Simulation of surface fire behavior of Pinus tabuliformis forest in Ming Tombs Forest Farm in Beijing

ObjectivePinus tabuliformis is a typical coniferous forest in North China, which is prone to forest fires. By simulating the surface fire behavior of Pinus tabuliformis, it can provide a scientific basis for forest combustibles management, forest fire prevention and fire fighting.

MethodTaking Pinus tabuliformis forest as the study objective, we simulated the surface fire behavior with BehavePlus5.0 software.

ResultThe fuel load of 1 hour timelag, 10 hour timelag, 100 hour timelag and shrub accounted for 78%, 5%, 4% and 13%, respectively. According to the research date, the average value of the surface fire spread rate of Pinus tabuliformis forest was 2.1 m/min, the average value of the fire line intensity was 270 kW/m, the average value of the height of the flame is 0.95 m, and the average value of the heat per unit area was 7 139 kJ/m². Under the conditions of strong wind and dry weather with 1 hour timelag fuel moisture of 6% and a wind speed of 40 km/hour, the average value of the surface fire spread rate of Pinus tabuliformis forest was 15.1 m/min. The average value of the fire line intensity was 3 278.5 kW/m, and the average flame height was 3.1 m, the average value of the heat per unit area was 12 337.5 kJ/m². Simulation of surface fire behavior study can provide a reference for the pruning height of Pinus tabuliformis.

ConclusionThe results show that 1 hour timelag fuel load was significantly higher than the other type of fuel. The surface fire spreads slowly, the fire intensity was low, the flame height was lower than the first branch, and it was easy to be extinguished under normal weather conditions. The simulation results show that under the condition of low water content, the wind speed of the Pinus tabuliformis forest will significantly increase the surface fire spread speed, which is difficult to extinguish artificially. It is necessary to clean up the surface fuel and reduce the fire risk.