高级检索

    基于MODIS数据的内蒙古地形因子对火灾分布的影响分析

    Impact of topographic features on the distribution of fire based on MODIS data in Inner Mongolia, northern China

    • 摘要: 了解火灾与地形因子的关系是深入研究火灾空间分布格局、火灾风险科学管理的重要前提。本研究基于MOD14A1/MYD14A1热异常产品数据集提取内蒙古2000—2015年的火点信息,结合研究区DEM数据,提取相关地形因子,并在此基础上分析区域尺度背景下的地形因子与火灾分布关系。结果表明:1)采用均值变点分析法,确定内蒙古地形起伏度的最佳统计单元为0.52 km2;2)火灾分布在地形因子的作用下表现出一定的地形梯度性。火点个数随高程的升高呈现先增大后减小的变化趋势,而火点个数随坡度和地形起伏度的增大呈现逐渐下降的趋势;3)火点分布最多的高程、坡度、地形起伏度区间分别为80~700 m、0°~7°、1~70 m,火灾多发生在高程低、地形平坦、起伏小的地区,这类区域一般人类活动频繁,为火灾的发生提供了机会;4)在火点分布最多的地形区间内,不同土地利用类型上的火点个数分布排序为草地>耕地>林地>其他类型。

       

      Abstract: Understanding the interplay between the distribution of fire and the topographic features is a fundamental concern for holding the regularity of fire distribution and designing strategic fire management plans. In this study, we analyzed MODIS thermal anomalies (MOD14 and MYD14) and DEM data to explicitly quantify relationships between fire and topographic features, with a particular focus on Inner Mongolia during the period of 2000 to 2015, using a moving-window resampling approach. The results showed that: 1) with the support of mean change-point analysis, the curve appeared at the inflection point at the grid of 8×8 mesh size (0.52 km2) for Inner Mongolia relief amplitude; 2) there was a significant terrain gradient in distribution pattern of fire. It was found that the number of hotspots increased at first and then decreased with the rise of elevation, while decreased with the increase of slope and relief amplitude; 3)fire easily occurred in plat areas, the areas with elevation between 80 and 700 m, slope between 0° and 7° and relief amplitude between 1 and 70 m. Human activities are frequent in these plat areas, which provides the opportunity for the fire; 4) grassland was most affected by fire in terms of hotspots, followed by agricultural areas, forests and others. Human beings' frequent actions and rich combustible are the main reasons for fire on grass.

       

    /

    返回文章
    返回