摘要
【目的】建立森林火灾蔓延风险评估框架(包括发生危险、蔓延危险、蔓延风险3部分),基于GIS开展北京市延庆区多尺度(小班、村屯、乡镇)森林火灾蔓延风险评估,为延庆区林火管理提供依据,最大限度降低林火发生危险和林火蔓延造成的损失。【方法】基于延庆区2019年森林资源二类调查小班数据、森林可燃物数据、人口数据、30 m分辨率数字高程数据、气象数据,从野外火源管理难度和着火难易程度2个方面构建森林火灾发生危险评估指标体系,从森林可燃物、气象因子、地形因子、火行为4个方面构建森林火灾蔓延危险评估指标体系,应用层次分析法和熵权法相结合的主客观赋权法确定指标权重,利用加权综合评价法和面积加权平均法计算多尺度发生危险和蔓延危险指数,根据自然断点分级法划分等级。基于“危险性-暴露度-脆弱性”风险评估框架,从破坏森林资源和威胁生命安全2个方面评估森林火灾蔓延风险。【结果】1)野外火源管理难度的综合权重达到0.7713,是影响森林火灾发生危险的主要因素;火行为的综合权重达到0.4032,是影响森林火灾蔓延危险的主要因素。2)延庆区森林火灾发生危险从平原向山区逐步减小,高发生危险区域在小班、村屯、乡镇尺度上分别占比0.89%、0.52%、7.48%,主要分布在城区周围的平原区域;蔓延危险从平原向山区逐步增大,高蔓延危险区域在小班、村屯、乡镇尺度上分别占比46.19%、58.73%、35.67%,主要分布在西部2个林场(八达岭林场、松山林场)和东部2个山区乡镇(千家店镇、珍珠泉乡)。3)延庆区森林火灾蔓延风险(森林资源)在小班、村屯、乡镇尺度上均无极高风险区域,中高风险区域在小班、村屯、乡镇尺度上分别占比0.80%、2.85%、1.79%;蔓延风险(人口)在村屯和乡镇尺度上均无极高和中高风险区域,小班尺度上无极高风险区域,仅有9个中高风险小班,中蔓延风险区域在小班、村屯、乡镇尺度上分别占比34.97%、51.19%、42.25%。【结论】森林火灾高发生危险小班以杨树、刺槐、柳树的人工林为主,高蔓延危险小班以蒙古栎天然林、油松人工林、侧柏人工林为主,中高蔓延风险(森林资源)小班以油松和落叶松的人工林为主,中蔓延风险(人口)区域主要分布在东部4个山区乡镇(珍珠泉乡、千家店镇、刘斌堡乡、四海镇)。
【Objective】In this study,an assessment framework for forest fire spread risk(including occurrence hazard,spread hazard,and spread risk)was established,to carry out multi-scale(subcompartment,village,township)forest fire spread risk assessment in Yanqing District of Beijing based on GIS technology.The study aims to provide a basis for forest fire management in Yanqing District,which could minimize the occurrence hazard of forest fire and the loss caused by the spread of forest fire.【Method】Based on the subcompartment data of the 2019 forest resources second-class survey,forest fuel data,population data,30-meter resolution digital elevation data and meteorological data,the forest fire occurrence hazard assessment index system was constructed from two aspects:difficulty in wildfire sources management and ease degree of ignition.The forest fire spread hazard assessment index system was constructed from four aspects of forest fuel,meteorological factor,topographic factor and fire behavior.The subjective and objective weighting method of AHP and entropy weight method were used to determine the index weight,and the weighted comprehensive evaluation method and the area weighted average method were used to calculate the multiscale occurrence hazard and spread hazard index.According to the natural break point classification method,the grade is divided.Based on the risk assessment framework of“hazard-exposure-vulnerability”,the forest fire spread risk was evaluated from two aspects of destroying forest resources and threatening life safety.【Result】1)The comprehensive weight of difficulty in wildfire sources management reached 0.7713,which was the main factor affecting the forest fire occurrence hazard.The comprehensive weight of fire behavior was 0.4032,which was the main factor affecting the forest fire spread hazard.2)The forest fire occurrence hazard in Yanqing district gradually decreased from plain to mountainous area,and the high occurrence hazard areas accounted for 0.89%,0.52%and 7.48%in subcompartment,village and township scales,respectively,mainly distributed in the plain area around the urban area.The spread hazard gradually increased from plain to mountainous area,and the high spread hazard areas accounted for 46.19%,58.73%and 35.67%respectively in subcompartment,village and township scales,mainly distributed in two western forest farms(Badaling Forest Farm and Songshan Forest Farm)and two eastern mountainous towns(Qianjiadian Town and Zhenzhuquan Township).3)The forest fire spread risk(forest resource)in Yanqing district was not extremely high risk area in subcompartment,village and township scales,and the medium-high risk areas accounted for 0.80%,2.85%and 1.79%in subcompartment,village and township scales,respectively.The forest fire spread risk(population)was had no extremely high or medium-high risk areas in village and township scales.There were no extremely high risk areas in subcompartment,only 9 mediumhigh risk areas in subcompartment,and the medium risk areas accounted for 34.97%,51.19%and 42.25%in subcompartment,village and township scales,respectively.【Conclusion】The high occurrence hazard subcompartments were mainly in Poplar,Robinia pseudoacacia and Willow plantations.The high spread hazard subcompartments were mainly in Quercus mongolica natural forest,Pinus tabuliformis plantations and Platycladus orientalis plantations.The medium-high spread risk(forest resource)subcompartments were mainly in Pinus tabuliformis and Larch plantations.The medium spread risk(population)areas were mainly distributed in four eastern mountainous towns(Zhenzhuquan Township,Qianjiadian Town,Liubinbao Township and Sihai Town).
作者
王博
杨雪清
蒋春颖
刘冬
陈锋
白夜
刘晓东
Wang Bo;Yang Xueqing;Jiang Chunying;Liu Dong;Chen Feng;Bai Ye;Liu Xiaodong(Key Laboratory of Forest and Grassland Fire Risk Prevention Ministry of Emergency Management School of Ecology and Nature Conservation,Beijing Forestry University,Beijing 100083;Academy of Forestry and Grassland Inventory and Planning,National Forestry and Grassland Administration,Beijing 100013;Yanqing District Forestry and Parks Monitoring Center of Beijing Municipality,Beijing 102100)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2023年第8期90-101,共12页
Scientia Silvae Sinicae
基金
国家重点研发计划(2020YFC1511601)。
关键词
延庆区
森林火灾
蔓延风险
多尺度
地理信息系统
Yanqing District
forest fire
spread risk
multi-scale
geographic information system
