摘要
Most cropping system models and decision support tools are structured for site-specific (i.e. field- or point-based) simulation and analysis. As the need grows for analyses on crop production and management at local, county, state, national, and even global scales, cropping system models and decision support tools are increasingly structured to provide the capability for area-wide simulation and analysis at a range of spatial scales. A major challenge is the development of a data management system that can provide dynamic access to large volumes of geo-referenced data needed by such applications. The objective of this paper is to present a methodology to develop a Cropland and Soil Data Management system that is capable of automatic data consolidation and integration, and can provide dynamic access to the integrated data by cropping system applications. The Cropland Data Management component of the system is based on the Cropland Data Layer (CDL) products from the USDA National Agricultural Statistics Service and is implemented with seven program modules: Data Requester, Data Fetcher, Data Parser, Geodatabase Builder, Map Service Builder, Map Cache Generator, and Cropland Map Viewer. The Soil Data Management component is based on the Soil Survey Geographic (SSURGO) database from the USDA Natural Resources Conservation Service and is implemented with six program modules: Data Requester, Data Fetcher, Data Parser, Database Builder, Soil Map Generator, and Soil Map Viewer. The approaches and methodology presented in the paper can serve as a reference for those who are interested in developing integrated cropping system applications.