STATSGO Soils Metadata
DATASET NAME: SP_STATSGO
Identification_Information:
Citation:
Citation_Information:
Originator: Schwarz, G.E. and Alexander, R.B.
Publication_Date: 19950901
Title: State Soil Geographic (STATSGO) Data Base for the
Coternimous United States
Edition: 1.1
Geospatial_Data_Presentation_Form: Series_Name Open-File Report
Issue_Identification 95-449
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Online_Linkage: <http://water.usgs.gov/lookup/getspatial?ussoils
Description:
Abstract: USSOILS is an Arc 7.0 coverage containing hydrology-relevant
information for 10,498 map units covering the entire
conterminous United States. The coverage was compiled
from individual State coverages contained in the October
1994 State Soil Geographic (STATSGO) Data Base produced
on CD-ROM. The geo-dataset USSOILS.PAT relates
(on the basis of a map unit identifier) the 10,498 map
units to 78,518 polygons. The scale of the geo-dataset
is 1:250,000. The INFO attribute table USSOILS.MUID_ATTS
contains selected variables from the STATSGO data set for
10,501 map units (an extra 3 map units are contained in
the attribute table that are not in the geo-dataset -
see the 'Procedures' section below), including: the map
unit identifier, a 2-character state abbreviation,
available water capacity of the soil, percent clay
in the soil, the actual k-factor used in the water
erosion component of the universal soil loss equation,
the organic material in soil, soil permeability,
cumulative thickness of all soil layers, hydrologic
characteristics of the soil, quality of drainage,
surface slope, liquid limit of the soil, share of a
map unit having hydric soils, and the annual frequency
of flooding. To facilitate mapping the attribute data,
the narrative section below contains instructions for
transferring the information contained in the attribute
table USSOILS.MUID_ATTS to the polygon attribute table
USSOILS.PAT. STATSGO United States Soil Water Capacity
Clay Organic material Permeability Infiltration Drainage
Hydric Flood frequency Slope
Purpose: The USSOILS coverage was originally compiled to support
a national model of water quality. The model uses the
soil characteristics contained in this coverage to
mediate deliveries of nonpoint source pollution to
stream and river segments in the RF1 data base. The
National Resource Conservation Service (NRCS)
recommends that any maps using NRCS STATSGO data
show the source and date, and provide the following
statement:
"STATSGO is designed to support regional,
multistate, State, and river basin resource
planning, management and monitoring."
Supplemental_Information:
Procedures_Used: The individual State coverages are from the
State Soil Geographic (STATSGO) CD-ROM data base,
issued by U.S. Department of Agriculture, NRCS
National Cartography and GIS Center, P.O. Box 6567,
Fort Worth, Texas 76115-0567, 1-800-672-5559 (U.S.
Department of Agriculture, 1991). The CD-ROM coverage
for New Mexico was defective and was not used. A
corrected copy of the New Mexico coverage was
obtained from Norman Bliss of the EROS Data Center
((605) 594-6034). The STATSGO State-based coverages
were merged together into a national coverage using
the Arc MAPJOIN command. All nodes along merged
boundaries were checked and edited to remove any
superfluous nodes created during the mapjoin process,
and to ensure arcs properly merged along and across
State boundaries. The joining process preserved
all State boundaries.
To understand the procedures used to create the
attribute table USSOILS.MUID_ATTS, it helps to
have an understanding of the STATSGO data structure.
The smallest spatial entity mapped within the STATSGO
dataset is called a map unit, of which there are
10,498 broken out into 78,518 polygons within the
conterminous United States. Each map unit consists
of up to 21 components. Components are used to
apportion different characteristics of a map unit
and do not represent a separate spatial entity.
To help understand this, consider a map unit that
has only two components. Suppose 30 percent of
this map unit contains soil of type A and the
remaining 70 percent contains soil of type B.
Thus, component 1 of the map unit would have soil
type A and component 2 would have soil type B.
The data base would record the soil type for
each component, along with the percentage of
the map unit represented by each component
(in this example, 30 percent for component 1
and 70 percent for component 2). The specific
locations of soil types A and B are not
spatially defined in the data base.
