THE ELEMENT SOIL AS A BASIC COMPONENT IN A DIGITAL GEOGRAPHIC INFORMATION SYSTEM (CELL SIZE, ACCURACY, DIGITIZATION)
Abstract
Digital geographic information systems are increasingly being used to input, store, analyze and retrieve natural resources information. The data capture and storage of analog information is basically performed using two types of data structures, cell and polygonal data structures. To evaluate the impact of cell size in inventory and mapping accuracies, detailed soil survey maps corresponding to eleven sections in Wabash Township, Tippecanoe County, Indiana, were digitized and rasterized into 0.0025 ha cells. These data were then computer aggregated into several increasing cell sizes. Inventory and mapping errors were quantitatively estimated for each of these data sets. These estimates were used to select and recommend appropriate cell sizes for digital geographic information systems at different levels of detail. The Indiana state soil association map and the general soil map of Oruro, Bolivia were manually digitized, projected to the Albers equal area cartographic projection and rasterized using 25 ha cells, which is one of the recommended cell sizes for the regional level of detail and the scales of the maps utilized. To demonstrate the importance of soils in planning and management decision making activities, several interpretive soil maps were generated rapidly and accurately. These data were computer generated by reclassifying the original data and grouping the map units into meaningful classes of use. High quality products were obtained using the High Level Image Processing System (HLIPS) IBM 7350.
Degree
Ph.D.
Subject Area
Agronomy
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.