Analysis And Risk Assessment Of Forest Surface Fuels In Ili River Valley,Xinjiang

Objective:To analyze the current situation and distribution characteristics of forest surface fuel load in Ili River Valley of Xinjiang,and to divide and analyze the flammability of surface fuel of main forest types in Ili River Valley.At the same time,the forest fire prevention and control divisions in various regions of the Ili River Valley were classified,and corresponding control measures were proposed for different regions and forest types.Methods:Through the forest fire risk census project,all standard sites in the Ili River Valley area were investigated.Through field investigation,on-site weighing of surface fuel,and collection of surface fuel samples,the surface fuel load of the main forest types was calculated.The surface fuel moisture content,ignition point,calorific value and other data of each forest type were measured in the laboratory,and the flammability of each forest type was sorted by principal component analysis.According to the risk index data of combustibles and meteorological conditions in the Ili River Valley area,the risk of surface combustibles is calculated,and the disaster reduction capacity of surface combustibles is calculated according to the disaster reduction capacity index data such as fire prevention material reserve rate and fire professional team infrastructure compliance rate.Combining the forest fire risk level and the forest fire disaster reduction capacity level,the prevention and control area of the Ili River Valley is graded.Results:(1)There are 11 main forest types in the Ili River Valley,which are Picea schrenkiana natural forest,Betula tianschanica natural forest,Populus iliensis natural forest,Haloxylon ammodendron natural forest,Tamarix chinensis natural forest,Spiraea salicifolia natural forest,Caragana sinica natural forest,Sabina procumbens natural forest,Salix saposhnikovii natural forest,Picea schrenkiana plantation,Populus iliensis plantation,of which the most widely distributed forest type is Picea schrenkiana natural forest.The distribution of surface fuel load in different forest types is different.The surface load of 6 shrub forest types such as Tamarix chinensis natural forest and Haloxylon ammodendron natural forest is less than 15 t/hm~2,and the surface load of 5 forest types such as Populus iliensis plantation and Picea schrenkiana plantation is higher than 20 t/hm~2.In general,the fuel load of arbor forest type is relatively high.(2)The comprehensive score of surface fuel flammability of Salix saposhnikovii natural forest,Tamarix chinensis natural forest,Populus iliensis plantation and Caragana sinica natural forest was the highest.The comprehensive scores of surface fuel flammability of three forest types of Picea schrenkiana natural forest,Betula tianschanica natural forest and Spiraea salicifolia natural forest are lower.(3)The prevention and control areas in the Ili River Valley are divided into the first-level input areas:Chabuchar Xibe Autonomous County,63 regiment;the second-level input areas are 66 regiments,67 regiments,79regiments,and Kekedala City;the third-level input areas include Huocheng County,Xinyuan County,Zhaosu County,Turks County,61 Regiment and other regions.The four-level input areas include Yining City,Yining County,62 Regiment and other areas.Conclusion:(1)The surface fuel load of each forest type has a certain relationship with the site conditions.When the same forest type has the same forest age conditions,the surface fuel load increases with the increase of stand density.When the stand density of the same forest type is the same,the surface fuel load increases with the increase of forest age.The surface fuel load of the same forest type is different when it is in different slope directions.The surface fuel load is the largest in the southern slope and the smallest in the northern slope.The surface fuel load is different when the same forest type is at different slope positions.As the slope position gradually increases from the lower abdomen to the upper abdomen,the surface fuel load of the plot gradually decreases.(2)Salix saposhnikovii Forest,Tamarix chinensis Natural Forest,Populus iliensis Plantation and Caragana sinica Natural Forest have strong flammability and high risk.The surface fuel flammability of the three forest types of Picea schrenkiana natural forest,Betula tianschanica natural forest and Spiraea salicifolia natural forest is weak and the risk is low.(3)The possibility of forest fires in Chabuchar Xibe Autonomous County and 63 Regiment in Ili River Valley is the largest.It is necessary to focus on improving the ability of forest fire disaster reduction and regularly clean up forest surface fuels.