城市是区域政治、经济、文化和科技中心,聚居着大量人口,集中并不断创造着巨大的社会物质和精神财富,是交通运输、商品流通、信息集散的枢纽及各级行政首脑机关所在地,也是流域防洪救灾的基地。同样的灾害,城市比农村的经济损失大得多,而且对某些“生命线”设施(如供水、供电、供气、交通、通信、粮食)以及危险品储仓等来说,其损失更难以用经济价值来估算。因此,保证城镇 Cities are the centers of regional politics, economy, culture and science and technology. They live together with a large number of people, concentrate and continuously create huge social material and spiritual wealth. They are also hubs for transportation, commodity circulation and information gathering and distribution, and are also the seat of administrative agencies at all levels. Basin flood control and disaster relief base. In the same disaster, cities have far greater economic losses than in rural areas, and their loss is more difficult for certain “life-line” facilities such as water, electricity, gas, traffic, communications, food storage, etc. Use economic value to estimate. Therefore, to ensure the town