Each component is further delineated into a
maximum of 6 layers, corresponding to distinct
soil layers. Soil characteristics recorded for a
layer typically consist of a high and low value,
which describes a range for that characteristic
within that layer. Included among the characteristics
of the soil layer is the thickness of the layer.
In developing the USSOILS.MUID_ATTS table,
it is necessary to aggregate the layer and
component information up to the level of a map unit.
To aggregate layer information to the component level,
we first construct a simple average of the high and low
values of a characteristic for each layer. We then
construct a weighted average across all layers of
the layer-specific characteristic averages, the
weights being the thickness of the layer relative
to the total thickness of all layers. For
component-level information that is expressed
as a range, we construct a simple average of
the high and low values defining the range.
These steps reduce layer-specific information
and ranges of component-specific information into
a single datum of component-specific information
for each characteristic in the data base. Finally,
to obtain map unit information, we construct a
weighted average across all components of the
component-specific information, the weights being
the component percentages given for the map unit.
Included in the Notes section below are the
computer programs used to construct the
USSOILS.MUID_ATTS data base, along with an AML
program for transferring this information to
the polygon attribute table USSOILS.PAT. We
ask the reader to refer to the documentation
contained in these programs to obtain detailed
information on the methods used to construct
each data item. The following is a brief
description of how the programs were used.
The AMLs "layer_out.aml" and "comp_out.aml" were
run using the UNIX batch program "batch.prog" to
write data from the STATSGO State INFO layer and comp
files into ascii files. The ascii files were read by
the SAS program "setussoils.sas" to aggregate data from
the layer and component level to the map unit level.
If there is no information available to determine a
characteristic's value in a given map unit, the
characteristic is given the value -0.1 to indicate
a missing value. The program "setussoils.sas" creates
an ascii, comma-delimited file and a SAS file of the
aggregated, map unit data containing information for
10,470 map units. The comma-delimited, ascii file is
then read back into ARC/INFO using the aml
"ussoils_muid_atts.aml" to create the attribute
table USSOILS.MUID_ATTS. Note that there is a
discrepancy between the number of map units contained
in the combined COMP and LAYER files (10,470) and the
number contained in the polygon attribute table (PAT)
USSOILS.PAT (10,498 broken out into 78,518 polygons).
The discrepancy arises because 3 map units in the COMP
and LAYER files were not included in the PAT (these are
- VT029, UTWA1 (not in LAYER file either), and NE165
(not in LAYER file either)), while 31 map units in the
PAT coverage were not in the COMP or LAYER files. The
31 map units missing from the COMP and LAYER files are
all "water" designated map units for which the values
of all items are missing. To assure that the attribute
table is complete, the program 'ussoils_muid_atts.aml'
appends the missing MUIDs from USSOILS.PAT to
USSOILS.MUID_ATTS and sets the attribute values
(except for STATE) to missing. Thus, the total number
of map units contained in USSOILS.MUID_ATTS is 10,501
(10,470 + 31). We made no attempts to correct the
USSOILS.PAT file for the 3 missing map units contained
in the COMP and LAYER files and in the attribute table
USSOILS.MUID_ATTS.
To assist the user in mapping the attribute information,
we include the program 'ussoils_atts.aml' in the "Notes"
section. This program relates the attribute information
for the 10,498 "mapped" map units (10,501 - 3) to the 78,518
polygons contained in the polygon attribute table USSOILS.PAT.
This program may be run as an AML from the command line in ARC
by entering the command: &r ussoils_atts.
Revisions: 1.0 Original Version 1.1 Changed the
documentation and coverages in accordance with comments
received from reviewers. Created the INFO file
USSOILS.MUID_ATTS containing the attribute information
for 10,501 map units. Deleted this information from the
polygon attribute table USSOILS.PAT. Changed the programs
and documentation to reflect this change in file structure.
Reviews_Applied_to_Data: Summary of review by Ken Lanfear, Network Info
Products Coordinator, Reston, VA, August 21, 1995.
Ken reviewed the metadata for the State Soil
Geographic (STATSGO) Data Base for the
Conterminous United States, and the associated
coverage, ussoils.
