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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

Southeast Tibet Forest Fuel Types and Flammability

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Chinese Forestry Science and Technology 2007年第1期6卷 77-81页

作者： shu lifu ZHAO Fengjun WANG Mingyu LIU Xiaodong WANG Jingsheng Forest Protection Laboratory of State Forestry Administration Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beiiing 100091 P.R.China Beijing Forestry University Beijing 100083 P.R.China Tibet Agriculture and Animal husbandry College Linzhi 860000 P.R. China

Southeast Tibet forest is in east subtropical zone. This region natural environment is unique, influenced by the southwest monsoon, so forest fires are very easy to occur in the dry season. Forest in this region is over mature forest, and accounts for much proportion. Fire season in this area is 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,but to April in an individual arid year. Most of the fires in this area are surface fires, crown fire, can occur after long time drought. Ground fires do not occur in the region.

关键词： forest fire forest fuel flammability

Target Controllability of Multi-Layer Networks With High-Dimensional Nodes

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1999-2010页

作者： lifu Wang Zhaofei Li Ge Guo Zhi Kong School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China

This paper studies the target controllability of multilayer complex networked systems,in which the nodes are highdimensional linear time invariant(LTI)dynamical systems,and the network topology is directed and *** influence of inter-layer couplings on the target controllability of multi-layer networks is *** is found that even if there exists a layer which is not target controllable,the entire multi-layer network can still be target controllable due to the inter-layer *** the multi-layer networks with general structure,a necessary and sufficient condition for target controllability is given by establishing the relationship between uncontrollable subspace and output *** the derived condition,it can be found that the system may be target controllable even if it is not state *** this basis,two corollaries are derived,which clarify the relationship between target controllability,state controllability and output *** the multi-layer networks where the inter-layer couplings are directed chains and directed stars,sufficient conditions for target controllability of networked systems are given,*** conditions are easier to verify than the classic criterion.

关键词： High-dimensional nodes inter-layer couplings multi-layer networks target controllability

Advance in Forest Fire Prevention

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Advance in Forest Fire Prevention

Study on Forest Fire Occurrence in China

作者： Tian Xiaorui,shu lifu,Niu shukui, Liu Xiaodong,Hu Haiqing,Wang Mingyu

＜正＞This paper reviewed the status and the development trend of forest fire prevention discipline,as well as compared the research difference in this area both in domestic and *** results indicated that there is a b...

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Chinese Forestry Science and Technology 2002年第3期1卷 59-64页

作者： shu lifu TIAN XiaoruiResearch Institute of Forest Ecology, Environment and Protection. Chinese Academy of Forestry. Beijing 100091, China,

China is not rich in natural forest sources. Owing to natural and historical factors, forest fires have long been frequenting China. Forest fire prevention is the most important of all. Forest fire prevention and controlling have long been held as a very important factor in our ecological plans. Taking china 's special geographical location, topography, climate and the distribution of forest sources into consideration, we have every reason to believe that forest fires in China have their own special env...

关键词： Forest Fire Fire Environment Fire Occurrence

Forest Fires and Prevention Strategies in Northwestern Region of China

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Chinese Forestry Science and Technology 2003年第2期2卷 66-72页

作者： TIAN Xiaorui shu lifu WANG MingyuResearch Institute of Forest Ecology, Environment and Protection, Chinese Academy of ForestryBeijing 100091, P.R. China

The paper described the natural conditions and forest types in Northwestern Region of China. Most forests in the region are distributed in subalpine areas. It is important to protect the existent forests in the region for maintaining ecological balance. According to the statistics results of 1991~2000, the paper analyzes the forest fires distribution and fire severity. Annually the numbers of forest fires range from 52 to 240. The incidence rate of forest fires in Northwestern Region is under 0.33 per t...

关键词： forest fires Northwestern Region fire management strategy

近40a大兴安岭漠河县林火行为指标变化特征

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东北林业大学学报 2012年第12期40卷 76-80,98页

作者：杨光邸雪颖舒立福东北林业大学哈尔滨150040 中国林业科学研究院森林生态环境与保护研究所

基于加拿大火险天气指标系统,研究了1971—2010年间大兴安岭漠河县林火行为指标的变化特征。结果表明:近40 a研究区的初始蔓延指标(ISI)、有效可燃物指标(IBU)、林火天气指标(IFW)和火灾难控程度指标(RSS)所分别代表的林火蔓延速度、林... 详细信息

基于加拿大火险天气指标系统,研究了1971—2010年间大兴安岭漠河县林火行为指标的变化特征。结果表明:近40 a研究区的初始蔓延指标(ISI)、有效可燃物指标(IBU)、林火天气指标(IFW)和火灾难控程度指标(RSS)所分别代表的林火蔓延速度、林火释放能量、林火强度和林火持续时间具有相同的年代变化特征,即20世纪70年代为林火行为的严峻期、80～90年代出现了一次明显的年代际转型,伴随着这次年代际的转型,21世纪后的林火行为更加严峻,表现为林火蔓延速度增快、能量释放增大、林火强度增强、火持续时间增长。

