Patterns of Forest Fire Point and Area Distribution in Inner Mongolia at Different Spatial Scales

The variability, correlation and scale effects of the distribution of forest fires and areas in Inner Mongolia at two spatial scales, namely, league/city and banner/county, from 1981 to 2020 were investigated by choosing methods such as spatial variability analysis(coefficient of variation), global spatial autocorrelation, hotspot analysis and scale analysis of variance(ANOVA). The results showed that the coefficient of variation of forest fire area at the league/city scale showed an increasing trend; the coefficient of variation of forest fire area at the banner/county scale showed a decreasing trend, and the spatial variability at the banner/county scale was even larger. the Moran's I index of forest fire points in the whole bureau was 0.99 for 40 a. Moran's I index at both spatial scales showed a decreasing trend; among them, the maximum value of Moran's I index at league/city level was 0.46 in 1991–1995 and the maximum value of Moran's I index at banner/county level was 0.61 in 1986–1990. The banner/county scale more significantly shows the spatial distribution differences of forest fires and the hotspot types of forest fires in smaller areas; the league/city scale reveals the overall spatial distribution pattern of forest fires, and the hotspot types obviously lack diversity. The hotspot areas at the league/city scales are mainly distributed in Hulunbeier City and Xing'an League; the cold spot areas are not obvious. Hot spot aggregation areas existed in all flag/county scales, and the level of forest fire occurrence was high. The order of scale variance at different spatial scales was: banner/county > league/city. The contribution of the variance of forest fire area at the flag/county scale to the overall variance of the whole Inner Mongolia Autonomous Region is much higher than that at the league/city scale. The forest fire area at the dual spatial scales from 1981 to 2020 shows a certain distribution pattern, and the spatial agglomeration of fire points shows a weakening trend. There is not exactly a positive correlation between forest fire points and forest fire area. The number of fires in the eastern part of Inner Mongolia is higher than that in the central and western parts due to natural and anthropogenic factors, and the relevant departments should continue to increase fire prevention efforts. As the scale decreases, the spatial distribution pattern of forest fires becomes more obvious and the degree of aggregation increases, so it is essential to further narrow the scope of the study.