The changing role of remote sensing for land resource assessment in Scotland: lessons for the future

The paper explores the changing role of remote sensing within land resource assessment applications in Scotland over the past 60 years. The objective is to identify key trends and highlight future directions. A wide definition of remote sensing (RS) and resource assessment is adopted, the latter including both tangibles like soils, vegetation and land cover but also intangibles like the visual landscape. The historical period is reviewed in terms of three distinct eras. Firstly, the manual era, during which all mapping and cartography was done by hand. This is illustrated using the Soil Survey of Scotland where RS was essentially used as a support to field mapping techniques. The second era concerns the transition to the digital, where we still used conventional air photo interpretation but combined it with digital mapping. This is illustrated using the Land Cover of Scotland (1988) database, where RS data were used as the primary data source. The third era is the present, the era of the integrated data model. Here we are using RS, particularly in the landscape arena, to support both quantitative landscape analysis and to enable user participation. Each of the illustrative case studies is set out in terms of its relevance to contemporary Government policy (e.g. agriculture, environment, renewable energy) and its cost. Irrespective of their technological contexts (i.e. analogue or digital), these case studies represent significant operational uses of RS and a number of themes emerge: i) the changing role of RS data from intermediate source of information (where they were discarded afterwards) to RS data being both a source and a key part of an integrated database; ii) the degree to which users were involved in developing the applications: from the Soil Survey which was essentially scientist-led, to the mixed model of the LCS88, and towards the current model where the users are very much involved in the specification and development of the information products; iii) the visibility of the data to the users. In the past, users were generally unaware that RS data were fundamental to the production of the information product because they did not see it. Now, in the era of fused databases, the role of RS is much more apparent. The paper concludes by setting out some of the new opportunities for RS data sources, analysis and applications to resource assessment.