城市蔓延
Relying on cities for markets, however, can have drawbacks. For example, in England, south Sussex was famous for growing tomatoes for the London market that were delivered by train. The arrival of railways in the 19th century at first stimulated growth of market gardens in certain areas by providing quick access to the city, but it eventually allowed commuting residents to move there and turn many market garden areas into suburbs. Urban sprawl still eats up farmland in urban regions. Buying the rights to develop farmland from the farmers solved this problem in Suffolk County, New York.