Abstract: 【Objective】 A study was made for the purpose of warning and tracing the quality safety of vegetables from production to sale by modern information technology.【Method】In this study of vegetables from Shouguang City, the national production and demonstration base of vegetables, the authors mainly addressed the gathering of information on vegetable quality, safety supervision and traceability management in that city, by means of the WebGIS, the Internet of things, bar code identification, and database technology. In this research, the vegetable logistics data acquisition and storage were studied, and the platform construction of the system of vegetable safety warning and traceability was explored.【Result】The authors used the networking data acquisition technology, established a set of attribute database using SQLServer2008 database consisting of data of vegetable production, processing, transport and sale. A set of vegetables safe spatial data were produced by means of GIS, which includes the Shandong road map, Shouguang sampling map, and Shouguang soil nutrient map. On that basis, a set of effective vegetable safety warning and traceability platform was established. The platform consists of a variety of information technology, with consideration of the business needs of the vegetable safe production of Shouguang City. The whole platform is divided into four modules: data query, vegetable quality safety warning, vegetable quality safety traceability, and auxiliary tool. The platform is designed for the following: the vegetable information inputting and editing, vegetable information query, warning traceability, vegetable information stereoscopic display, the best path analysis, vegetable soil nutrient statistics, vegetable soil nutrient interpolation, etc. The real-time early warning system can transmit the information of coordination, temperature, humidity and time to the server with network real-time data acquisition. The platform can also monitor and forecast vegetables temperature, humidity, shelf life, to ensure the quality and safety of vegetables. As for the function of vegetable quality safety traceability, the authors trace the path of logistics and distribution on the map according to the vegetable bar codes and logistics coordinate. To fulfill the path analysis function, one can design the path for the optimum according to the transport of vegetables and destination. The function of vegetables spatial information display can be achieved by means of the vertical surface of stereoscopic display from the soil to the ground and the atmosphere, namely, the integration of three-dimensional space and different times. 【Conclusion】This study demonstrates the process from vegetable production to sale using the GIS technology. The system under discussion is of great help to improve vegetable quality and safety management. To some degree, the system has been proved effective for the government departments concerned for the sake of supervision of vegetable safety.

Key words: WebGIS, the internet of things; quality and safety, warning, traceability