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Spotting ignition of larch(Larix gmelinii)fuel bed by different firebrands

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Journal of Forestry Research 2022年第1期33卷 171-181页

作者： Guang Yang Jibin Ning lifu shu Jili Zhang Hongzhou Yu Xueying Di School of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Forest Protection Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of ForestryState Forestry AdministrationBeijing 100091People’s Republic of China Research Centre of Cold Temperate Forestry Chinese Academy of ForestryHarbin 150086People’s Republic of China

Spot fire increase the difficulty of fire-fighting and threaten public safety,and therefore it is important to study ignition probabilities of fuel bed by different firebrands,in order to understand ignition mechanisms and analyze the formation of spot *** will provide an important basis for further study to improve the fire-fighting efficiency and reduce *** this study,the ignition probabilities of larch(Larix gmelinii)fuel beds with different moisture levels and packing ratios by diffreent firebrands,including cones and twigs of different sizes,was *** experiments were conducted at different wind speeds generated by *** results show that,regardless of moisture content and packing ratio,ignition probability is zero when there is no *** moisture content and wind speed significantly infuence ignition probability,while packing ratio has almost no *** maximum moisture content at which firebrand ignition occurred was 50%,and ignition probability increased with wind speed and decreased with moisture *** have the highest ignition probability,followed by large twigs and by small *** probability is also affected by firebrand shapes and sizes that determine their potential heat and contact area to the fuel *** empirical models were established to link ignition probability with fuel properties and wind *** study will help clarify the mechanism of spot ignition and reduce corresponding losses.

关键词： Firebrands Wind speed Moisture content Packing ratio Logistic model Larix gmelinii

Spatial and temporal distribution of forest fire frequency and forest area burnt in Jilin Province, Northeast China

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Journal of Forestry Research 2018年第5期29卷 1233-1239页

作者： Qiang Liu Yanlong Shan lifu shu Pingyan Sun shuai Du Forestry College Beihua University 3999 Binjiangdong Road Jilin 132013 People's Republic of China Jilin Provincial Key Laboratory of Forestry and Ecological Environment Beihua University 3999 Binjiangdong RoadJilin 132013 People's Republic of China The Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry State Forestry Administration's Key Open Laboratory of Forest Protection Beijing 100091 People's Republic of China Forestry Department of Jilin Province 3698 Yataida StreetChangchun 130022 People's Republic of China

Forest fires caused by natural forces or human activities are one of the major natural risks in Northeast *** incidence and spatial distribution of these fires vary over time and across the forested areas in Jilin Province,Northeast *** this study,the incidence and distribution of 6519 forest fires from 1969 to 2013 in the province were *** results indicated that the spatiotemporal distribution of the burnt forest area and the fire frequency varied significantly by month,year,and *** occurrence displayed notable temporal patterns in the years after forest fire prevention measures were strictly implemented by the provincial ***,forest fires in Jilin occurred in months when stubble and straw were burned and human activities were intense during traditional Chinese *** city,Jilin city,and Yanbian were defined as fire-prone regions for their high fire *** had the highest frequency,and the fires tended to be large with the highest burned area per *** should thus be listed as the key target area by the fire management agency in Jilin Province for better fire prevention.

关键词： Fire intensity Forest fire Temporal distribution Spatial distribution

Supercritical extracts of forest fuels in Great Xing＇an Mountains

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Journal of Forestry Research 2016年第5期27卷 1143-1151页

作者： Fengjun Zhao Mingyu Wang lifu shu Xiaorui Tian Kezhen Liu Research Institute of Forestry Ecology Environment and Protection Chinese Academy of Forestry Key Laboratory of Forest Protection State Forestry Administration No.2 Dongxiaofu Xiangshan Road Haidian DistrictBeijing 100091 China

Extracts are important components of fuels. Fatty-extracts with high heating value （HV） are hypothe- sized by researchers as positively related to the HV of fuels. The Soxhlet extractor is typically used to extract fatty-extracts but it has shortcomings, including long processing time （8-10 h） and the requirement for large amounts of organic solvent. Supercritical extraction is an alternate and useful technique for extraction of natural products. However, published studies rarely discuss the relationship between extracts and HV. In this study, we assessed the supercritical extracts （SUE） of forest fuels in the Great Xing＇an Mountains. Our results indicated that the optimum conditions for extraction of SuEs were 40-60 mesh, 40-50 MPa, 45℃, 80 min and a CO2 flow rate of 1.5-2.0 dm3/min. The Soxhlet extracts contents and the SuE contents were all related to HV. However, R2 of the coniferous samples （0.8499） and needle samples （0.9722） demonstrated that the correlation between HV and the SuE content was closer. We conclude that supercritical fatty-extracts provide a useful index of the HV of fuels, especially coniferous fuels. SuE data can be used in fire management, for example to estimate the rate of fire spread or fire intensity.

