Impacts of different forest fire management policies and fuel treatment models on forest fire risk in boreal forest of China

Forest fuels are the material basis of forest fires and the main factor in the spread of fires. The current global warming has led to an increase in the effective fuel load in the global boreal forests, and the long-term implementation of the fire suppression policy will lead to a continuous accumulation of fuels in the forests, which will further increase the likelihood of the occurrence of mega-forest fires and the risk of such fires. This challenge has prompted different countries and regions to shift away from monolithic fire suppression policies to practising effective fuel regulation measures in order to strike a balance between reducing the risk of wildfires and protecting ecosystems. This study utilises the LANDIS PRO model to investigate the effects of fire management policies and fuel regulation measures on fire risk in high-latitude boreal forest region of China over 100 years using a 10-year time step. The results show that (1) Fire suppression policies accelerate the accumulation of coarse and fine fuels (by 19.05 % and 9.28 %, respectively) and increase the potential average fire intensity of the area (by 58.81 %) compared to no fire suppression policies; (2) Implementation of mechanical removal, prescribed burning and mechanical removal plus prescribed burning under the fire suppression policy reduces the area of high-intensity fires in the region and thus significantly reduces the forest fire risk (by 17.37 %, 13.37 %, and 21.18 %, respectively); (3) Implementing a fire suppression policy and mechanical removal plus prescribed burning on 3.0 % of the area every 15 years are supposed to be the optimal fuel treatment program for the region, which resulted in significant reductions in total area burned, and low, medium, and high-intensity area burned by 23.34, 26.23, 23.73, and 22.87 %, respectively, when compared to no fuel treatment. This study found that fire management policies have a greater impact on fire risk than fuel regulation measures and that reasonable fuel control can help reduce the area of high-intensity fires in the region. This study aids to provide a scientific basis and data support for formulating forest fire management policies and selecting fuel control methods in high-latitude boreal forests of China.