1980—2015年内蒙古森林火灾的时空动态

Studies on the spatial and temporal dynamics of forest fires in Inner Mongolia from 1980 to 2015

【目的】林火是森林生态系统中重要的干扰因子,严重影响着森林的结构与功能。内蒙古大兴安岭是我国重要的森林生态系统之一,从内蒙古地区地域、海拔、火灾原因分布等可能导致火灾的时空因素分析林火灾害,为森林防火和管理提供有力的科学依据。【方法】基于遥感影像,借助ArcGIS 10.2和Origin等软件,分析了1980—2015年内蒙古地区森林火灾特点,结合时间、空间的因素,探讨林火的时空动态规律。【结果】内蒙古地区森林火灾时空上表现出规律性分布。受害森林面积年变化存在周期性规律,周期间隔16 a,且春季为林火高发季节,在进行森林防火的资源调节过程中,火灾发生次数较多的4、5月正处于春分、清明和谷雨时节,应以控制火源为主要内容。此外,月初林火发生概率相对较高,应在该时段提高警惕;林火的发生主要集中在9:00—17:00;多发于呼伦贝尔市、赤峰市、鄂尔多斯市和兴安盟等地区,其中兴安盟过火面积最大,大兴安岭林区火灾也比较频繁。【结论】内蒙古森林火灾频发,过火面积较大,且火灾频发与人类活动及气候特点息息相关。森林火灾主要由人为活动造成,必须严格控制野外火源、生活用火等。建议在掌握内蒙古自治区森林火灾时空动态特征的基础上,加强防火宣传与教育,并运用科学的森林防火措施,制定合理的森林防护政策。

【Objective】Forest fires are an important form of disturbance in forest ecosystems,seriously affecting the structure and function of the forest.The Greater Khingan Range in Inner Mongolia is one of the most important forest ecosystems in China.This region has frequent forest fires,making it a suitable location for determining the temporal and spatial factors that cause fires.This study can provide a strong scientific basis for forest fire prevention and management.【Method】We used ArcGIS10.2 and Origin software to analyze remote sensing images and examine forest fire characteristics in Inner Mongolia from 1980 to 2015.Forest fire dynamics were assessed based on temporal and spatial factors.【Result】The temporal and spatial distribution of forest fires in Inner Mongolia showed a distinct pattern.We observed periodical patterns in annual variations in damaged forest areas with an interval of 16 years.Spring was the season with the highest occurrence of forest fires.During the time period when forest fire prevention resources were being adjusted,forest fires occurred most frequently in April and May(during the Spring Equinox,fresh green and grain rain solar terms),the main contents should be controlling the fire sources.In addition,the probability of forest fire occurrence was relatively high at the beginning of the month,so vigilance should be increased during this time.Forest fires mainly occurred from 9:00 to 17:00,primarily in areas such as Hulunbuir City,Chifeng City,Ordos City and Hinggan League.Hinggan League had the largest burned area and fire occurrence in the Greater Khingan Range forest area was more frequent than that in other regions.【Conclusion】Forest fires in Inner Mongolia are frequent and burned areas are relatively large,with frequent fires being closely related to human activities and climate characteristics.Thus,it is important to strictly control field fire sources and fire-use activities.Based on the temporal and spatial dynamic characteristics of forest fires in the Inner Mongolia Autonomous Region,we suggest that fire prevention propaganda and education should be strengthened and scientific forest fire prevention measures should be used to formulate reasonable forest protection policies.