information (Caldeira and Pinto, 1998), especially mechanistic types of models like GOSSYM and GLYCIM. Knowledge of soil physical properties is needed for various kinds of In general, both dynamic and static types of data are environmental studies, including crop simulation where the intended users are agronomists, consultants, and growers. However, acquiring required to run a crop model. A dynamic data set inand tabulating a complete set of soils analysis data for a particular cludes information about weather (minimum/maximum region is expensive and laborious. This paper describes the constructemperature, solar radiation, precipitation, and wind tion of a web-based soil physical properties database to meet data run), cultural practices (type and rate of fertilizer and requirements of users of cotton (Gossypium hirsutum L.) and soybean herbicides; date and amount of irrigation), initial soil [Glycine max (L.) Merr.] crop simulation models (GOSSYM and NO 3 , percentage organic matter, and initial soil water GLYCIM, respectively) in addition to providing a generic data file content. A static data set includes information on crop of soil physical properties. The data are comprised of undisturbed variety and soil physical properties like soil bulk density, samples of 1074 soil horizons (or about 300 sample sites) collected saturated hydraulic conductivity (K s ), soil moisture refrom farmers' fields using a tractor-mounted hydraulic probe. Stantention curve, and soil texture. Soil physical properties dard laboratory analyses were performed to determine the various soil physical properties. An Oracle8 relational database managementare generally treated as static properties unless fields system was designed and implemented to store and deliver the soil are subjected to severe soil erosion, soil deposition, or physical properties using a client/server approach. A Perl database aggressive land-leveling processes, and databases coninterface was used for the server-side database connectivity to build taining these data have been reported in the literature the soil files. The database accepts queries on several attributes, in-