关键词：大兴安岭漠河火行为年代际

Fire Environment Mechanism of Lightning Fire for Daxing'an Mountains

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Chinese Forestry Science and Technology 2003年第4期2卷 18-24页

作者： WANG Mingyu shu lifu TIAN Xiaorui LI JieInstitute of Forest Protection, Chinese Academy ofForestrv Forest fire management office. State Forestry Administration

Lightning fire is one of natural fires; its mechanism is very complex and difficult to control. Daxing'an Mountain is the main region that lightning fires occur in China. Research on lightning fires indicates that special fuel, dry-storm weather and high altitude form the lightning fire environment. Lightning fires have close relation with lights. When lightning occurs, especially dry-lightning which brings little precipitation with surface temperature growing and fuel dehydrating, these often lead to l...

关键词： forest fuel fire resource dry storm lightning fire weather

北京门头沟区主要林分类型地表火行为模拟研究

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北京林业大学学报 2022年第6期44卷 96-105页

作者：李炳怡刘冠宏舒立福中国林业科学研究院森林生态环境与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

【目的】地表火是最常见的林火类型,直接影响植被更新和生态系统的养分配置与循环。反映林火行为的常见指标有火蔓延速度、单位面积发热量、火强度和火焰高度。根据实际林分和立地条件进行火行为模拟,可以揭示林火发生条件,并有效判断... 详细信息

【目的】地表火是最常见的林火类型,直接影响植被更新和生态系统的养分配置与循环。反映林火行为的常见指标有火蔓延速度、单位面积发热量、火强度和火焰高度。根据实际林分和立地条件进行火行为模拟,可以揭示林火发生条件,并有效判断树冠火发生的可能性,为林火的预防和扑救决策工作提供科学依据。【方法】选取北京市门头沟典型林分(刺槐林、油松林、侧柏林)为调查对象,每个林分设置5块样地,共计15块样地。通过野外调查获取可燃物载量(灌木可燃物、草本可燃物、1时滞可燃物、10时滞可燃物、100时滞可燃物)、林分因子(第一活枝下高、第一死枝下高、树高、胸径、郁闭度)和立地因子(海拔、坡度、坡向、坡位)数据,使用BehavePlus6软件,基于气象参数和可燃物参数,模拟不同燃烧条件下不同林分类型的火行为指标,分别为地表火蔓延速度、单位面积发热量、火线强度和火焰长度;使用R语言进行主成分分析,根据贡献率探讨林分因子、立地因子和可燃物因子对火行为的潜在影响。【结果】侧柏林、刺槐林和油松林的可燃物总载量分别为15.35、17.59、15.28 t/hm^(2),其中易燃可燃物载量(即上层枯叶、易燃草本、1时滞可燃物)分别是4.55、4.41、6.18 t/hm^(2),分别占林分总可燃物载量的29.6%、25.1%、40.4%。防火期内门头沟区的平均风速为2.2 m/s(7.9 km/h),地表火蔓延速度油松林>侧柏林>刺槐林,速度分别达11.5、11.1、8.0 m/min。单位面积发热量油松林>侧柏林>刺槐林,分别为23 091、21 155、18 413 kJ/m;火强度油松林>侧柏林>刺槐林,分别为4 426、3 882、2 468kW/m;油松林火焰高度变化范围分别是0.89~3.40 m、1.34~2.91 m、1.78~3.88 m,同等条件下火焰高度油松林>侧柏林>刺槐林;8级大风天气下(风速17.9 m/s,64.4 km/h),地表火行为的模拟结果会略有改变,侧柏林的火蔓延速度更快、火强度更高,油松林、刺槐林次之。根据主成分分析的因子贡献度,分别得出影响3种林分火行为的主成分,侧柏林、刺槐林与油松林的第1与第2主成分分别为可燃物构成(可燃物载量及影响其分布的地形因素)与林分因子、可燃物构成与可燃物含水率、林分因子与可燃物含水率。【结论】(1)易燃可燃物载量是影响林分火行为的关键因子。(2)可燃物含水率对火行为指标的数值起决定作用,可燃物含水率的临界值影响林火发生类型。可燃物湿润时无论风速大小,林地难以起火;可燃物干燥时处于易燃状态,大风天气时容易发生蔓延快、强度高的地表火。(3)可燃物连续性是决定地表火发展成为树冠火的关键因素,火焰高度大于第一活/死枝下高,极有可能从地表火发展成为树冠火,扑救难度极大。建议需定期修枝割灌,清理林下可燃物,降低火险。

关键词：可燃物载量细小可燃物地表火行为火强度 Rothermel地表火蔓延模型