A Digital GeoLibrary: Integrating Keywords And Place Names

A digital library typically includes a set of keywords (or subject terms) for each document in its collection(s). For some applications, including natural resource management, geographic location (e.g., the place of a study or a project) is very important. The metadata for such documents needs to indicate the location(s) associated with a document – and users need to be able to search for documents by keyword as well as location. We have developed and implemented a digital library that supports – but does not require – georeferenceable documents (i.e., documents with reference to geography through the use of a textual place name). Because of their implicit spatial footprint, place names benefit from spatial reasoning and querying (e.g., to find all documents that describe work performed within a five-mile radius of a certain point) in addition to traditional keyword-based search. This paper presents the architecture for a digital library that combines spatial reasoning and selection with traditional (non-spatial) search. The contributions of this work are: (1) the use of a traditional geographic information system (GIS) for spatial processing rather than a specially tailored GIS system or a separate gazetteer and (2) the seamless integration of GIS with our thesaurus-based Metadata++ system, so users can easily take advantage of the strengths of both systems.