest Resources and Environment Engineering Technology of Fujian Province,Fuzhou 350002,China;College of Life Science&Technology,Huazhong University of Science and Tech-nology,Wuhan 430074,China;Pushang National Forest Farm of Shunchang,Shunchang 353205,Fujian,China;Wuyishan National Park Scientific Research Monitoring Center,Wuyishan 354300,Fujian,China;Fujian Vocational College of Agriculture,Fuhzou 350119,China)

机构地区：[1]福建农林大学林学院,福州350002 [2]福建省南方森林资源与环境工程技术研究中心,福州350002 [3]华中科技大学生命科学与技术学院,武汉430074 [4]福建省顺昌埔上国有林场,福建顺昌353205 [5]武夷山国家公园科研监测中心,福建武夷山354300 [6]福建农业职业技术学院,福州350119

出　　处：《生态学杂志》2023年第6期1330-1338,共9页Chinese Journal of Ecology

基　　金：国家自然科学基金资助项目(41301203);福建农林大学林学学科创新团队项目经费(72202200205)资助。

摘　　要：马尾松是南方地区暖性针叶林的先锋树种,马尾松林是该区易燃森林群落类型之一。充分认识马尾松林地表可燃物的热解特征,对系统优化可燃物火行为模型和森林可燃物管理具有重要意义。以武夷山不同龄组马尾松林地表死可燃物为对象,运用热重分析方法,分析不同死可燃物类型(1小时时滞可燃物(1 h)和10小时时滞可燃物(10 h))的热解过程和热解参数;利用Coats⁃Redfern积分法对样品的快速热解阶段进行动力学分析,最终基于热解参数(着火温度、综纤维素的平均失重速率、综纤维素的分解时间和燃烧消耗的总质量)对可燃物燃烧性进行多维评价。结果表明:马尾松林不同龄组地表死可燃物的热解过程经历4个阶段,其中综纤维素分解阶段热解温度范围为170~371℃,失重量为50%~60%;木质素分解阶段热解温度范围为358~496℃,失重量为20%~40%。地表死可燃物综纤维素热解阶段活化能范围为50.03~61.83 kJ·mol^(-1),木质素阶段活化能为17.39~64.48 kJ·mol^(-1)。从龄组上看,1 h和10 h可燃物几乎都在马尾松幼龄林上易燃烧、持续性久和消耗量大,但燃烧不剧烈。从不同坡向上看,1 h可燃物在点燃性上评价结果较为一致,剧烈性、持续性和消耗性评价结果相差迥异;10 h可燃物的四维燃烧性则各不相同。四维燃烧性评价表明,马尾松林的地表死可燃物燃烧性在不同龄组和坡向上异质性特征明显。可见,在地表可燃物燃烧过程模拟或火行为模型构建中,应充分考虑坡向和树种年龄组等参数的异质性特征对结果精度的影响。Pinus massoniana is a pioneer species in the coniferous forest in southern China,which is one of the flammable forest community types.The knowledge on pyrolysis characteristics of surface fuels in Pinus massoniana forests is of great significance to improve fire behavior model and forest surface fuels management measures.Pyroly⁃sis processes and parameters of both 1⁃h dead fuel(1⁃h fuel)and 10⁃h dead fuel(10⁃h fuel)for different stand age groups of Pinus massoniana forest in Mount Wuyi were examined by the thermogravimetric analysis.The kinetic analysis of rapid pyrolysis stage was examined using Coats⁃Redfem integration method.A four⁃dimensional feature of their combustibility was evaluated based on four pyrolysis parameters(ignition temperature,average weight loss rate of healzocellulose,decomposition time of healzocellulose,and total mass consumed by combustion).The results showed four stages in the pyrolysis process of surface dead fuels in different stand age groups of Pinus massoniana forest.The pyrolysis temperature of holocellulose ranged from 170℃to 371℃,and the weight loss was 50%-60%.The pyrolysis temperature of lignin ranged from 358℃to 496℃,and the weight loss was 20%-40%.In the pyrolysis stage of dead surface fuels,the activation energy of holocellulose ranged from 50.03 kJ·mol^(-1) to 61.83 kJ·mol^(-1),and that of lignin ranged from 17.39 kJ·mol^(-1) to 64.48 kJ·mol^(-1).Across stand age groups,1⁃h fuel and 10⁃h fuel in young Pinus massoniana forest were the most ignitable,with lasting burning duration,high con⁃sumption but low intensity.In terms of shady slope and sunny slope,there was relatively consistent ignitability in the 1⁃h fuel,but quite different for the features of combustibility,sustainability and consumability.There was dif⁃ferent for four⁃dimensional flammability features for 10⁃h fuel.The results of four⁃dimensional flammability evalua⁃tion showed that the flammability of surface dead fuels in Pinus massoniana forest had distinct heterogene

关 键 词：热重分析 Coats⁃Redfem积分法 燃烧性 热解特性 武夷山国家公园 

分 类 号：S762[农业科学—森林保护学]