Soil Extent Mapping Tool
Functional Requirements
Revision 1.2
17 January 2006
Org.\Dept.
Signature
Date
NRCS
CEI
Revision 1.2 -Page 1
Revision History
Revision
Date
Originator
Description
1.0
10/03/05
B. Bills
Original version
1.1
10/31/05
B. Bills
Incorporated review comments (edited phase
III requirements).
1.2
1/17/06
S. W. Waltman
Minor edit Page 6 regarding MLRA mapping
symbol
Revision 1.2 -Page 2
Table of Contents
Purpose................................................................................................................................ 4
Definitions........................................................................................................................... 4
Overview ............................................................................................................................. 4
Phase I: Map Tool Launched from OSD Site .................................................................... 5
Use Case.......................................................................................................................... 5
Requirements .................................................................................................................. 6
Data Needs ...................................................................................................................... 7
Phase II: Standalone Map Tool .......................................................................................... 7
Use Case.......................................................................................................................... 8
Requirements .................................................................................................................. 8
Data Needs ...................................................................................................................... 8
Phase III: Map Soil Taxon Concepts ................................................................................. 8
Use Case.......................................................................................................................... 9
Requirements .................................................................................................................. 9
Data Needs .................................................................................................................... 10
References ......................................................................................................................... 10
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Purpose
This document defines the functional requirements for the Soil Extent Mapping Tool.
Definitions
Word
MLRA
Definition
Major Land Resource Area; geographically associated land resource
units utilized by NRCS for management and planning.
OSD
Official Series Description; national collection of soil series
descriptions that serve as specifications for identifying and
classifying soils.
SC Database
Soil Classification Database; contains the taxonomic classification of
each soil series identified in the U.S.
Soil Data Mart
Soil Data Mart; provides online access to spatial and tabular soil
survey data.
soil series
the lowest level of classification in the U.S. system of soil taxonomy.
soil survey area
a discrete area in which soils are mapped for a given project; often,
this area is a county.
soil taxon
a class at any categorical level in the U.S. system of soil taxonomy.
SSURGO
Soil Survey Geographic Database; geospatial datasets of soil map
units and associated tabular attributes such as physical properties and
interpretations.
Overview
The Soil Extent Mapping Tool provides web-accessible national maps of individual soil
series and other soil taxon extents based on the land area of series mapped in the
SSURGO 2.1 data source as provided by the Soil Data Mart. The basic unit shown on
the national series extent maps will be a soil survey area or county. Each map delineation
will be symbolized according to a defined legend of acreage values reported in the
SSURGO 2.1 data source. Map images presented will utilize Macromedia Flash and
internet map services technologies in a standard web browser environment.
The project will be broken into three phases as described below.
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Phase I: Map Tool Launched from OSD Site
Query tools on the existing Official Series Description web site allow users to search for
soil series and view the resultant OSD narratives. In Phase I of this project, the results of
the search will be extended to include access to interactive national series extent maps.
Figure 1. Soil series extent map.
Use Case
View an extent map for a soil series from the Official Series Description web site.
Work-flow scenario:
1. The user visits the Official Series Description web site
(http://soils.usda.gov/technical/classification/osd/).
2. The user submits a soil series query using the existing search tools:
 View OSD by Series Name (with best-match feature)
 View OSDs by List of Series Names (with FTP option)
 Soil Series Name Search
3. The series resulting from the search are displayed to the user with a choice to
view either the extent map, or the narrative (Figure 2).
4. The user chooses to view the extent map.
5. The extent map opens in a new browser window (Figure 1).
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Figure 2. The “View Extent Map” button is presented to the user with the
series search results when using the “Series Name Query” option.
Requirements
1. The map shall display soil survey area, Major Land Resource Area (MLRA),
state/territory, and country boundaries.
2. The map shall support viewing extents of the conterminous United States, Alaska,
Hawaii, and all U.S. Territories.
3. The user shall have the ability to toggle the display (on/off) of MLRA boundaries.
4. The survey areas in which the selected series occurs shall be classified and
symbolized on the map according to the total number of acres of the series in the
area.
4.1. Soil series acreages shall be classified into four categories using the Jenks
Natural Breaks method.
4.2. The colors used to symbolize the categories shall be discernible by colorblind users.
5. When a user identifies/selects a survey area in which a series occurs, the
following information shall be displayed:
5.1. name of the survey area
5.2. total acres of the selected series
5.3. percentage of the survey area that is mapped as the selected series
5.4. percentage of the survey area that is not mapped to any series (ex.
“miscellaneous areas,” “taxon above family,” etc.)
6. When a user identifies/selects an MLRA polygon, the name and mlra_reg_symbol
of the MLRA shall be displayed.
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7. The user shall be able to print a presentation quality copy of the map that includes
marginalia (e.g. information sources and usage notes).
