林火

• It is accepted that combustible factors ( vegetation , type of forest and ventilation ) , temperature , climatic factors ( relative humidity , wind ( speed ) and days of coutinuous drought ) , and terrain factors ( slope , aspect and altitude ) considerably affect forest fire , but human burning activity is still considered as the key factor of wildfire
  可燃物中林下地被物，树种和与闭度，气象因子中气温，相对湿度，风和连续干旱日数，地形因子中坡向，坡度和海拔对林火灾害影响较为显著，但人野外用火行为是导致林火发生的关键因素。
• This thesis has preliminary designed a forest firefighting expert system of existing stand heilongiiang area . it uses wndows 2000 as platform , vsual c - 6 . 0 as tool , sql server as p1atform of accessing data and also reference many advanced expert system technology . the system based on firefighting expert knowledge , used expert system technology to develop a knowledge database a technique database
  该系统建立在windows2000平台之上，以visualc + +为工具，以sqlserver为数据存储平台，并考虑国内外一些先进的专家系统的技术建立起来的。该系统是以林火专家知识经验模型为基础，利用专家系统技术，建立了知识库、方法库、模型库及其推理和求解系统。
• The model can be made into difference equation of the temperature field that can be used to simulate calculation ; then we can get the set of edge point , and we can have the function of the fire line , and we can also have the burned area , the length of fire line and the space of fire area ; it also come to the conclusion that the main factor of forest fire is convection heat transfer
  经差分处理，得到进行模拟计算的一组温度场计算方程；由边界点条件，求出边界点的集合后，拟合得出火线函数，积分后可得到时刻火场的过火总面积、火线长度和火场形状，同时进一步证实了对流传热方式是影响林火蔓延的主要因素。
• According to the law of different forest stand can arise different forest fire , based on the existing forest distribution at the badaling forestry center , the area percentage of different forest types , forest age , crown density and slope for each sub - compartment were analyzed , and based on the different characteristics of each sub - compartment , some rational methods of fire prevention were put forward
  摘要本论文基于不同的林分能引起不同的林火特性规律，针对北京八达岭林场林分状况，统计分析了各林班不同林分类型、林龄、郁闭度、坡度的面积分布百分比，根据不同林班林分特点，提出了合理的营林防火措施。
• In this dissertation a typical area was selected as a case study , which is the tuqiang forest bureau , including two forestry farms , namely , yuying and fendou , covering more than 1 . 2 10s ha , it is also one of the most severely burned bureaus during this fire . based on the widely investigation of the background information in the study area , and supported by the geographic information system ( gis ) and remote sensing ( rs ) , the two digital forest stand maps ( 1987 and 2000 ) and dtm data were overlaid and the spatial and attribute database were produced . according to this , basic characteristics and changing of landscape structure and spatial pattern were widely and thoroughly analysed
  论文选择位于大兴安岭北坡图强林业局的育英和奋斗两个林场作为研究区(该区是1987年重过火区，总面积12万多ha ) ，在对研究区基本情况广泛调查的基础上，借助于rs 、 gis技术手段，并辅以景观生态学知识的支持，研究了林火迹地森林景观格局及其变化的主要特征，同时运用分布指数、偏相关分析等方法重点探讨了地形因子对格局及变化的影响。
• To day , the burned blank was almost restored . the proportion of forest area increased 47 . 6 % in 1987 to 81 . 3 % in 2000 , among the forest landscape patch types , coniferous is the dominant , about 47 . 6 % , which is the result of the intensive planting after fire
  各景观斑块类型的变化强度迥然不同，林火迹地已基本恢复，并基本处于良好的发展状态，目前研究区主要乔木林(针叶林、阔叶林、针阔混交林)面积已占研究区总面积的81 . 3 ，演替顶级群落针叶林已达47 . 6 。