回顾了中国应用遥感技术调查评估地震灾害的历史及其进展,经过综合论证,给出了汶川地震5种震害的分类划分标准和灾害遥感调查评估总体技术流程,总结了灾害遥感调查评估各个不同阶段,采用不同遥感信息源和不同遥感技术方法识别不同震害的效果,为汶川特大地震灾中救援和灾后重建提供了决策依据;结合遥感技术发展的趋势和地震灾害的特点,提出了震害遥感调查评估的发展趋势.

Earthquake is one of the most destructive natural disasters in China. For a long tmi e, investigation of\nearthquake damage has been based on field surveys, but disadvantages of this means, such as huge workload, low efficiency, toomuch expense and un-visualized information, make it not practica.l However, remote sensing technique can provide a rapid and effective approach for quick investigation and assessment of earthquake damage, owning to its characteristics ofobjectivity, real-tmi e andmacro-scope view.The history of investigation and assessment of earthquake damage based on remote sensing in China: Sincemid of 1960s, institutes and departments of Chinese Academy ofScienceshave done a lotofwork on quake damage investigation and assessmentand accumulated rich experience. Aerialphotographywas carred out forXingtaiquake in 1966, Haicheng earthquake in 1975, Tangshan quake in 1976 and Lancang-Gengma earthquake in 1988 and themornitoring andmapping for earthquake damagewere accomplished in differentscales. Allof these achievementsprovided mi portantscientific basis for decision-making of the earthquake relief and reconstruction. W ith the development of remote sensing technique for decades, this technology supplies technical supportand prioriknowledge for the investigation and assessmentofWenchuan\nquake damage.There occurred open endedRichter8.0 scale earthquake in the county ofWenchuan, Sichuan province onMay12th,2008, which has caused huge destructive losses. In this, the remote sensing technique is used to investigate and paper assess the situation of the earthquake damage. There are five classes of featureswhich can be interpreted according to the remote sensing miageries:(1)the damage degree ofbuildings, like civilian homes, factories, schools, hospitals and so on, which is related to the safety of human life and property directly;(2)the damage degree of structures, such as television towers, chmi neys, oil tanks, power houses and etc., which can indicate the intensity of the earthquake;(3)the damage degree of the lifeline, for example, the highway, railway, bridge, power and communication supply,which are very mi portant for disaster relief and human s life after the earthquake; (4) the field disasters of earthquake,such as landslides, debris flows, ground fissures; (5)the secondary disasters caused by field disasters, like quake lakes,emission of harmful gases. All of these five classes of features are the main data for determinating the intensity of earthquake and the degree ofdamage.The features can be obtained according to differentspectraland spatial resolution of remote sensing mi ageries, through mi age processing and interpretationmethods.Besides, otherkinds ofdata can also be miported for assistant interpretation. Thework flow includes remote sensing mi age processing, human-machine interactive classification, location,qualitative and quantitative information extraction, GIS-supportassessment of earthquake damage,mapping of damaged objects.In this study, the radar mi ages are used.Due to the badweatherafter the earthquake, and the optical remote sensing cannotgetuseful information. As a result, the all-weather radar sensor can provide lots of information and the 1m spatial resolution radar mi ages have played an mi portant role in the investigation. Certainly, the optical remote sensing mi ageries also played an mi portant role. Using kinds of remote sensing mi ages, the abundace of landslides, collapse debris flows,the rate ofbuilding damages, the situation ofquake lakes and road damage are interpreted.In conclusion, remote sensing technique can play an mi portant role in the investigation and assessmentofearthquake damage. Of course, remote sensing application inWenChuan quake shows some shortcomings, and itmay be mi proved and developed in five aspects as follows.(1)It is mi portant to select mi ageries and high spatial resolution mi ageries are significant.(2) The basic database isneeded to be built. (3) Quick interpretation techniques should be developed. (4)It ismore practical to use human-computer interactive interpretation extract earthquake information. (5) In investigation of earthquake damages, data process techniquesof3D rebuildwillquicklybe developed and remote sensing, GIS andGPS techniqueswillbe combined and applied to the investigations inwider and higher leve.l