Identification_Information:
Citation:
Citation_Information:
Originator: USDA Forest Service - Geospatial Service and Technology Center (GSTC)
Publication_Date: 20000915
Title: National Inventoried Roadless Areas (IRAs)
Edition: Final
Geospatial_Data_Presentation_Form: ArcInfo export
Publication_Information:
Publication_Place: Salt Lake City, UT
Publisher: USDA Forest Service - GSTC
Description:
Abstract:
This dataset contains all National Forest Inventoried Roadless Areas (IRAs) for the lower 48 states, including Puerto Rico. Alaska is maintained separately. The IRA data was originally submitted to GSTC by all national forests through their Regional Offices for the Forest Service’s Roadless Area Conservation Initiative.
The data was consolidated at the GSTC and used in the Draft Environment Impact Statement. Between the draft and final stages of the Environmental Impact Statement, the data was updated by the forests to reflect any corrections to Inventoried Roadless Areas that were based on their existing forest plan. The data was also supplemented to include Special Designated Area information and to include Inventoried Roadless Areas within Special Designated Areas. The data was resubmitted to the GSTC on July 21, 2000 for consolidation and the completed coverage was used in the Roadless Area Conservation Final Environmental Impact Statement.
IRAs are based on completed forest plans, forest plans in revision where the agency has established an inventory (this information should be available in Appendix C of most forest plans), or other assessments that are completed and adopted by the agency. RARE II information was used in cases where a forest does not have a more current roadless inventory, which was established using RARE II information.
Purpose:
The purpose of this spatial data set is to show where the Inventoried Roadless Areas are located. The EIS analysis team used this spatial data to assess the impacts of roadless area alternatives on Forest Service policies, use of the National Forests and the surrounding environment. It was used for analysis in combination with national characterization layers, such as ambient human population, forest mortality risk to insects and diseases, current land cover types, and others. All of these datasets include the entire lower 48 states, and are coarse resolution. The public also had a need to know where IRAs were located in their area and across the nation. The data was used to create a set of detailed maps published both on the web and in hardcopy form, (Volume2, Roadless Area Conservation EIS).
Supplemental_Information:
All of the following editing processes were performed using ARC/INFO software.
The IRA data was originally submitted to GSTC on December 3, 1999 for the Draft Environmental Impact Statement. The data was submitted in ARC/INFO export format (.e00), in most cases as individual national forest coverages, but in some cases together with other national forests. The original datasets submitted were derived from a variety of original source manuscripts, most IRA data had a scale of 1:24,000. Some datasets were of smaller scale, typically 1:126,720. Each national forest was originally compiled at a different time, from different source material, using various methods. Region 5 submitted one file, which included all national forests in that region (primarily the state of California). In these instances, individual coverages were extracted by national forest administrative unit, and edited separately. All data was imported, projected to Albers and audited to check for INFO item consistency. Unnecessary features were removed and label errors removed.
Each national forest dataset was spatially edgematched to a national forest boundary dataset compiled at GSTC for this purpose, and attribute information was added or corrected. It was GSTC's intent to change the original data as little as possible, altering the geometry only as necessary to fit the National Forest Boundary coverage, and editing attributes only for consistency or where apparent errors occurred.
Edgematched data to National Forest Boundary coverage by –
1) intersected the IRA and the NF boundary coverages using the UNION command with a fuzzy tolerance of 1.5 map units (meters)
2) deleted polygons that extended beyond NF boundary as long as they appeared to be sliver polygons created by union
3) deleted/absorbed polygons that did not extend to NF boundary by eliminating all interior polygons less than 5 acres in size that had no IRA category value or NF ownership status using ELIMINATE command
4) merged remaining polygon undershoots using the MERGE command via manual editing
5) conducted final quality assessment to check all work - this consisted of running acreage calculations for polygons before and after the edgematching process; all differences of 100 acres or greater were checked on screen and corrected if necessary; acreage calculations were run again after corrections were made to ensure there were no major changes (in some cases, changes were necessary after verifying with forest personnel that an error in the original data existed); a query was run on all coverages which resulted in a report showing frequency of polygons that had no ownership item and no IRA category - these were checked visually using hard copy maps and phone calls to forests, if necessary, to verify what the polygons in question were; all IRA coverages were also checked visually on the screen to make sure there were no additional errors.
Regional coverages were created by first appending the completed individual national forest IRA coverages into administrative regional coverages, using the APPEND command with the polygon option. This resulted in seven regional coverages for Regions: 1 (Northern), 2 (Rocky Mountain), 3 (Southwestern), 4 (Intermountain), 5 (Pacific Southwest), 6 (Pacific Northwest), 8 (Southern), and 9 (Eastern). These seven regional coverages were then appended into the national coverage, again, using the APPEND command.