关键词： Forest fire Fuel - Soxhlet extracts Supercritical extracts Heating value. Great Xing'anMountains

黑龙江大兴安岭林区雷击火与人为火发生规律及变化趋势

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林业科学 2024年第4期60卷 136-146页

作者：李伟克舒立福王明玉李威司莉青赵凤君李笑笑周暖阳中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林保护学重点实验室北京100091

【目的】对比分析黑龙江大兴安岭林区雷击火与人为火发生规律的差异性变化,为研究区针对性的开展火源管理及合理制定火灾防控政策提供科学依据和参考。【方法】基于研究区1966—2021年间发生的森林火灾数据,按火因归类筛选出雷击火和人... 详细信息

【目的】对比分析黑龙江大兴安岭林区雷击火与人为火发生规律的差异性变化,为研究区针对性的开展火源管理及合理制定火灾防控政策提供科学依据和参考。【方法】基于研究区1966—2021年间发生的森林火灾数据,按火因归类筛选出雷击火和人为火,通过方差分析、线性拟合等方法对比分析雷击火与人为火在不同时间尺度上的发生差异、规律变化及火灾季的变化趋势。【结果】1966—2021年间研究区共发生森林火灾1887起,其中雷击火932起,人为火503起,占比分别为49.39%和26.66%。雷击火与人为火在发生年份、月份和时段等不同时间尺度上均有显著差异。研究区雷击火数量呈波动增加,而人为火数量呈波动减少的趋势,尤其是1987年之后研究区雷击火数量逐渐高于人为火,但从整体看研究区森林火灾总数变化并不显著。从火灾面积来看,研究区雷击火面积整体呈增加趋势,而人为火和总森林火灾面积呈减少趋势。研究区雷击火集中发生在6、7月份,人为火多发生于4、5月份,且呈现夏季防火期雷击火数量显著增多,但雷击火面积变化并不显著,春季防火期人为火数量和面积显著减少的变化趋势。从发生时段上看,研究区人为火高发时段为10:00—15:00,而雷击火高发期在12:00—17:00。雷击火和人为火在不同时间尺度上的变化差异造成了研究区火灾季节的变动,其中雷击火灾季呈延后扩张的趋势,人为火灾季呈逐渐缩短的趋势,总森林火灾季呈收缩变短的趋势。【结论】受气候变化及防火政策的影响,黑龙江大兴安岭雷击火与人为火之间的发生规律具有明显的差异性,根据不同火灾类型的发生特点和变化趋势,开展针对性的火灾防控工作是有效降低研究区森林火灾风险的必要前提。

关键词：黑龙江大兴安岭雷击火人为火变化趋势对比分析

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近年澳大利亚森林火灾综述

温带林业研究 2024年第1期7卷 42-46页

作者：吴月圆舒立福王明玉中国林业科学研究院森林生态环境与自然保护研究所北京100091 国家林业和草原局森林保护学重点实验室北京100091 济南市林果技术推广和产业服务中心山东济南250099

针对近30年澳大利亚森林资源变化与森林大火发生情况,收集了世界粮农组织(FAO)、全球野火信息系统(GWIS)、美国国家航空航天局(NASA)等有关森林火灾权威机构的原始数据,并进行了统计分析。重点对森林大火发生的原因、产生的影响及对中... 详细信息

针对近30年澳大利亚森林资源变化与森林大火发生情况,收集了世界粮农组织(FAO)、全球野火信息系统(GWIS)、美国国家航空航天局(NASA)等有关森林火灾权威机构的原始数据,并进行了统计分析。重点对森林大火发生的原因、产生的影响及对中国的启示三个方面进行了综合概述。得出了以下主要结论:火因的自然因素为气候干热、桉树林分组成、雷击火频繁等;火因的政治体制因素为联邦制管理松散、近自然思想的森林管理理念、财政投入不足等;火因的历史社会因素为烧荒及林中居住等;火因的人为因素为主观纵火等。森林火灾主要影响为大面积森林损失及大量碳排放和对人类赖以生存的生态环境的破坏。对中国的主要启示为在应急机制、经费保障、科技手段、传统经验等方面加强提高。

关键词：澳大利亚森林火灾火因影响启示

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森林火灾污染物质释放及其影响研究进展

生态学报 2024年第12期44卷 4933-4944页

作者：王明玉司莉青陈锋舒立福赵凤君田晓瑞李伟克李威李笑笑中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林保护学重点实验室北京100091 北京林业大学生态与自然保护学院北京100083

森林火灾是大气中气体污染物和颗粒物的重要来源,可对全球气候系统、大气环境以及生态系统产生重要影响,对全球温室气体和含碳颗粒物释放具有重要的贡献,是推动全球气候变化的重要因素。森林火灾释放污染物已成为区域乃至全球范围内重... 详细信息

