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Due to the rocky desertification great damage to the ecological environment, Desertification Region, vegetation restoration work has attracted much attention. Rocky desertification region vegetation recovery massive accumulation of flammable fuels in the initial surface, the forest fire situation is extremely serious. The event of a fire, will cause damage to vegetation, soil and nutrient loss, and speed up the rocky desertification area retrograde succession process, become more severe rocky desertification. Therefore, forest fire prevention work is particularly important in Desertification Region, vegetation restoration work. Stands combustion determines the degree of difficulty of the forest fire prevention work, which affect the success or failure of the rocky desertification area vegetation recovery. This study in Shaoyang County rocky desertification vegetation restoration areas to select five kinds of typical vegetation recovery mode to set the standard manner determined stand valid combustible load, the moisture content of the combustible materials, the moisture escape rate, heat of combustion, and the amount of energy existing 5 planted on the southwestern Hunan rocky desertification area is restored mode (the wetlands loose Chunlin PEPF, side Bo Chunlin POPF, mixed forest PLMF elliottii and Liquidambar and mixed forest LPMF Liquidambar P. orientalis and Liquidambar the Chunlin LFPF) early stand flammability research and simulation based on fire behavior. The following major findings: in the the Shaoyang County Rocky Desertification Ecosystem early stand of vegetation recovery mode, the main effective types of combustibles: Imperata, verbena and some shrubs. The same kind of stand with the the flammability difference within the non-fire season is mainly due to the differences in effective combustible load, moisture content, calorific value and energy existing factors caused the fire season. In Hunan Province, high fire danger season (autumn and winter), 5 plant recovery mode stands valid combustible load (EFL) was relatively large, between 5.16 Dao 9.89 t · hm-2, which side of Bo Chunlin for 9.89t · hm-2. Effective combustibles (EF) relative moisture content of 17.8 to 42.6%, of Imperata and litter side Bo Chunlin moisture small, the moisture escapes a short time, analysis of water rate, burning strong. Elliottii and Liquidambar mixed forest EF average relative moisture content, the moisture escape longest incendiary relatively poor. The main EF combustion calorific value 11.7 ~ 20.8 kJ · g-1; no significant differences in the heat of combustion of the same kinds of EF in different vegetation restoration patterns; stands EF heat of combustion value-weighted average of the difference is small in 17.37 18.03 kJ · g-1 between factor can not be judged as a stand combustion difference. EF total energy of the size of the standing crop Sort: the wet pine Chunlin gt; side Bo Chunlin gt; gt in elliottii and Liquidambar mixed; Liquidambar P. orientalis mixed forest gt; Liquidambar Chunlin. In the low fire danger season (during the growing season) stands EFL than in the range of 5.28 to 10.42t · hm-2, one of the largest wetlands loose Chunlin. EF relative moisture content of 15.5% to 71.2%. Stand in EF to 15.86 17.39kJ · g-1 between the heat of combustion values. EF total energy of the size of the standing crop Sort: the wet pine Chunlin gt; elliottii and Liquidambar mixed forests gt; P. orientalis Liquidambar mixed forest gt; Liquidambar Chunlin gt; side Bo Chunlin. High fire danger season low fire danger season, slash pine Chunlin arbor energy standing for the highest Chunlin, sweet gum trees energy existing amount of the lowest, most flammable fuel types. Stand incendiary, with the existing forest fire spread model simulation of the behavior of forest fires, truly reflect the realities of forest fires. Can be used for command and extinguishing of forest fires. EF combustion characteristics of these stand that, Shaoyang County Desertification Region, five vegetation recovery mode early EF accumulation of stand flammability; including Chunlin combustion than mixed forest. Therefore, it is recommended to choose a mixed forest the rocky desertification ecosystem vegetation recovery, appropriate intensity cleanup on some plants, especially grasses, to reduce EF accumulation, to achieve the purpose of reducing the risk of fire.
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