He viewed the coverage on a computer screen to
ensure arcs were present for the 48 conterminous
States and the District of Columbia (included in
Maryland). He selected several States by Mapping
Unit ID (MUID) and plotted polygons to check that
the states were complete and that mapping units
plotted in the correct state. He also examined the
polygon attribute table, USSOILS.PAT, to note record
counts and verify the format. He spot checked one
mapping unit (TX118) against the original data
(which was on line) and verified that the HYGRP
and DRAIN items were computed correctly.
He read the procedures included under supplementary
information, and concurs with the overall
processing steps. However, time did not permit
him to check details of the coding.
Ken found one possible discrepancy: There are 10,499
(actually 10,498 if we exclude the null map unit
consisting of the "outer" polygon to the coverage)
unique MUID's in the USSOILS.PAT file, but only
10,470 in the SOIL_ATTS file. He inquired where
the 29 extra units came from?
Ken emphasized that the narrative portion should
be modified to make it clear that each mapping unit
can be comprised of several polygons. This caused him
some confusion initially.
Ken had a suggestion for reducing the size of
the coverage. Instead of appending all the items
of SOIL_ATTS to USSOILS.PAT, why not just rename
SOIL_ATTS to USSOILS.SOIL_ATTS ? This file would
export with the coverage. By copying to the .PAT,
the values are repeated an average of about 7.8 times.
However, since the current form of ussoils is large
but workable, he made this suggestion optional.
Summary of review by Barb Ruddy, Hydrologist,
Lakewood, CO, August 31, 1995.
Barb looked at the programs to make sure
they made sense. She found the programs to
be well documented and the procedures to be
appropriate for aggregating the comp and layer
information to a single map unit value. She
checked the values for the variable hygrp and
found they were comparable to the analysis that
she and Bill Battaglin had done. She also looked
at how the data plotted nationally and it checked.
Barb's main concern was the inefficient storage
of the attribute information. Because each map
unit is repeated multiple times in the PAT file,
she suggested that the attribute data could be
more efficiently stored in an info file.
Other_References_Cited: U.S. Department of Agriculture,
National Resource Conservation Service, National
Soil Survey Center, 1991, "State Soil Geographic
(STATSGO) Data Base: Data use information,"
Miscellaneous Publication Number 1492, 110 p.
(Revised July 1994.)
Data_Type: COVER
Software: Arc/INFO 7.2
Operating_System: Windows 2000
Path_Name: \SPDB\Coverages\sp_statsgo
Related_Spatial_Data_Files: All geodatasets with sp_ prefix
References_Cited:
Notes:
Cloud_Cover: N/A
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: Unknown
Currentness_Reference:
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: 532769.000
East_Bounding_Coordinate: 608009.000
North_Bounding_Coordinate: 3466757.500
South_Bounding_Coordinate: 3592762.000
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: State Soil Geographic (STATSGO) Data Base for the
Conterminous United States
Theme_Keyword: San Pedro
Theme_Keyword: STATSGO
Theme_Keyword: watershed
Access_Constraints: None
Use_Constraints: The National Resource Conservation Service recommends that the
data not be used to describe soil characteristics for regions
smaller than a multi-county area.
