B-CGMS Project : ESA International Symposium at Lleida – 1999 (Spain) Agricultural Research Centre - 16/09/99 - 1 - A WEB-BASED MAPPING APPLICATION TO LINK A CROP MODELLING SYSTEM (B-CGMS) AND A GIS DATABASE BUFFET D. 1 , OGER R . 1 , DEHEM D. 2 , TYCHON B. 2 ,VEROUSTRAETE F. 3 , WOUTERS K. 3 1 Centre de Recherches Agronomiques (CRA), Chemin de Liroux, 4; B-5030 Gembloux; Belgium 2 Fondation Universitaire Luxembourgeoise (FUL) 3 Vlaamse Instelling voor Technologisch Onderzoek (VITO) Introduction The aim of the B-CGMS project is to elaborate an integrated information system providing estimation of crop yields, at a regional scale in Belgium, using an agro-meteorological model (CGMS) and satellite data. One particularity of this integrated system is the link of the Crop Modelling System with a Geographic Information Systems (GIS) Database (soil, annual land cover, crop calendar, simulation units, administrative limits,…), through a Web-based mapping application. In this way all Crop Modelling System data and GIS information are available in real-time on Internet by customers and end-users. For scientific users this access is very important during calibration and validation phases of the crop simulation model. Moreover they require an access to the most current data available. For end-users, contents depend on their own needs and data must be accessible easily anywhere. This paper gives an overview of the strategy adopted by the Agricultural Research Centre to develop an Internet Mapping Application in the framework of the B-CGMS project. Methods The link between a crop model and a GIS can be done to build and control input information, or to take advantage of model results. In the framework of the B-CGMS project, this link is important for both situations. Geographic Information Systems are tools to analyse geographic situations through their computer representation with geo-referenced data. The traditional GIS assumes that the system consists of a single software package and data located on a single machine. This situation no longer meets the realities of many GIS projects, which today are often multi-agency, multi- disciplinary, multi-platform, and multi-software (Streinke, 1997). The rise of the Internet provides a flexible way to resolve this problem. The Internet is based on a client/server philosophy, a GIS Server and a GIS client user. Table 1 illustrates the five categories for Internet Mapping application proposed by Fitzke et al. (1997). They differ from each other in the GIS operations they provide. Table 1: Categories of Internet Mapping applications and their functionality (Rinner, 1998). Data Management Visualization Retrieval GIS Analysis Geodata Server X Map Server X X Online Retrieval System X X X Online GIS X X X X GIS Function Server X X X For the B-CGMS project, a compromise solution between Online GIS and GIS Function Server was made. Online GIS offers access to analysis functions and data of a remote GIS via the Internet. A GIS Function Server allows clients to use remote GIS functions on their uploaded data or to download GIS functions for local processing.