Semantic-model support for geographic information systems

Natural resource management is an important issue that uses large amounts of spatial and temporal data. It is risky to predict the consequences of resource management decisions without accurately understanding the interaction of ecosystems over a large region. A geographical information system describes objects from the real world in terms of location-geographic positions, attributes that are unrelated to position, such as soil type, elevation, and demographics, spatial relationships-how objects are linked, and temporal information-the evolution of both spatial and nonspatial data over time. The authors collaborated on this project to develop a computer environment that enables ecological researchers to analyze and solve problems concerning real ecosystems. Their system brings together and makes accessible data from a variety of heterogeneous databases