Data_Provider_Information:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: EPA NERL Las Vegas
Contact_Person: Bill Kepner
Contact_Address:
Address_Type:
Address: P.O. Box 93478
City: Las Vegas
State_or_Province: Nevada
Postal_Code: 89193-3478
Contact_Voice_Telephone: 702 798 2193
Contact_Email_Address: kepner.william@epamail.epa.gov
Data_Processor_Information:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person:
Contact_Address:
Address_Type:
Address:
City:
State_or_Province:
Postal_Code:
Contact_Voice_Telephone:
Contact_Email_Address:
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Gregory E. Schwarz
Contact_Organization: U.S. Geological Survey, Water Resources Div. (WRD)
Contact_Position: Economist, Branch of Systems Analysis
Contact_Address:
Address_Type: mailing address
Address: 12201 Sunrise Valley Drive, MS 410
City: Reston
State_or_Province: VA
Postal_Code: 20191
Country: USA
Contact_Voice_Telephone: 703 648 5718
Contact_Facsimile_Telephone: 703 648 5295
Contact_Electronic_Mail_Address: gschwarz@usgs.gov
Hours_of_Service: 9:00-5:00pm EST
Contact_Instructions: Please contact through email
Data_Set_Credit: See References
Security_Information:
Security_Classification_System: None
Security_Classification: Unclassified
Security_Handling_Description: None
Native_Data_set_Environment: dgux, 5.4R3.10, AViiON UNIX, ARC/INFO 7.0.4
Cross_Reference:
Citation_Information:
Originator: U.S. Dept. of Agriculture, Soil Conservation Service,
National Coop. Soil Survey
Publication_Date: October 1994
Title: State Soil Geographic (STATSGO) Data Base: U.S. Coverage by States
Geospatial_Data_Presentation_Form: map
Other_Citation_Details: ARC/INFO 7.0 coverage on CDROM
Metadata_Reference_Information:
Metadata_Date: 19950918
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Gregory E. Schwarz
Contact_Organization: U.S. Geological Survey, Water Resource Div. (WRD)
Contact_Position: Economist, Branch of Systems Analysis
Contact_Address:
Address_Type: mailing address
Address:12201 Sunrise Valley Drive, MS 410
City: Reston
State_or_Province: VA
Postal_Code: 20191
Country: USA
Contact_Voice_Telephone: 703 648 5718
Contact_Facsimile_Telephone: 703 648 5295
Contact_Electronic_Mail_Address: gshwarz@usgs.gov
Hours_of_Service: 9:00am-5:00pm EST
Contact_Instructions: please contact through email
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: Local time
Metadata_Security_Information:
Metadata_Security_Classification_System: None
Metadata_Security_Classification: Unclassified
Metadata_Security_Handling_Description: None
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report: See Entity_Attribute_Information
Quantitative_Attribute_Accuracy_Assessment:
Attribute_Accuracy_Value: See explanation
Attribute_Accuracy_Explanation: Attribute accuracy is described, where present,
with each attribute defined in the Entity
and Attribute Section.
Logical_Consistency_Report: Polygon topology present
Completeness_Report: Not presently available
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Vertical_Positional_Accuracy: Not presently available
Lineage:
Process_Step:
Process_Description: Reprojected and clipped to SP boundary
Process_Date:
Process_Time:
SPATIAL REFERENCE INFORMATION
Grid Coordinate System: UTM
Horizontal Datum: NAD83
Zone: 12
Units: METERS
Scale:
Precision: SINGLE
SPATIAL DATA ORGANIZATION INFORMATION
Number of Arcs: 246
Annotations: 0
Points: 0
Polygons: 83
Tics: 1343
ENTITY AND ATTRIBUTE INFORMATION
Detailed_Description:
Entity_Type:
Entity_Type_Label: USSOILS.PAT
Entity_Type_Definition: selected items of hydrologic relevance from the
STATSGO Data Base
Entity_Type_Definition_Source: STATSGO Data Base ARC/INFO 7.0 Coverage
CDROM, October 1994
Attibute:
Attribute_Label: -
Attribute_Definition: Selected items of hydrologic relevance from the STATSGO
Data Base
Attribute_Definition_Source: STATSGO Data Base ARC/INFO 7.0 Coverage CDROM
October 1994
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: -
Attribute:
Attribute_Label: AREA
Attribute_Definition: area of poly in square coverage units
Attribute_Definition_Source: Computed
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: positive real numbers
Attribute:
Attribute_Label: PERIMETER
Attribute_Definition: perimeter of polygon in coverage units
Attribute_Definition_Source: Computed
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Positive real numbers
Attribute:
Attribute_Label: USSOILS#
Attribute_Definition: internal feature number
Attribute_Definition_Source: Computed
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Values: sequential unique positive number
Attribute:
Attribute_Label: USSOILS-ID
Attribute_Definition: user-assigned feature number
Attribute_Definition_Source: user-defined
