一、为何需要洪泛区管理洪泛区对早期的美国居民有很大吸引力,因为它土壤肥沃并靠近河道,可为日常生活提供丰富的食物和充足的水源。随着岁月的流逝,洪泛区内小贸易站和农场发展起来,而且许多已成为大城市。1987年,17500个居民区中处于 Why floodplain management is needed Floodplains are attractive to early American residents because they are fertile and close to the river and provide abundant food and adequate water for everyday life. As the years went by, small trading stations and farms in the floodplain developed and many became megacities. In 1987, 17,500 neighborhoods were in place