Spatial Fluctuation of Forest Fires and Their Response to Global Change

Forest fires have circles and frequency in time. This paper utilizes the historical forest fires data (1980-1999) in Heilongjiang province, and calculates the centroids of annual fire points and annual fire scars, the coordinates of centroids are denoted in geographic coordinates. We study the fluctuation of the centroids using spectrum analysis method. Results show: the centroids of forest fires scars fluctuate along the axis of East Longitude 126.97°and North Latitude 49.63°, and the fluctuation has clear circle. The circles along Longitude and latitude are both 3.3a. The extreme values in East, West, South and North are 128.68°E, 52.82°N, 123.08°E, 46.86°N respectively. The centroids of forest fires points fluctuate along the axis of East Longitude 127.90°and North Latitude 48.69°, and the fluctuation has no clear circle. The extreme values in East, West, South and North are 129.22°E,50.37°N,125.18°E,47.28°N respectively.