摘要
【目的】研究小兴安岭地区的森林火险与火发生规律,调查主要森林类型的可燃物特征,分析潜在火行为,为林火管理提供科学依据。【方法】根据1980—2010年地面气象观测数据,利用R计算火险天气指数,分析火险指数、火发生和过火面积的变化。采用标准地方法调查小兴安岭6种典型林分的可燃物特征,利用可燃物特征分类系统模拟各可燃物类型在不同天气情景下的潜在地表火和树冠火行为特征。【结果】小兴安岭的林火主要发生在春季(4—6月)和秋季(9—10月)2个时段,干旱年份夏季也可能发生森林火灾。森林的地表可燃物积累较多,主要为地表凋落物和木质可燃物(<1000 h),地表火强度随可燃物含水率降低而增大。林下植被以绣线菊(Spiraea salicifolia)-铁线蕨(Adiantum capillus-veneris)为主的林分潜在地表火蔓延速度显著高于林下以暴马丁香(Syringa reticulata subsp.amurensis)-苔草(Carex sp.)为主的林分,但其火强度低于林下以暴马丁香-苔草为主的林分。针叶林和针阔混交林都可能发生树冠火。【结论】林火管理有效减少了火发生。小兴安岭北部林区可燃物载量多,潜在火行为相关指数高,是未来林火管理的重点区域。干旱情景下,6种林分类型均有发生树冠火的可能,可以通过清理可燃物梯和减小针叶树种的密度来降低森林火灾风险。
【Objective】The aim of this study was to describe fire weather and fire regime.We investigated fuel characteristics and analyzed fire potentials in Xiaoxing’an Mountains,which would be valuable for improving the fire management in this region.【Method】Fire weather index(FWI)was calculated on R platform with the observed climate data from 1980 to 2010.We presented the temporal and spatial variation of FWI,fire occurrence,and postfire burned areas.Sampling plots(20 m×20 m)were set up in six primary forest types for fuel investigation during the fire season of 2020.The Fuel Characteristic Classification System(FCCS)was employed to simulate potential surface and crown fires for each forest type under multiple weather scenarios.【Result】The results showed that fires mainly occurred in spring(from April to June)and autumn(September and October),but appeared somewhat in dry summers.Surface fuels were accumulated significantly,which included wood fuel(<1000 h time lag)and litters.Surface fire intensity increased with the decreasing fuel moisture content.Forests with understory vegetation of Spiraea salicifolia and Adiantum capillus-veneris showed the lower fire intensity and faster potential surface fire spreading than those forests with Syringa reticulata subsp.amurensis and Carex sp.Crown fires occurred in both the coniferous forests and coniferous and broad-leaved mixed.【Conclusion】Fire management has effectively reduced forest fire potentials in Xiaoxing’an Mountains.The northern subregion was the critical area of forest fire management in the future due to high fuel loadings and fire potentials.All forest types had displayed the probability of crown fire under the drought scenarios.We inferred that the fire risk could be reduced by clearing the fuel ladder and reducing the density of coniferous trees.
作者
田晓瑞
宗学政
王志成
刘嘉雷
TIAN Xiaorui;ZONG Xuezheng;WANG Zhicheng;LIU Jialei(Key Laboratory of Forest Protection of National Forestry and Grassland Administration,Institute of Forest Ecology,Environment and Nature Conservation,Chinese Academy of Forestry,Beijing 100091,China;Emergency Rescue and Support Center of Hei-longjiang Province,Harbin 150000,China)
出处
《陆地生态系统与保护学报》
2021年第1期47-58,共12页
Terrestrial Ecosystem and Conservation
基金
国家自然科学基金资助项目(31770695)
中国林业科学研究院基本科研业务费专项(CAFYBB2019ZB003)。
关键词
火动态
可燃物特征
火行为
小兴安岭
fire regime
fuel characteristics
fire behavior
Xiaoxing'an Mountains