森林火灾是大气中气体污染物和颗粒物的重要来源,可对全球气候系统、大气环境以及生态系统产生重要影响,对全球温室气体和含碳颗粒物释放具有重要的贡献,是推动全球气候变化的重要因素。森林火灾释放污染物已成为区域乃至全球范围内重要污染源之一,这些污染物质与辐射、能见度以及温室效应等问题直接相关。准确地描述森林火灾释放的气体和颗粒污染物释放机理、释放总量、时空分布特征、不同尺度的扩散过程模拟,以及对区域大气环境的影响,对于量化森林火灾释放污染物总量及区域影响具有重要意义。基于森林火灾污染物质释放方面的国内外文献,从火灾释放的污染物质对环境的影响、森林火灾释放污染物定量化和传输路径监测的研究方法、污染物质的扩散和运输模型以及跨区域影响等几个方面进行了综述。森林火灾释放的CO、PM_(10)和PM_(2.5)对环境和人的生命安全造成巨大威胁,而且森林火灾释放的污染物质能够随气流长距离传输,不仅对当地的空气造成污染,污染物也能够随着气团进行长距离传输,并在传输过程与当地气溶胶混合,形成跨区域污染。森林火灾释放污染物扩散、传输模拟通过不同模型相互耦合完成,包括可燃物载量估算模型、可燃物消耗和释放模型、污染物扩散传输模型,以及污染物预测和可视化模型等。总结了国内外森林火灾释放污染物质主要研究方法,并展望了今后研究重点:目前我国关于森林火灾释放物质相关的研究尚不足以支撑我国森林火灾温室气体释放、污染物释放等方面的研究,并且我国目前还没有发展出适合于我国的森林火灾污染物释放模型,以及污染物扩散、传输系统。森林火灾排放因子库大多数引用国外研究结果,在一定程度上增加不确定性,缺乏森林火灾对区域大气环境影响的定量化研究。因此,今后我国应加强对森林火灾污染物质释放与影响的研究,尤其是污染物质扩散和传输模型的预测和可视化研究以及排放因子的测量。

关键词：森林火灾污染物大气环境扩散模型跨区域污染

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EFFECT OF LOW TEMPERATURE ON POLLEN VITALITY OF LARIX OLGENSIS

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Journal of Northeast Forestry University 1992年第2期3卷 27-33页

作者： Liu Guifeng Guan Weijun Qi Lizhi Wang Qinggui shu lifu Weng Yuhui Northeast Forestry University Northeast Forestry University China

After the treatment of pollen of larix olgensis at the different low temperature, the pollen vitality was observed by using fluorescent staining method. Several conclusions were obtained: 1) 0℃-3℃ is the best temperature range for storing pollen of Larix olgensis. 2) At the same temperature, humidity is the key factor influencing the pollen vitality. 3) Different clones shows different resistance to low temperature. Among the ten clones 2# clone shows the highest resistance.

关键词： Larix olgensis pollen vitality

Monitoring Forest Fire with MODIS-NDVI Images in Beijing

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Chinese Forestry Science and Technology 2006年第4期5卷 87-92页

作者： TIAN Xiaorui shu lifu WANG Mingyu ZHAO Fengjun Forest Protection Laboratory of State Forestry Administration Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091 P.R.China

Fuel moisture monitoring is an important component of fire danger rating system in fire management. This paper describes the application of NDVI images in monitoring potential fire danger and analyses the relationship between MODIS-NDVI and fire weather index. The series of weather data in Beijing are used in this analysis including fire seasons in spring during 2004 to 2005. Canadian Fire Weather Index (FWI) is selected in this study, because it can properly estimate moisture conditions of live fuel. Fine fuel moisture, drought code and FWI values are generated by using the squared inverse distance algorithm. Strong correlations have previously been observed between FWI variables and NDVI data. The MODIS-NDVI images can be used in fire management as component related with live fuel moisture and fire danger.

关键词： forest fire MODIS NDVI fuel moisture content

Southeast Tibet Forest Fire Environment and Fire Behavior

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Chinese Forestry Science and Technology 2005年第4期4卷 49-53页

作者： WANG Mingyu shu lifu WANG Jingsheng TIAN Xiaorui Research Institute of Forest Ecology Environment and Protection Chinese Academy of ForestyBeijing 100091P.R. China Tibet Agriculture and Animal Husbandry College Linzhi 860000 P.R. China

Forest fags in China are very serious in recent years. Few fires occurred formerly in Southeast Tibet, but now forest fires in this region occur frequently. This natural environment of the region is unique. Forest fires are very easy to occur in the dry seasons due to the influence of the southwest monsoon, Because over-mature forest in this region accounts for much proportion, the forest ecosystem is frail. Once destructed by forest fags, it is very extremely difficult to restore. Fire season in this area is in winter and spring. But in the special year, forest fires can also occur in the hot summer. Fire Season lasts from October to next February, even to April in an individual arid year. Most of the fires in this area are surface fires, and crown fires can occur after long time drought.

关键词： forest fire fuel fire environment Southeast Tebet China