Mapping spatial patterns of urban agriculture in Rome (Italy) using Google Earth and web-mapping services

Urban agriculture (UA) has been acknowledged for several positive effects such as access to fresh food, human activities moderation, agro-biodiversity and social and cultural relationships. In the city of Rome due to social and economic trends this kind of activity is spreading, but so far very few attempts have been addressed to inventorying the UA areas (e.g., community gardens, residential gardens, school gardens, illegal vegetable gardens, urban farms, etc.). Some mapping experiences have been carried out but all lack of a well-established methodology to be applied for a complete inventory. In this paper we propose a conceptual framework and methodology for mapping the UA in Rome through Earth Observation techniques by using the concepts of photointerpretation and the features of the most used web-mapping services. Google Earth has been used as a basic tool for visual interpretation and polygon digitalization, while other services have been used for the availability of additional features (e.g., the oblique view of Microsoft Bing Maps). The integration of the web-mapping services combined with ancillary data improved the UA site detection, allowing to define both the land use and the UA typologies. We argue that the integration of the web-mapping services for building urban agricultural land use datasets is cost-effective compared to processing commercial remote sensing images. The inventory can enable administrators to perform analysis about the interactions between agricultural activities and the urban environment, and to enact informed policies for green and vacant urban spaces management. (C) 2016 Elsevier Ltd. All rights reserved.