Integrating land-cover data with different ontologies: identifying change from inconsistency

Abstract

Spatially coincident land-cover information frequently varies due to technological and political variations. This is especially problematic for time-series analyses. We present an approach using expert expressions of how the semantics of different datasets relate to integrating temporal time series land-cover information where the classification classes have fundamentally changed. We use land-cover mapping in the UK (LCMGB and LCM2000) as example data sets because of the extensive object-based meta-data in the LCM2000. Inconsistencies between the two datasets can arise from random, gross and systematic error and from an actual change in land cover. Locales of possible land-cover change are inferred by comparing characterizations derived from the semantic relations and meta-data. Field visits showed errors of omission to be 21% and errors of commission to be 28%, despite the accuracy limitations of the land-cover information when compared with the field survey component of the Countryside Survey 2000.

Acknowledgements

This paper would not have been possible without the assistance of those involved in creating LCM2000, especially Geoff Smith. This paper describes work done within the REVIGIS project funded by the European Commission, Project Number IST-1999-14189. We wish to thank our partners in the project, especially Andrew Frank, Robert Jeansoulin, Alfred Stein, Nic Wilson, Mike Worboys and Barry Wyatt. The paper was greatly improved in addressing the comments of anonymous reviewers.