基于GIS的中国土壤分类专家系统设计

土壤系统分类以定量化指标划分土壤类型,为土壤自动分类系统的建立提供了依据;地理信息系统(CIS)的应用扩展了土壤空间信息表达的能力,为实现土壤分类自动制图提供了手段。本文着重模仿专家的思维过程,探讨如何实现土壤自动分类。(1)采用面向对象的方法表达专家经验规则、诊断层和诊断特性知识,并在此基础上提出了决策树的构造方式和推理方法;(2)从土壤系统分类专家的知识表示和推理机的构建两个方面,提出了土壤分类专家系统(SCES)的体系结构、土壤自动分类与地理信息融合的方法和基于GIS和专家系统(ES)的土壤自动分类检索系统的框架结构。

DESIGNING OF SOIL CLASSIFICATION EXPERT SYSTEM BASED ON GEOGRAPHICAL INFORMATION SYSTEM

The Soil Taxonomy offers a theoretic basis for establishment of a soil classification expert system (SCES) , which divides soil types according to quantitative soil indexes. The Geographical Information System (GIS) technology offers an effective tool for automatic mapping of soil classification. This paper concentrates on reasonable methods of developing SCES and automatic soil mapping by simulating thinking processes of soil classification experts and using the GIS technology. Firstly, object-oriented methods are used to express the experience and knowledge of soil diagnostic horizons and diagnostic characteristics of soil classification experts; and on such a basis, decision tree structures and consequence ways are discussed. Then a logic structure of the SCES, methods to combine geographic information with automatic soil classification, and the framework of an automatic soil classification searching system based on GIS and ES are brought forth from the angle of knowledge expression of soil classification experts and construction of an inference engine.