SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Integration of SSURGO maps and soil parameters within a geographic information system and nonpoint source pollution model system 
Authors:Di Luzio, M., J.G. Arnold, and R. Srinivasan 
Journal:Journal of Soil and Water Conservation 
Article ID: 
URL (non-DOI journals):http://www.jswconline.org/content/59/4/123.short 
Broad Application Category:interface tool and/or other software 
Primary Application Category:GIS interface, GIS utility, or other type of interface/utility 
Secondary Application Category:soil data resolution effects 
Watershed Description:7.9 ha Scarborough Creek watershed (north central Texas) 
Calibration Summary: 
Validation Summary: 
General Comments:Describes development of SSURGO input data function for AVSWAT; shows example of SSURGO vs. STATSGO input effects on sediment, N & P losses 
Abstract:Computer based frameworks, including geographical information systems (GIS), associated digital data sets and integrated hydrological models, have become essential tools for the practical deployment of watershed assessment projects and ultimately for providing support for water quality protection and conservation. Within these frameworks digital soil information and data sets play a key role in defining the spatial distribution of important hydraulic variables and consequently of fundamental hydrologic functions connected with NPSs (Nonpoint Sources) and their modeling. This paper illustrates background and results from the development of a GIS based tool required for the use of Soil Survey Geographic (SSURGO) data sets (an undergoing development and delivery effort of digital soil maps by the Natural Resources Conservation Service) and primarily designed in specific support of the Soil and Water Assessment Tool (SWAT) model and its applications in the United States. The tool is developed as an addition or extension to the model companion, the ArcView GIS interface in its latest version (AVSWAT-X) which is designed to define watershed hydrologic features; store, organize, and manipulate the related spatial and tabular data; and analyze management scenarios. Within this framework the tool expedites the otherwise complex inclusion operations of the SSURGO data, such as: (1) downloading, via the Internet, up-to-date SSURGO data sets (version I or II); (2) processing and managing variously formatted data sets in order to create the needed digital soil maps; (3) generating and/or storing the required soil physical and hydraulic model input parameters derived from pedo-transfer functions; and (4) seamlessly including them in any watershed modeling framework. Besides the operational advantages, the tool addresses the trend of employing soil maps with increasing detail in order to improve the landscape representation and reduce the modeling drawbacks involved with the aggregation of the spatial input. Soil map features with unprecedented detail along with the elaborated attributes have a potential for enhancing modeling assessments in support of water quality programs (i.e. Total Maximum Daily Load) at the watershed as well as stream reach scale, as indicated in basic yet important highlights in the paper.