Analysis And Research On Forest Fire Risk Assessment Based On GIS

ABSTRACT:Forest fires have caused huge losses to human life and property,so forest fire prediction and risk assessment becomes very urgent and necessary. At present domestic forest fire risk assessment system is not well-directed,and the development of the system is at a initial stage under the actual circumstances in various cities.On the base of summaried research results of the existing domestic and international forest fire risk assessment system, this paper does some useful and exploratory research on forest fire prediction and risk assessment relying on the project of "Research and Demonstration on Beijing Comprehensive Risk Assessment and Zoning Technoloy".The specific topics of this thesis are as follows:Firstly,forest fire risk assessment system in the study area is established.According to the certain pinciples of establishment of the index system,analysing the historical data and references,refering to domestic and international forest fire danger rating evaluation system and combined with available data about physical geography,population and economy,the impact factors of the forest fire are classified by three first-level indicators of risk, vulnerability and disaster response capacity and 12 second-level indicators including vegetation,wind,altitude and so on.Secondly,the model of weight algorithm for the indicators factors is proposed. This paper analyzes four common methods of weight calculation:Delphi,AHP, Entropy Method, Grey Reational Analysis.This paper respectively compares to the corresponding advantages and disadvantages.Combined the data obtained in the study area,the system of forest fires within the region is regards as a gray system.This paper adopts the gray correlation analysis method to calculate weight of the impact factors.Thirdly, taking the project of the "Research and Demonstration on Beijing Comprehensive Risk Assessment and Zoning Technoloy"for example,combined with the system requiements and using the related theory of GIS,system ultimately achieves the weight calculation of the indicators factor and composite risk. The results shows that the program runs:the weight results obtained with gray correlation analysis method is reasonable,which indicates the method is suitable for the regional realities. Correlation matrix R generated from the process can also see association level among the impact factors.These can be provided a reference to local decision-makers so that early and accurate prevention efforts can be launched and specific factors should be targeted to take measures to reduce losses.