台中港防風林區地面燃料型與潛在林火行為之初探

Ground Fuel Types and Potential Fire Behavior of Casuarina Spp. Forests at the Windbreak Zone of Taichung Harbor

本研究參酌目前台灣所發展的地面燃料調查模式，以地表植群的特徵，進行各項燃料參數之測定。透過階層群集分析法，將地面燃料依組成之差異區分台中港防風林區為4類燃料型；進一步使用BEHAVE林火模擬軟體探討各燃料型之林火行為，分別預測出相關林火行為（蔓延速率、單位面積熱量、火焰強度及火焰長度），最後將模擬結果分為3種林火指標燃料等級，結果顯示台中港防風林區大部份（79%）屬於中度以上火行為等級，此等級於林火發生初期須使用消防水線方能抑制火燒，在林火防救上於水源匱乏區域，建議考慮增設蓄水池，以備林火發生時有效抑制火勢蔓延。本研究所得之火指標燃料等級，可提供林區管理者制定出相應之林火防救對策。 Adopting current ground fuel inventory methodology in Taiwan we conducted the present study on modeling surface fuels which based on the property of the surface vegetation types. Using Hierarchical Cluster Analysis technique, 4 fuel types have been classified on Taichung Harbor windbreak forests. All the fuel types were then used as inputs to the BEHAVE plus fire behavior simulation model to simulate the fire behaviors. The result of these simulations show that fire behavior can be rated to 3 levels under the greatest situation of the average wind speed the summer of Taichung Harbor; and by this rating the potential fire behaviors (Surface fire spread rate, heat per unit area, flame intensity and flame length) are displayed. The result shows that most the windbreak forests are moderate fire level which hands are not able to put out the fires. Therefore, we propose that the windbreak forest needs to increase the reservoirs for the place which is shortage of water source, so the potential fire can be effectively suppressed. We conclude that the result not only provide a theory based fuel models for forest manager, but also the way to easier for the forest fire prevention and control.

Adopting current ground fuel inventory methodology in Taiwan we conducted the present study on modeling surface fuels which based on the property of the surface vegetation types. Using Hierarchical Cluster Analysis technique, 4 fuel types have been classified on Taichung Harbor windbreak forests. All the fuel types were then used as inputs to the BEHAVE plus fire behavior simulation model to simulate the fire behaviors. The result of these simulations show that fire behavior can be rated to 3 levels under the greatest situation of the average wind speed the summer of Taichung Harbor; and by this rating the potential fire behaviors (Surface fire spread rate, heat per unit area, flame intensity and flame length) are displayed. The result shows that most the windbreak forests are moderate fire level which hands are not able to put out the fires. Therefore, we propose that the windbreak forest needs to increase the reservoirs for the place which is shortage of water source, so the potential fire can be effectively suppressed. We conclude that the result not only provide a theory based fuel models for forest manager, but also the way to easier for the forest fire prevention and control.