Assessing The Influence Of Biophysical And Anthropogenic Variables On Southwest Sichuan Forest Fire Hazard

Recently,two serious wildfire accidents in southwest Sichuan have aroused widespread concern for forest fire prevention technology in China.To explore the influence of natural factors and anthropogenic factors on forest fire potential harmfulness over fine landscape scale and temporal vicissitudes.A series of simulation and statistics research are carried.Based on the historical statistics analysis of climate change,the meteorological conditions that continuous high temperature,low humidity and windy caused by atmospheric circulation anomalies are one of the essential reasons for extreme high Fire Risk Index(FRI)or catastrophic forest fire accidents in the same period/year.Before and after the fire,the air pressure,air temperature,humidity,wind speed and evaporation will continuously increase and then decrease(or opposite)with different cycles.In addition,the correlation between FWI and Muli forest fire frequency is significantly larger than that of FFDI.Based on FlamMap model of Xichang city,the different fuel clearing cases were simulated.The anthropological fuel clearing can break the horizontal continuity and reduce the potential harm,of which is closely related to environmental wind speed,combustivities,topographical attributes,as well as clearing intensity and location.The higher the ambient wind speed,the more obvious the treatment effect is.Clearing the weed shrub land that is usually fire-prone area with large horizontal continuity and highly flammable is better than that of clearing the forest litter.Additionally,there is stronger wind mutation,higher spread rate on spread trend in valley zone.The weeds and shrubs clearing and the fires prevention in valley zone should be considered preferentially.Based on FlamMap model of Mu Li County,the effect of roads,land use,fuel on the forest potential fire behaviors were analyzed,it was founded that more broad or dense road can greatly limit the forest potential fire behaviors and mega fires.Moreover,land use and roads greatly changed by human in Muli County have significantly altered the time-space layout and harm of the potential fire behavior in Muli County.