重大的自然灾害给人类带来的伤害是巨大的。我国人口众多、气候多变、地质地理条件复杂、生态环境脆弱，是世界上受害最严重的国家之一。自然灾害已成为我国国民经济持续、稳定、协调发展的重大制约因素。为此，“第三届全国减轻自然灾害学术研讨会”５月７日～９日在北京召开 Huge damage caused by major natural disasters is enormous. China is one of the most victimized countries in the world due to its large population, changing climate, complex geologic and geographical conditions and its fragile ecological environment. Natural disasters have become a major constraint on the sustained, stable and coordinated development of our national economy. To this end, “the Third National Symposium on Natural Disaster Mitigation” was held in Beijing on May 7-9