Research on Evaluation of Forest Fire Risk Level Based on GIS and Information Entropy
|School||Sichuan Normal University|
|Course||Cartography and Geographic Information Systems|
|Keywords||Forest Fire Danger Rating GIS Remote sensing Analytic Hierarchy Process Information entropy|
Forest fire disturbance forest vegetation in the area is the most important factor, but also natural, biological, ecological and environmental processes of the potential threat. According to FAO statistics of the 47 national forests, 1881 to mid-1990, the average forest fire zone 6. 73 × 162hm 2, accounting for 0.47% of the world's forest area. Frequent fires also forest degradation in China is an important factor. 1950 to 1997, a total of 1.43 × 10 4 from the forest fires, the fire district 8.22 × 10 6hm 2. Therefore, the prediction and evaluation of the potential factors that affect the fire occurred, to understand the dynamic behavior and analysis of fire, forest fire risk zone is necessary. Remote sensing and GIS based spatial information technology has been widely used in resource surveys take full advantage of the spatial information technology, environmental monitoring, timely, accurate grasp of spatial location distribution and vegetation types in the study area for the forest fire risk evaluation provides new methods and support. Sichuan Shimian study area, GIS technology, remote sensing technology for auxiliary application-level analysis and information entropy technology quantitative evaluation of forest fire danger rating in the study area, the proposed combination of GIS information entropy Methods of Evaluation. This study selected vegetation type, elevation, slope, aspect, away from the neighborhoods near and far, near and far away from the road, the eight factors of the study area, average temperature and average rainfall as a forest fire impact factor using analytic hierarchy process to determine the weight of each factor to fully consider each factor to provide objective information, application information entropy technical amendments to the weight of each factor, the last factor weighted overlay method, a quantitative evaluation of forest fire danger rating in the study area, the fire danger rating is divided into high, higher, , lower and low five. The results show that: the high, higher, middle, lower and low fire risk zone, respectively, accounting for 19.14% of the study area, 30.66%, 31.66%, 14.38%, 4.16%, in line with the normal distribution; relatively high forest fire danger and the area above accounted for 49.80%, should strengthen the management of forest fires in the region; forest fire danger rating geographical differentiation, high in the middle, surrounded by low fire danger rating areas at all levels on the spatial distribution of strong spatial autocorrelation. The spatial distribution of this paper show that forest fire danger rating evaluation method based on the combination of GIS, remote sensing and information entropy technology, can fully analyze and the expression study area forest fire danger rating status quo, the conclusion of the evaluation is more objective, more space targeted for The forestry departments provide a valuable reference for forest fire management, also has a strong potential for application in other areas.