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: integer
Attribute:
Attribute_Label: MUID
Attribute_Definition: Mapunit Identification code - used to reference
observations
Attribute_Definition_Source: STATSGO, October 1994
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: character
Attribute:
Attribute_Label: STATE
Attribute_Definition: 2-character state abbreviation
Attribute_Definition_Source: created from first two characters of muid in STATSGO
data base
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: character
Attribute:
Attribute_Label: AWC
Attribute_Definition: Avaliable water capacity (inches per inch)
Attribute_Definition_Source: Created from AWCH and AWCL in STATSGO (10/94) layer
file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Positive real numbers, missing value indicator=-0.1
Attribute:
Attribute_Label: CLAY
Attribute_Definition: percent clay in soil (percent of material less than
2mm in size)
Attribute_Definition_Source: created from clayh and clayl in STATSGO (10/94)
layer file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0 to 100, missing value indicator = -0.1
Attribute:
Attribute_Label: KFFACT
Attribute_Definition: Actual k factor used in water erosion component of
universal soil loss equation
Attribute_Definition_Source: Created from STATSGO (10/94) component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Non-negative real, missing value indicator = -0.1
Attribute:
Attribute_Label: OM
Attribute_Definition: Organic material in soil (in percent by weight)
Attribute_Definition_Source: Created from omh and oml of STATSGO (10/94)
layer file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0 to 100, missing value indicator = -0.1
Attribute:
Attribute_Label: PERM
Attribute_Definition: Permeability of the soil (in inches per hour)
Attribute_Definition_Source: Created from permh and perml of STATSGO (10/94)
layer file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Non-negative real, missing value indicator = -0.1
Attribute:
Attribute_Label: THICK
Attribute_Definition: Cumulative thickness of all soil layers (in inches)
Attribute_Definition_Source: Created from laydeph and laydepl of STATSGO (10/94)
layer file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Positive real, missing value indicator = -0.1
Attribute:
Attribute_Label: HYGRP
Attribute_Definition: Hydrologic characteristics of soil
Attribute_Definition_Source: Created from hydgrp item of STATSGO (10/94)
component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 1-4:1=High infiltration,2=Mod infil,3=Slow infil,
4=Very slow infil,-0.1=Miss
Attribute:
Attribute_Label: DRAIN
Attribute_Definition: Soil drainage
Attribute_Definition_Source: Created from drainage in STATSGO (10/94)
component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 1-7:1=excess,2=mod excess,3=well,4=mod well,
5=mod poor,6=poor,7=v poor,-.1=miss
Attribute:
Attribute_Label: SLOPE
Attribute_Definition: Surface slope (in percent)
Attribute_Definition_Source: Created from slopeh and slopel of STATSGO (10/94)
component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0 to 100, missing value indicator = -0.1
Attribute:
Attribute_Label: LL
Attribute_Definition: Liquid limit of soil (in percent moisture
by weight)
Attribute_Definition_Source: Created from llh and lll of STATSGO (10/94)
layer file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0 to 100, missing value indicator = -0.1
Attribute:
Attribute_Label: IFHYDRIC
Attribute_Definition: Share of map unit components with hydric soils
Attribute_Definition_Source: Created from hydric of STATSGO (10/94)
component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0 to 1 (1=all components hydric),
missing value indicator = -0.1
Attribute:
Attribute_Label: AFLDFREQ
Attribute_Definition: Annual flood frequency
Attribute_Definition_Source: Created from item anflood of STATSGO (10/94)
component file
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 1-4: 1=greater than 50 pct, 2=5 to 50 pct,
3=0 to 5 pct, 4=none, -0.1=missing
Overview_Description:
Entity_and_Attribute_Overview: The attribute table, USSOILS.MUID_ATTS,
contains the following items for each map unit:
Label Type Description
muid character Map unit identifier
(first two characters are the state abbreviation).
state character 2-character State abbreviation.
awc float Available water capacity (in inches
per inch). Computed as a layer thickness
weighted average, across soil layers, of a
simple average of awch and awcl contained
in the STATSGO layer file.
Missing value .FALSE.
clay float Percent of soil consisting of
clay (in percent of material less than 2mm
in size). Computed as a layer thickness
weighted average, across soil layers, of
a simple average of clayh and clayl
contained in the STATSGO layer file.
