Design of county-level soil information system based on Web-GIS

Abstract: Science research and production practice have accumulated a large number of soil data, which is the valuable essential data for practice and research. It is significant for sustainable land use to enhance soil information management and sharing. But currently the construction of county level soil information system is facing many issues such as the high cost, difficult to maintain, and performance bottlenecks, etc. In this paper, a low-cost open-source Web GIS platform (MapGuide Open Source) was adopted to design and develop a county-level soil information system (CLSIS) for Lishu county based on the second soil survey database and other soil data in Visual Studio.Net. The system development was divided into four stages: system requirement analysis, system design, system implementation and system testing. The system was designed as a three-tier Server/Brower open application system. Client tier may be a browser terminal or a management terminal. Web tier, deployed on the internet information server, was responsible for receiving requests from browsers, passing the requests to the application server and returning the response to browsers. Application tier was composed of a GIS server (MapGuide Open Source 2.1), a database server and a remote Web Map Service (WMS) component. The database was organized as the attribute database and spatial database, respectively. The attribute database includes the soil basic information table, soil physical properties table, soil chemical properties table, geomorphology table, and land use and administrative table. Among all spatial data, the soil, topography, land use and administrative maps are vector layers, but the precipitation and temperature are stored as raster format. The server-side of CLSIS provided map services, feature services, render services and image services. The functions of server-side were implemented by C# and MapGuide Server API in Visual Studio.Net. The browser-side programming is applied with fusion flexible page layout solution, which has better flexibility, scalability and response speed. Fusion framework is an expanded JavaScript library derived from OpenLayers and JXLib. The system built up a dynamic contact with Google WMS, facilitating the switch of base map among the standard, satellite, hybrid and terrain. Google WMS enhanced the visual effect and intuitive feelings of CLSIS. The system maintenance and management is mainly done by MapGuide Maestro, which is a client software based on Client/Server structure. The centralized management makes system maintenance and upgrades more convenient. CLSIS realizes the map navigation, map services, feature services and thematic mapping functions. By utilizing these functions mentioned above, users can conveniently query and browse soil resources and other relevant geographic background informations for Lishu county. The available soil data include soil type, soil texture, soil parent materials, soil organic matter, the thickness of humus, pH value, total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, available potassium, trace elements and soil water retention, etc. The operation result shows that the system reaches a good balance between cost of development/maintenance and performance. This system will be a basic county level soil information platform for further expansion in the application of multiple fields.