CORE PROBLEMS OF URBAN LAND PROTECTION
用生态学原理找出中国城市土地利用和保护中的严重问题，根源在于无限城市发展与有限土地的关系处理不当，提出通过识别土地核心与弹性功能、建立核心系统来保护土地。
The purpose of the paper is to find out the problems existing in the urban land protection and propose new idea,new methodology and new institution for urban land protection.With ecological principles and methodologies,the paper argues that there are some serious problems in urban land use and protection in China.The source of those problems is that the relationship of the infinite urban development and the finite land use is not rightly treated.A workable way to deal with this relationship is to identify the core and flexible functions of the land, protecting the core ones and multi—using the flexible ones.The system integrity and habitat of land could be the core functions of the land,so a core system of the land must be established and protected based on the core functions,mainly on the habitats.The paper concludes that the relationship of the urban development and land use must be reviewed and the methodology and institutions of land use innovated.