Missing value indicator = -0.1.
kffact float Actual k factor used in universal
soil loss equation to calculate soil loss
by water. Computed as a layer thickness
weighted average, across soil layers, of the
variable kffact contained in the STATSGO
layer file. Missing value indicator = -0.1.
ll float Liquid limit of soil layer (in percent
moisture by weight). Computed as a layer
thickness weighted average, across soil layers,
of a simple average of llh and lll contained
in the STATSGO layer file. Missing value
indicator = -0.1.
om float Organic material in the soil (in
percent by weight). Computed as a layer
thickness weighted average, across soil
layers, of a simple average of omh and oml
contained in the STATSGO layer file.
Missing value .FALSE.
perm float Permeability of the soil (in inches
per hour). Computed as a layer thickness
weighted average, across soil layers, of a
simple average of permh and perml contained
in the STATSGO layer file.
Missing value .FALSE.
thick float Depth of soil layers (in inches).
Computed as the sum of the differences between
laydeph and laydepl for each soil layer in
the STATSGO layer file. Missing value .FALSE.
hygrp float A code identifying the hydrologic
characteristics of the soil. The character
codes defined in the STATSGO component file
are converted into numeric codes according
to Bill Battaglin's methods (Battaglin,
written communication dated March 8, 1995).
The coding transformations are A = 1
(high infiltration, deep soils, well
drained to excessively drained sands and
gravels), B = 2 (moderate infiltration rates,
deep and moderately deep, moderately well and
well drained soils with moderately coarse
textures), C = 3 (slow infiltration rates,
soils with layers impeding downward movement
of water, or soils with moderately fine or
fine textures), D = 4 (very slow infiltration
rates, soils are clayey, have a high water
table, or are shallow to an impervious layer),
Mixture codes A/D, B/D, and C/D are assigned
the value 4. Also, we subselect certain areas
and assign values for hygrp based on the area
type. Miscellaneous areas (denoted by M in
compkind) and labeled as Dumps, and Gullied
Land in compname are assigned the hygrp = 2.5
if the hydgrp value is missing. Areas denoted as
Pits, Rock Outcrops, Terrace Escarpments, and
Urban land with missing hydgrp are assigned a
hygrp of 4. See the documentation of the SAS
program "setussoils.sas" for additional details.
The transformed data are averaged across
components using the component percentage as
weights. The missing value indicator is - 0.1.
drain float A code identifying the quality of
soil drainage. The two character code from the
STATSGO component file is converted to a
numeric value according to the following
translation: E = 1 (excessive), SE = 2
(somewhat excessive), W = 3 (well drained),
MW = 4 (moderately drained), SP = 5 (somewhat
poorly drained), P = 6 (poorly drained), and
VP = 7 (very poorly drained). The values are
averaged across components using the component
percentage as weights. The missing value
indicator is -0.1.
slope float The slope of the map unit (in
percent). Slope values contained in the
STATSGO component file are averaged using
the component percentage as weights.
The missing value indicator is -0.1.
ifhydric float Share of map unit with
hydric soils (1 = entire map unit has hydric
soils). Computed by summing the component
percentage for each component designated
as having hydric soils according to the
variable hydric in the STATSGO component
file. Missing value .FALSE.
afldfreq float Annual flood frequency code.
Flood frequency designations contained in the
variable anflood in the STATSGO component file
are converted to numeric codes according to the
following translation: 1 = greater than 50%,
2 = 5% to 50%, 3 = 0% to 5%, and 4 = no flood.
Translated variables are averaged across
components using the component percentage
as weights. The missing value indicator is -0.1.
Entity_and_Attribute_Detail_Citation: not available
ATTRIBUTE LISTING FOR:
| COLUMN |
ITEM NAME |
WIDTH |
OUTPUT |
TYPE |
N. DEC |
ALTERNATE NAME |
INDEXED? |
| 1 |
AREA |
4 |
12 |
F |
|
| |
|
- |
| 5 |
PERIMETER |
4 |
12 |
F |
|
| |
|
- |
| 9 |
SP_STATSGO# |
4 |
5 |
B |
- |
|
- |
| 13 |
SP_STATSGO-ID |
4 |
5 |
B |
- |
|
- |
| 17 |
MUID |
7 |
7 |
C |
- |
|
- |
| ** |
REDEFINED |
ITEMS |
** |
|
|
|
|
| 19 |
IDS |
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