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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

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

Forest Fire Environment and Characteristics in Northeastern China

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Chinese Forestry Science and Technology 2007年第4期6卷 62-66页

作者： ZHAO Fengjun shu lifu WANG Mingyu LIU Xiaodong Institute of Forest Protection Chinese Academy of Forestry Beijing 100091 P.R.China Beijing Forestry Universitry Beijing 100081 P.R.China

Forest fires occurrence is influenced by many factors, such as inter-annual weather variations and regional fuel distributions. Fires occurrence in different forest region has distinct spatial and temporal characteristics. The paper studied the natural forest fire environment in Northeastern China, as well as forest fires occurrence, burned area and fire seasons in Northeastern Forest Region. The result shows that more than 50% of annual burned area occurred in Northeast China Forest Region. Main fire seasons in the region are spring and autumn. Fires occurrence in spring is larger than that in autumn. There are few fires in summer. The authors' suggestions for fire management department are to emphasize the fuel management, improve the roads conditions, and enhance the fires control ability.

关键词： forest fire Northeastern China fires occurrence burned area

Analysis of Original Causes of Reed Fires in Zhalong Nature Wetland Reserve in Heilongjiang Province

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Chinese Forestry Science and Technology 2006年第1期5卷 57-61页

作者： WANG Mingyu shu lifu TIAN Xiaorui WANG Zhicheng Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry The State Forestry Administration＇s Key Open Laboratory of Forest Protection Beijing 100091 P. R. China Institute of Forest Protection of Heilongiiang Province Harbin 150040 P. R. China

In recent years, serious reed fires occurred in Zhalong Nature Reserve in Heilongjiang Provincein China. From 19th to 28th of March 2005, 12 fires occurred in Zhalong Nature Reserve, and the firesspread to Qiqihaer City, Duerberte Mongolian Autonomous County, Lindian County and Daqing *** burned area was about 18 666 ha. Meteorological factor was the leading factor of its fire environmentin Zhalong Nature Reserve, which came into being for a long time. Long-term drought and shortage of rainmade the reed and meadow withered and yellow and thus greatly reduced the water content of witheredfallen leaves and humus. Much fuel was accumulated and became dry, thus forming the fire *** in Zhalong Nature Reserve were mainly strong surface fires accompanied by the spread of undergroundfire. It was extremely easy for reed to burn and spread very quickly. Once a fire broke out, it could spreadrapidly to a scene of large fire area, and sometimes it could burn for a long time. Due to lack of correctunderstanding of the wetland fire and inconvenient wetland traffic, it was unable to find and put outwetland fire in time to save life and property early.

关键词： reed wetland fire burning Heilongjiang China

Effect of Freezing Snow Disaster on Forest Fuel and Fire Behavior in Southern China

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Chinese Forestry Science and Technology 2009年第2期8卷 63-70页

作者： WANG Qiuhua shu lifu DAI Xing’an WANG Mingyu ZHAO Fengjun Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 100091P.R.China Central South Forestry Science and Technology University Changsha 410000P.R.China

After freezing snow disaster,stands of Pinus massoniana,Cunninghamia lanceolata. Liquidambar formosana,Cinnamomum camphora and Phyllostachys pubescens and new burned areas in Hunan Province were surveyed by setting field *** content and fuel load were measured by sampling and fire behavior(such as rate of fire spread) was *** results showed that fuel load got doubled instantly,fuel thickness enhanced,fuel continuity swelled and water content of fuel decreased as shrubs and herbs die...

关键词： freezing snow disaster forest fuel fire environment fire behavior