The integration of soil survey maps with Geographic Information Systems (GIS) allows for an almost infinite level of collaboration across disciplines that use information related to soil databases. The ability to link databases with geospatial delineations and to store unique information for individual delineations creates the opportunity for this information to serve many other areas of study.
These researchers from Iowa State Univ. created a Quaternary geologic map by categorizing soil descriptions into a geologic context and joining the attributes with the Soil Survey Geographic (SSURGO) database in ArcGIS (ESRI, Redlands, CA). The resulting map communicates many of the spatial intricacies of the Des Moines Lobe landform with 15 map units based on geologic units. The display of these map units shows detailed features of ground moraine, stagnation moraine, glacial lakes, outwash, and loess deposits. Qualitative visual assessment shows that the resulting Quaternary geologic map has generally good agreement with existing Quaternary geologic maps while including finer detailed information and user-controllable scale. On the basis of these results, the researchers envision widespread use of this method.
The researchers found that categorization of soil map units with respect to geologic unit successfully created a detailed Quaternary geologic map for the Des Moines Lobe, showing strong agreement with the existing Quaternary geologic maps while adding a user-controlled level of scale.
There are differences between existing Quaternary geologic maps and the researchers’ Quaternary geologic. Increased dialog between disciplines and ground-truthing could help resolve these differences and perhaps answer questions that have remained for both groups. For example, the level of detail surveyed by soil scientists could help geologists decipher ambiguous or complicated areas of multiple glacial advances.
The researchers claim that after the development of keys that relate soil survey terminology to information of geologic interest, the use of the soil survey will be a quick and easy reference for geologic inquiry. The same concept applies to any discipline affected by soil properties. Within the soil survey, soil series are expected to consistently describe a defined range of soil properties. Those definitions should be used to create a spatially linked database for the attributes of interest. In the future, other soil properties could be added and studied spatially at practically any scale.
Adapted from“Using Soil Surveys to Map Quaternary Parent Materials and Landforms across the Des Moines Lobe of Iowa and Minnesota” by Bradley A. Miller, C. Lee Burras, and William G. Crumpton.
Published in Soil Surv. Horiz. 49:91–95 (2008).