基于MODIS数据的火点监测指数方法研究  

Firemonitoring method of FPI-NDVI based on MODIS data

作　　者：周利霞[1] 高光明[1] 邱冬生[2] 黄宝华[3] 

机构地区：[1]中南大学地学与环境工程学院,长沙410083 [2]中国科学院地理科学与资源环境研究所数据中心,北京100101 [3]烟台市国土资源局,烟台264003

出　　处：《火灾科学》2008年第2期77-82,共6页Fire Safety Science

摘　　要：根据火点辐射与背景辐射的差异及MODIS数据火灾监测原理,利用MODIS数据22通道(火点辐射)和31通道(背景辐射)亮温构建了一个火点指数FPI。且只有当植被覆盖率达到一定程度时才会发生火灾的情况,利用归一化植被指数(NDVI)对其火点提取精度进行了修正,去除了地表不是植被、或植被稀少的不足以引起火灾的区域,有效减少了因裸土或城市热岛引起的误判。就南方几省2008年3月和黑龙江2004年10月15日特大森林火灾的情况,提取了几种地物地FPI、NDVI值,分析了FPI、NDVI值与不同地表类型的关系。其中,云是干扰火点FPI值的最大因素,地表植被是干扰燃烧植被的最大因素,并确定这两个地区的FPI和NDVI的阈值。经过分析,相对于MODIS绝对火点识别算法,其精度及提取速度上都有提高。The present research intends to introduce the author＇s fire-monitoring method of FPI--NDVI, or a fire point index- FPI index by using the fire point radiation MODIS data and the 22 channels as well as the 31 channels （background radiation）. According to the fire-monitoring principle and the difference between the background radiation and fire point radiation, fire accidents can take place usually only when the vegetation coverage reaches a certain extent. It is just for this reason that we have revised the conditions of the fire-occurrence and excluded the possibilities of fire-causing disasters by removing the areas with no vegetation and the places with scarce vegetation, for it is necessary to remove the liability for the bare soil or the urban thermal islands to get on fire. By taking the fire that took place in Heilongjiang province on Oct. 15, 2004, as an example, in particular, this paper has drawn a few kinds of geographical features of the principle and analyzed the values of NDVI as well as the relations between the different surface types. Next, we have taken cloud as the biggest factor that helps to define FPI and the NDVI threshold value with the vegetation being the key factor influencing the fire burning. Three strong points can be found in the use of MODIS absolute fire point recognition algorithm, which can be illustrated as follows： first of all, it is the noise ingredient for the effective attenuation-detecting instrument; secondly, it may have some counter-balanced influence on the air movement in a certain degree; third, it helps the fire-detectors＇ narrow their scanning attention. Thus, it can be concluded that the suggested method helps enhance its monitoring precision with greater extraction speed.

关 键 词：遥感 MODIS FPI 亮温 NDVI 

分 类 号：S771.8[农业科学—森林工程]