Utilizing GIS in the Soil Survey Program

Soil science has evolved over the last century. New tools allow both the scientists who create soil surveys and the customers who use them to better analyze and utilize the data. The advent of Geographic Information Systems (GIS) has greatly improved our ability to analyze and spatially depict soil data. 

In the strictest sense, a GIS is a computer system capable of assembling, storing, manipulating, and displaying geographically referenced information, i.e. data identified according to their locations. Practitioners also regard the total GIS as including operating personnel and the data that go into the system. 

Soil surveys are now being created in digital format to utilize the power contained in GIS technology. In addition, NRCS is currently converting original published surveys into digital format. This process is called Soil Survey Geographic Database (SSURGO) certification. The SSURGO surveys allow customers to utilize soils information in a variety of ways. Custom data queries and map making are just two of the advantages of using a GIS for soil survey analysis.

The Arizona Soil Survey Program is utilizing GIS technology to support the needs of many customers both internal and external. NRCS employees are now able to use the digital soil information to create highly accurate conservation plans in a more timely manner. Soil maps can be created in a fraction of the time that it used to take. In addition, custom soil data queries can be made and the results can be shown spatially using real world locations. 

Customers outside the agency are finding ways of using the digital soil data as well. In January 2000, a map depicting shrink/swell potential for soils in the Phoenix area was published in a newspaper article on construction problems associated with shrink/swell soils. This map was made available on the web and had thousands of viewers. In February 2002, a similar map for the greater Tucson area was printed and posted on the web. These GIS products are playing a valuable role in the education of consumers and developers on the issue of expansive soils.