Conversion of Alabama 2004
Frequently-anticipated questions:
What does this data set describe?
- Title: Conversion of Alabama 2004
- Abstract:
- The United States Department of Agriculture (USDA), National
Agricultural Statistics Service (NASS) area sampling frame is a
delineation of all parcels of land for the purpose of later sampling the
parcels. The area frame is constructed by visually interpreting satellite
imagery to divide a state into homogenous land use areas (strata) based
on percent cultivated. The strata are typically defined as low, medium or
high percent cultivated, non-agricultural land, urban use, agri-urban, or
water. The boundaries of the strata usually follow identifiable features
such as roads, railroads and waterways. The strata boundaries do not
coincide with any political boundaries, with the exception of state
boundaries.
Though all of the dates for this frame point to 2004, this is only when the
older frame from the paper map was converted over to digital form. All of the
stratification work for the paper maps and was completed in 1990.
- Supplemental_Information: N/A
How should this data set be cited?
United States Department of Agr, National Agricultural Statistics Service, 2004, Conversion of Alabama 2004: U.S. Department of Agriculture, National Agricultural Statistics Service, Fairfax, Virginia.
Online Links:
What geographic area does the data set cover?
- West_Bounding_Coordinate: -88.47
- East_Bounding_Coordinate: -84.89
- North_Bounding_Coordinate: 35.00
- South_Bounding_Coordinate: 30.22
What does it look like?
Does the data set describe conditions during a particular time period?
- Calendar_Date: 2003
- Currentness_Reference: N/A
What is the general form of this data set?
How does the data set represent geographic features?
How are geographic features stored in the data set?
- Indirect_Spatial_Reference:
- U.S. Department of Commerce, 1990, Counties and Equivalent
Entities of The United States, Its Possessions, and
Associated Areas (Federal Information Processing Standard
6-4): Washington, D.C. National Institute of Standards and
Technology.
This is a Vector data set.
It contains the following vector data types (SDTS terminology):
What coordinate system is used to represent geographic features?
- Grid_Coordinate_System_Name: Universal Transverse Mercator
- Universal_Transverse_Mercator:
-
- UTM_Zone_Number: 16
- Transverse_Mercator:
-
- Scale_Factor_at_Central_Meridian: 0.9996
- Longitude_of_Central_Meridian: -99.00
- Latitude_of_Projection_Origin: 0.0
- False_Easting: 500000.00
- False_Northing: 0.0
Planar coordinates are encoded using row and column
Abscissae (x-coordinates) are specified to the nearest 30
Ordinates (y-coordinates) are specified to the nearest 30
Planar coordinates are specified in Meters
The horizontal datum used is North American Datum of 1983.
The ellipsoid used is Geodetic Reference 80.
The semi-major axis of the ellipsoid used is 6378137.00.
The flattening of the ellipsoid used is 1/298.257.
How does the data set describe geographic features?
- Land Use Strata
- Homogeneous land use area based on percent cultivated
(Source: U.S. Department of Agriculture, National Agricultural Statistics Service)
- Strata
- Land use category based on percent cultivated
(Source: U.S. Department of Agriculture, National Agricultural Statistics Service)
Land USe Based on Percent Cultivated
Value |
Definition |
13 |
50% CULTIVATED
|
20 |
15-50% CULTIVATED |
31 |
AGRI-URBAN, MORE THAN 20 DWELLINGS PER SQ. MILE |
32 |
RESIDENTIAL-COMMERCIAL, > 20 DWELLINGS PER SQ. MILE |
40 |
< 15% CULTIVATED |
50 |
NON AGRICULTURAL |
- Sum_area
- The stratum area in square miles.
(Source: U.S. Department of Agriculture, National Agricultural Statistics Service)
Stratum Area in Square Miles
Range of values |
Minimum: |
105.83 (actual value, not range) |
Maximum: |
35,361.18 |
- Sum_acres
- The amount of acres in a stratum.
(Source: U.S. Department of Agriculture, National Agricultural Statistics Service)
Number of Acres in Stratum
Range of values |
Minimum: |
67,731.13 (actual value, not range) |
Maximum: |
22,631,158.16 (actual value, not range) |
Who produced the data set?
- Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
- United States Department of Agriculture, National Agricultural
- Who also contributed to the data set?
Area Frame Section staff
- To whom should users address questions about the data?
USDA/NASS
1400 Independence Ave. SW
Washington, D.C. 20250
Customer Service: 1-800-727-9540
Why was the data set created?
These data are intended for geographic display and analysis at the state
level. The data should be displayed and analyzed at a scale of
1:100,000 or smaller (e.g., 1:250,000, etc.). The strata data are
provided "as is". USDA/NASS does not warrant results you may obtain
using the strata data.
