关键词: 黑龙江, 大兴安岭, 雷击火, 人为火, 变化趋势, 对比分析

Abstract:

Objective: This study aims to provide a scientific basis and reference for the targeted fire management and rational formulation of fire prevention and control policies in the study area by comparing and analyzing the differential changes in the occurrence patterns of lightning fires and human-caused fires in Daxing’an Mountains, Heilongjiang Province. Method: Based on the forest fire data in the study area between 1966 and 2021, lightning fires and human-caused fires were categorized by fire cause, and the differences in the occurrence of lightning fires and human-caused fires at different time scales, changes in patterns and trends in the fire season were compared and analyzed by means of ANOVA and linear fitting. Result: A total of 1 887 forest fires occurred in the study area between 1966 and 2021, of which 932 were lightning fires and 503 were human-caused fires, accounting for 49.39% and 26.66% respectively. There were significant differences between lightning fires and human-caused fires on different time scales such as year, month and period of occurrence. The number of lightning fires in the study area showed a fluctuating increase, while the number of human-caused fires showed a fluctuating decrease, especially after 1987, the number of lightning fires in the study area gradually increased compared to that of human-caused fires, but the overall change in the total number of forest fires in the study area was not significant. In terms of fire area, the overall area of lightning fires had an increasing trend in the study area, while the area of human-caused fires and total forest fire had a decreasing trend. The lightning fires in the study area mainly occurred in June and July, while human-caused fires occurred mostly in April and May. There was a trend of significant increase in the number of lightning fires during summer forest fire prevention period, but the change in the area of lightning fires was not significant. However, there were significant decreases in the number and area of human-caused fires during spring forest fire prevention period. From the perspective of occurrence time, the period of high incidence of human-caused fires in the study area was from 10:00 to 15:00, while the period of high incidence of lightning fires was from 12:00 to 17:00. The difference between lightning fires and human-caused fires at different time scales resulted in a change in the fire season in the study area, with the lightning fire season showing a delayed expansion, the human-caused fire season showing a gradual shortening, and the total forest fire season showing a contraction and shortening. Conclusion: Due to climate change and fire prevention policies, there are obvious differences in the occurrence patterns between lightning fires and human-caused fires in Daxing’an Mountains, Heilongjiang Province. Targeted fire prevention and control efforts based on the occurrence characteristics and changing trends of different fire types are a necessary prerequisite for effectively reducing forest fire risks in the study area.

Key words: Heilongjiang, Daxing’anling, lightning fire, human-caused fire, trend, comparative analysis