| Vegetation recovery is very important in rocky desertification area due to its destructiveness to the ecology system. Vegetation recovery is definitely very important for rocky desertification area. But there is more risk of fire disaster in the process of forest restoration because of the accumulating of fuels from vegetation. Fire will reduce vegeration, which leads to water, nutrition loss and soil erosion, and the aftermath is it will make the rocky desertification more sever and affect the burned area for a long period. The combustibility of forest is critical for the success of rocky desertification restoration.The study sites were set in ShaoYang county. The level of effective fuel loading, the speed of water escape, gross caloric value,and effective fuel energy were measured and analysised in order to reaserch the combustibility of the 5 different vegetation restoration stands include Pinus elliottii Pure Forest (PEPF), Platycladus orientalis Pure Forest (POPF), Pinus elliottii and Liquidamba formosana Mixed Forest (PLMF), Liquidamba formosana and Platycladus orientalis Mixed Forest (LPMF), and Liquidamba formosana Pure Forest (LFPF). The result indicates that:the combustibility of the same forests in fireseason and non-fireseason is different. During the fireseason in HuNan province (winter and autumn), the main effective fuel are Imperata cylindrical, Verbena officinalis and some shrub; and the effective fuel loading of all the forests is higher, the number is between 5.16-9.89 t-hm-2; EFL of POPF is the highest among these, which is 9.89 t-hm-2; relative moisture content of effective fuel is between 17.8%and 42.6%; the relative moisture content of Imperata cylindrical and Forest Litter in POPF is the lowest, which has a strong combustibility because of the short time and high speed for water escaping; by contraries, the relative moisture content of effective fuel in PLMF is the highest, and the combustibility is weak. The caloric value of main effective fuel is between 11.7 kJ·g-1 and 20.8 kJ·g-1; it's almost the same among these forests; weighted average caloric value of effective fuel is low, which between 17.37 kJ-g-1 and 18.03 kJ·g-1, can't be the judging factor of combustibility difference to the 5 different forests. The order of effective fuel energy is that: PEPF>POPF>PLMF>LPMF>LFPF.The effective fuel loading of non-fireseason is also high, which ranges from 5.28 t-hm-2 to 10.42 t-hm-2; and EFL of PEPF is the highest. The Relative moisture content of effective fuel is 15.5%-71.2%. The gross caloric value of the 5 forests is 15.86kJ·g-1-17.39kJ·g-1, the order of effective fuel energy is that: PEPF>PLMF>LPMF> LFPF>POPF. The effective fuel energy of arbor in PEPF is the highest in fireseason and non-fireseason, LFPF is the lowest.Based on the combustibility of the forests, using analog simulation on the fire behavior of forests, by the forest fire spreading models reflects the real situation after the forest fire. It could be used in saving and conducting work of forest fire.The features of effective fuel in these 5 forest demonstrates that:due to the accumulating of fuels from vegetation the combustibility of 5 different vegetation restoration stands is high, and pure forests are more combusitle than mixed forests. So choosing mixed forests and reducing the grass for vegetation restoring is the best way to reduce the potential of fire happening, and suitable reduce of certain specises, especially the herbage, is also needed.
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