How was the data set created?
- From what previous works were the data drawn?
- TopoDRG100
(source 1 of 6)
U.S. Geologic Survey (USGS), 1979 - 1991, USGS Topographic Quadrangles: U.S. Geologic Survey, Reston, VA.
- Type_of_Source_Media: On-line
- Source_Scale_Denominator: 100000
- Source_Contribution: Spatial and attribute information
- NAPP
(source 2 of 6)
Agency, Farm Service , 1999, National Aerial Photography Program (NAPP): Aerial Photography Field Office (APFO), Salt Lake City, UT.
- Type_of_Source_Media: CD-Rom
- Source_Scale_Denominator: 40000
- Source_Contribution: Spatial and attribute information
- TopoDRG24
(source 3 of 6)
U.S. Geological Survey (USGS), 1979 - 1991, USGS Topographic Quadrangles: U.S. Geological Survey, Reston, VA.
- Type_of_Source_Media: On-line
- Source_Scale_Denominator: 24000
- Source_Contribution: Spatial and attribute information
- TIGER
(source 4 of 6)
United States Census Bureau, 2000, TIGER Digital Vector Files: U.S. Census Bureau, Suitland, MD.
- Type_of_Source_Media: CD-Rom
- Source_Contribution: Spatial and attribute information
- TM5
(source 5 of 6)
NASA, 1987 & 1986, Landsat 5 Thematic Mapper Imagery: Space Imaging, Lanham, MD.
- Type_of_Source_Media: Paper
- Source_Scale_Denominator: 250000
- Source_Contribution: Spatial and attribute information
- AFSPaper
(source 6 of 6)
National Agricultural Statistics Service, 2003, Area Frame Design for Agricultural Surveys: NASS/USDA, Washington, DC.
- Type_of_Source_Media: Paper
- Source_Contribution: Spatial and attribute information
- How were the data generated, processed, and modified?
- Date: 2003 (process 1 of 1)
- The area sampling frame for Alabama was constructed for use in 2004
and was based on USGS 1:24,000 and 1:100,000 scale topographic maps,
1:250,000 scale Landsat imagery, and 2 meter resolution NAPP imagery.
Individual county files were merged into single statefile. The coordinates
for the strata polygons are unprojected to geographic latitude and longitude
(decimal degrees). The spatial data file format is Environmental Systems
Research Institute's ArcView shapefile format. Gaps and overlaps were corrected
within and ESRI personal geodatabase.
Though all of the dates for this frame point to 2004, this is only when the
older frame from the paper map was converted over to digital form. All of the
stratification work for the paper maps and was completed in 1990.
Data sources used in this process:
- TopoDRG100
- NAPP
- TopoDRG24
- TIGER
- TM5
- AFSPaper
- What similar or related data should the user be aware of?
How reliable are the data; what problems remain in the data set?
- How well have the observations been checked?
- How accurate are the geographic locations?
The sources used for digitizing strata boundaries are 1:100,000 scale
Digital Raster Graphics
- How accurate are the heights or depths?
- Where are the gaps in the data? What is missing?
There are known gaps and overlaps. This data set includes the area in
square miles and number of acres for each strata. Boundaries may not be
coincident with strata boundaries of adjacent states.
- How consistent are the relationships among the observations, including topology?
Checks for topological consistency were performed on this data set.
How can someone get a copy of the data set?
Are there legal restrictions on access or use of the data?
- Access_Constraints: None
- Use_Constraints:
- None. Acknowledgment of the U.S. Department of Agriculture, National
Agricultural Statistics Service would be appreciated in products derived
from these data.
- Who distributes the data set?
(Distributor 1 of 1)
USDA/NASS/RDD
1400 Independence Ave SW
Washington, D.C. 20250
- Contact_Instructions: N/A
- What's the catalog number I need to order this data set?
- What legal disclaimers am I supposed to read?
Users of the strata data are solely responsible for interpretations made
from the product. The strata data are provided "as is". USDA/NASS does
not warrant results you may obtain by using the strata data. Feel free to
contact our staff at (HQ_RD_OD@nass.usda.gov) if technical questions arise
in the use of the strata data.
- How can I download or order the data?
- Availability in digital form:
- Cost to order the data: There is no charge for the online option.
- Special instructions:
N/A
Who wrote the metadata?
- Dates:
- Last modified: 16-Jan-2014
- Metadata author:
USDA/NASS/RDD
1400 Independence Ave. SW
Washington, D.C. 20250
- Metadata standard:
- FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Generated by mp version 2.7.33 on Thu May 14 16:51:33 2015