篇首语

进入本世纪初,全世界65亿人口中超过半数已生活在城市中。人口向城市的流动似乎不可能停止,也不会减缓。中国的城市化速度居全球首位．每年大约有1500万人移居到城市里。城市化提供给人们新的选择和经济机会．但对环境的影响也是巨大的。正如乌尔夫·兰哈根教授所说,“城市消耗了大量的自然资源并且排放出大量的垃圾。新城的规划为实践可持续城市发展提供了难得的机遇。尽量减少排放及其他负面的环境影响是对新城建设的共同挑战。新城的建设也为规划设计提供了一个充满潜力的舞台,来规划设计功能良好．有吸引力和宜居的城市景观。”

In the beginning of this century, the majority of the world＇ s six and a half billion people live in cities. The flow of people towards cities seems unlikely to cease, let alone slow. China has the most rapid urban growth in the world; approximately 15 million citizens a year move to cities. This urbanization offers people new choices and economic opportunities but the environmental impact is enormous. As Professor Ulf Ranhagen said,＂ Due to their increasing demographic weight, cities consume inordinate amounts of natural resources and emit tons of waste. Planning for new cities offers a ＂window of opportunity＂ to implement sustainable urban development. Minimising emissions and other negative environmental consequences is a common challenge of all such projects. New cities also present an opportunity to design workable, attractive, and liveable cityscapes.