The research purpose of this dissertation is to discuss the development trend and theory of the semantic integration and interoperability of Geography Information Systems on the network ages and to point out that the Semantic-based Spatial Information Grid (SSIG) is the foregone conclusion of the development of the semantic-based integration and interoperability of Geography Information Systems.

Two hierarchical concepts, namely, generalized spatial information grid and specialized spatial informadon grid are proposed by the author.

Architecture and Key Techniques of Spatial Information Grid;

Resources sharing framework of spatial information grid;

Study on resource and environment spatial information grid for southwestern China;

Model for loss assessment of flood disaster based on spatial information grid;

The paper firstly discusses on the basic concept of grid,specially analyses the spatial information grid, and briefly describes the composition,structures and applied method.