8. The user shall be able to print a tabular report of the selected series’ acreage by
survey area that includes:
8.1. name of the survey area
8.2. total acres of the selected series
8.3. percentage of the survey area that is mapped as the selected series
8.4. percentage of the survey area that is not mapped to any series
Data Needs
The following data will be required to perform the functions defined in the previous
sections:



Soil Survey Area Polygons
Custom summary from Soil Data Mart that provides acreages of series by survey
area and acres of components other than “series” mapped in the survey area
OSD web site (link to existing search functionality)
Phase II: Standalone Map Tool
Phase II improves the efficiency and flexibility of the tool by implementing it as a standalone application rather than as an element of the OSD web site. Integration of the
current OSD web site search-by-series name capabilities directly into the application will
enable users to quickly search and map soil series extents without having to go through
the OSD narrative. Alternatively, a link to the narrative will be provided if the user
wishes to access it.
Figure 3. Standalone series extent map web application with integrated search tools.
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Use Case
Search for soil series and view their extent maps in a standalone application.
Work-flow scenario:
1. The user launches the soil extent map web application.
2. The user searches for series based on name(s).
3. The series resulting from the search are displayed.
4. The user chooses a series for which to display an extent map.
5. The extent map is displayed.
Requirements
In addition to phase I requirements 1-8:
1. The user shall be able to search for soil series by submitting:
a. a series name
b. a combination of one or more letters in the series name(s) and wildcard
characters such as * and ?
c. a list of series names
2. The user shall be given the option of viewing the OSD narrative for a soil series in
addition to its extent map.
Data Needs
The data required to perform the functions defined in this sections are the same as those
needed for phase I.
Phase III: Map Soil Taxon Concepts
In Phase III the application will be expanded to query and generate extent maps for soil
taxon concepts. Specifically, the capabilities to query soil taxonomy found in the current
Soil Classification Database web site (http://soils.usda.gov/technical/classification/scfile/index.html) will
be integrated into the application. For example, the user will be able to query a particular
taxonomic family and receive a distribution map of that family. The interface will include
the option to print a presentation-quality query report that includes a map and associated
summary information.
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Figure 4. Map the extent of a soil taxon.
Use Case
Specify a soil taxon and map its extent.
Work-flow scenario:
1. The user launches the soil extent map web application.
2. Using a series of drop-down pick-lists, the user specifies a soil taxon.
3. An extent map of the specified taxon is displayed.
Requirements
In addition to phase I requirements 1-7 and phase II requirements 1-2…
1. Two methodologies shall be provided for querying soil by taxonomy:
a. search by hierarchical taxonomic classification
b. free-form search on independent taxonomic criteria
2. A hierarchical taxonomic classification builder shall assist the user in defining a soil
taxon through a series of filtered choice lists as described below.
2.1. Choice lists shall be provided for each level of the hierarchy. When selecting a
suborder, great group, and subgroup, the choices available in each level shall be
filtered by the selection made in the parent taxonomic level. For example,
selecting a specific order shall limit the suborder choices to members of that
order.
2.2. In the case of defining a family, the user shall be given a choice of acceptable
values for each family modifier group: particle size, particle size modifier,
mineralogy, CEC activity, reaction, soil temperature, and other.
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3.
4.
5.
6.
2.3. When defining a family, the user may select only one value (or none) for each of
the seven family modifier groups.
2.4. The user may query taxa at any level in the taxonomic hierarchy. For example,
typical queries might include, at a high-level, “Vertisols,” or, at a lower-level,
“Udic Haplusterts.”
The user shall be able to perform a free-form search for soils by typing a combination
of taxonomic elements, modifiers, and criteria. For example, a user may query the
"glauconitic" mineralogy class independent of a complete family classification. In
the same fashion, one may query all vitrandic subgroup modifiers independent of the
great group.
When typing free-form search criteria, use of wildcards such as ‘*’ and ‘?’ shall be
permitted.
The user shall be notified if no matches are found for the taxa or criteria specified.
When mapping the extent of a family, the user shall be able to print a tabular report of
the selected family’s acreage by survey area that includes:
6.1. name of the survey area
6.2. total acres of the selected family
6.3. percentage of the survey area that is mapped as the selected family
6.4. percentage of the survey area that is not mapped to any series
Data Needs
The following data will be required to perform the functions defined in the previous
sections:


Soil Survey Area Polygons
Custom summary from Soil Data Mart that provides:
o acreages of series by survey area
o acres of components other than “series” mapped in the survey area
o complete taxonomic information for each series
References
Keys to Soil Taxonomy, 9th ed.
http://soils.usda.gov/technical/classification/tax_keys/keysweb.pdf
NRCS Official Soil Series Descriptions (OSD) Fact Sheet
http://soils.usda.gov/technical/classification/osd/fact_sheet.html
NRCS Soil Series Classification Database Introduction
http://soils.usda.gov/technical/classification/scfile/introduction.html
Soil Science Society of America Internet Glossary of Soil Science Terms
http://www.soils.org/sssagloss/
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