An Operational Rice Field Mapping Tool Using Spaceborne Sar Data

Rice is of significant importance for many tropical countries, both as a staple food and as an agricultural product for international trading. Crucial parameters for yield forecasting are the area of the rice fields and the rice growth status. Spaceborne microwave remote sensing is a technology that permits mapping and monitoring of the rice growth over large areas at regular intervals. This paper presents the main achievements of a project that was carried out in the framework of ESA's Data User Programme, and which was dedicated to rice field mapping in tropical areas. The major result of the project is SARscape, a tailor-made software for land applications, which can be used for rice mapping and rice growth monitoring. It utilises ERS and Radarsat-1 Synthetic Aperture Radar data (and in the near future, ENVISAT ASAR data) as input. The modular SAR processing chain is embedded in the commonly used ArcView (Environmental Systems Research Institute, Inc.) Geographic Information System environment and allows novice users, even if they are not at all familiar with SAR technology, to generate thematic products such as rice maps and to monitor the rice growth in an automatic way. Expert users may interactively change the processing chain as they wish. This user friendly tool and the GIS environment allows rapid access to up to date rice information and the direct combination with already available spatial data. This is relevant for natural resource management and monitoring as well as entrepreneurial decision making in the field of rice trade. The performance of this system and the resulting products are shown for two sites located in Sri Lanka and Vietnam.