地理信息系统的应用模型是其空间决策支持系统的核心，因而对应用模型和模型库管理系统的开发以及应用模型实现技术的研究，已成为地理信息系统深入应用的关键所在。通过对地理信息系统技术发展及其功能的回顾，分析了目前GIS应用模型实现的一系列有关技术问题，并针对存在的问题，提出了关于模型的有效管理，模型的共享和安全，GIS与应用模型的集成，模型库与数据库的通信机制，模型的可视化及其互操作等问题的解决方案与途径，最后以长江水体的二维污染扩散模型为例，阐述了模型实现的方法和技术。

It is quite important for the GIS's applied models to support their special decision system. So the development of the management system of the applied models, their base and the research of the realizable technology has become the key to GIS's further application. In the paper, series of technical problems in relevance to GIS's applied models have been analyzed in retrospect of GIS's technical development and its function. At the same time, relevant programs and approaches have been put forward in order to solve such problems as model's effective management, sharing and security, the integration of the GIS and applied models, the communication mechanism of model base and database, model visualization its mutual operation and so on. At the conclusion of the paper, in combination with the "Ninth-five" plan, "the demonstration system for the spacial information share and service of the environment protection will be built", the model realization of the approcah and technology has been described, with an example of the planar pollution and diffusion models in Yangtze River.