The resulting national coverage was automatically edited, using the CLEAN command, with a fuzzy tolerance of 1.5 meters. This removed geometric errors, and rebuilt topology. The coverage was then reprojected from Albers to decimal degrees for consistency with all other coverages used for analysis work.
Between the draft and final stages of the Environmental Impact Statement, the data was updated by the forests to reflect any corrections to Inventoried Roadless Areas that were based on their existing forest plan. The data was also updated to include Special Designated Area information and to include Inventoried Roadless Areas within Special Designated Areas. After these updates were made the data was resubmitted to the GSTC on July 21, 2000 for consolidation.
The final consolidation of the national IRA coverage was accomplished at the GSTC with the benefit of having one representative from each region to assist with quality control. All the completed regions were appended together into the national coverage and reprojected from Albers to decimal degrees for analysis and display in the Roadless Area Conservation Environmental Impact Statement. The IRAs only were selected from national coverage to make this dataset.
***** Spatial Reference Information (Beg) *****
Projection Parameters: Decimal Degrees
NAD27
Spatial Information: Vector
Scale of original/hardcopy map: 1:24,000 to 1:198,000
Feature Type: Polygon
Attributes:
|
ITEM NAME |
WIDTH |
OUTPUT |
TYPE |
DECIMAL |
|
AREA |
8 |
18 |
F |
5 |
|
PERIMETER |
8 |
18 |
F |
5 |
|
IRA_USA# |
4 |
5 |
B |
|
|
IRA_USA-ID |
4 |
5 |
B |
|
|
REGION |
2 |
2 |
I |
|
|
FOREST |
40 |
40 |
C |
|
|
STATE |
2 |
2 |
C |
|
|
NAME |
80 |
80 |
C |
|
|
CATEGORY |
4 |
4 |
C |
|
|
ACRES |
16 |
16 |
N |
5 |
Definitions:
CATEGORY
1B = Inventoried Roadless Areas where road construction and reconstruction is prohibited.
1B-1 = Inventoried Roadless Areas that are recommended for wilderness designation in the forest plan and where road construction and reconstruction is prohibited.
1C = Inventoried Roadless Areas where road construction and reconstruction is not prohibited.
***** Spatial Reference Information (End) *****
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19991203
Ending_Date: 20000915
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Unknown
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -124.5
East_Bounding_Coordinate: -65.5
North_Bounding_Coordinate: 49
South_Bounding_Coordinate: 18
Keywords:
Theme:
Theme_Keyword_Thesaurus: NA
Theme_Keyword: national inventoried roadless areas
Place:
Place_Keyword_Thesaurus: NA
Place_Keyword: national forests
Temporal:
Temporal_Keyword_Thesaurus: NA
Temporal_Keyword: NA
Access_Constraints:
User needs to exercise caution regarding the spatial accuracy of these data. The source scales can vary. External features cannot be expected to align. The National Forest Planning Record Documents (Appendix C), other assessments adopted by the USDA Forest Service, or RARE II documents, are ultimately the official version of inventoried roadless areas.
Use_Constraints:
Data may be viewed and used by any and all entities upon request. However, data should not be changed or modified by anyone other than GSTC. The USDA Forest Service does not guarantee the accuracy of this data.
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Dan Thompson
Contact_Organization: USDA Forest Service - GSTC
Contact_Address:
Address_Type: Mailing and Physical Address
Address: 2222 West 2300 South
City: Salt Lake City
State_or_Province: UT
Postal_Code: 84119
Contact_Voice_Telephone: (801) 975-3441
Contact_Facsimile_Telephone: (801) 975-3478
Contact_Electronic_Mail_Address: dthompson01@fs.fed.us
Distribution_Liability:
The USDA Forest Service manages resource information and derived data as a service to USDA Forest Service users of digital geographic data. The USDA Forest Service is in no way condoning or endorsing the application of these data for any given purpose. It is the sole responsibility of the user to determine whether or not the data are suitable for the intended purpose. It is also the obligation of the user to apply those data in an appropriate and conscientious manner. The USDA Forest Service provides no warranty, nor accepts any liability occurring from any incorrect, incomplete, or misleading data, or from any incorrect, incomplete, or misleading use of these data.
Much of the USDA Forest Service data are compiled, processed, and maintained with ARC/INFO software developed by the Environmental Systems Research Institute (ESRI). Much of the information presented uses conventions and terms popularized by ARC/INFO and its user community. The mention of commercial firms or products is for clarity and identification of procedures and methods only, and no endorsements are implied by the USDA Forest Service.
Metadata_Reference_Information:
Metadata_Date:
Metadata_Contact:
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998