Soil and Vegetation Survey of the Gulkana River Area, Alaska - Soils Part - Line Segment Data

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Mark Clark

Publication_Date: 1999

Title:

Soil and Vegetation Survey of the Gulkana River Area, Alaska - Soils Part - Line Segment Data

Geospatial_Data_Presentation_Form: Map

Publication_Information:

Publication_Place: Wasilla, Alaska

Publisher: USDA - Natural Resources Conservation Service

Description:

Purpose:

These data depict information about the kinds and distribution of soils on the landscape. The soil map and data used in this product were prepared by soil scientists and plant ecologists as part of the National Cooperative Soil Survey.

Abstract:

This data set is a digital soil survey made at a detailed level (order two) as defined by the National Cooperative Soil Survey. Inventory objectives and procedures were developed by the Natural Resources Conservation Service (NRCS) in conjunction with potential users within the Bureau of Land Management (BLM). Color infrared aerial photography, dated July 1989, and orthophoto quads covering the entire survey area were provided by the BLM at a nominal scale of 1:24,000 and prepared for field use and mapping. Two levels of mapping intensity were used for the soils maps. The complex of flood plains and stream terraces immediately adjacent to the river channel, which receives the highest intensity of recreational use and provides the most productive and diverse wildlife habitat, was of greatest concern and interest to BLM biologists and land managers. Within this area, minimum polygon size is about 10 acres. Important riparian areas that were in general too narrow to delineate with polygons are shown as labeled line segments. Approximately 85 percent of the delineations were visited during field work. Delineation boundaries were located from field observation and stereoscopic photo-interpretation. Approximately 22,000 acres (24 percent of the survey area) was mapped at this higher level of intensity.

The remaining 71,000 acres (76 percent of the area) of uplands, where the intensity of land use and quality of wildlife habitat are generally lower, were mapped at a lower level of intensity. In these areas, between 6 and 7 representative delineations of each map unit were visited in the field to determine general characteristics. Polygon boundaries were located using a combination of stereoscopic photo-interpretation and established landform, and soil and vegetation relations. Average polygon size in the uplands is substantially larger and line segments were used on infrequent occasions only. Soils field data were collected by transecting tentative soil map units and making observations at predetermined intervals. All transect and stop locations were plotted on the aerial photographs and USGS 1:63,360 topographic maps for permanent record and later reference during map preparation and data analysis.

Field data were entered into the Alaska Soil Survey Field Database (SSFDD) for data management and analysis. Results of data analysis were entered into the standard NRCS Map Unit Interpretation Record (MUIR) database, which gives the proportional extent of the component soils and their properties.

Information from soil field sheets were transferred to mylar overlays on the orthophotography. Then, overlays were scanned, digitized, and georeferenced. Preliminary digital data files were then checked against each corresponding orthophoto for adequate line placement and adjusted where necessary. Finally, soil polygons were attributed.

Supplemental_Information:

Three additional digital map sets were developed in conjunction with the Soil and Vegetation Survey of the Gulkana River, Alaska. Other layers are subtitled "Soils Part - Polygon Data," "Vegetation Part - Polygon Data," and "Vegetation Part - Line Segment Data." A detailed written report and printed map sheets was produced as part of the survey. Written documentation includes descriptions of ecological unit, soil, and vegetation map units; descriptions of the soil taxonomic units and vegetation cover types; and a detailed description of field and office procedures used during the survey. Interpretations for use and management of the area for recreation and wild life habitat are included also.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 1992

Ending_Date: 1995

Currentness_Reference: Field Work Completed

Status:

Progress: Complete

Maintenance_and_Update_Frequency: None Planned

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -143.7409

East_Bounding_Coordinate: -141.110

North_Bounding_Coordinate: 62.9797

South_Bounding_Coordinate: 62.5199

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: Soil Survey

Theme_Keyword: Soils

Theme_Keyword: Geomorphology

Place:

Place_Keyword_Thesaurus: None

Place_Keyword: Gulkana River

Place_Keyword: Gulkana Quadrangle

Place_Keyword: Alaska

Access_Constraints: NONE

Use_Constraints:

United States Department of Agriculture, Natural Resources Conservation Service, should be acknowledged as the data source in products derived from this data. This data set is not designed for use as a primary regulatory tool in permitting or citing decisions, but may be used as a reference source. The data is public information and may be interpreted by organizations, agencies, units of government, or others based on needs; however, they are responsible for the appropriate application. Federal, State, or local regulatory bodies are not to reassign to the Natural Resources Conservation Service any authority for the decisions that they make. The Natural Resources Conservation Service will not perform any evaluations of these maps for purposes related solely to State or local regulatory programs. Photographic or digital enlargement of these maps to scales greater than the original mapping can cause misinterpretation of the data. If enlarged, maps do not show the small areas of contrasting vegetation that could have been shown at a larger scale. The depicted map unit boundaries, map unit descriptions, and interpretations do not eliminate the need for onsite sampling, testing, and detailed study of specific sites for intensive uses. Thus, these data and their interpretations are intended for planning purposes only.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:

United States Department of Agriculture, Natural Resources Conservation Service

Contact_Person: Mark Clark

Contact_Position: Soil Scientist

Contact_Address:

Address_Type: mailing and physical address

Address: 351 W. Parks Hwy, Suite 200

City: Wasilla

State_or_Province: AK

Postal_Code: 99654

Country: USA

Contact_Voice_Telephone: 907-373-6491

Contact_Facsimile_Telephone: 907-373-7192

Contact_Electronic_Mail_Address: mark.clark@ak.usda.gov

Hours_of_Service: 8 am - 5 pm AST

Native_Data_Set_Environment: Arc/Info

 

 

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Digital maps were tested by manual comparison of the source with hard copy plots. In addition, the attributes are tested against a master set of valid attributes. All attribute data conform to the attribute codes in the written manuscript.

Logical_Consistency_Report:

All internal polygons are tested for closure with vendor software and were checked against hard copy plots.

Completeness_Report:

A map unit is a collection of areas defined and named the same in terms of their soil and/or miscellaneous land type. Each map unit differs in some respect from all others and is uniquely identified. Each individual area is a delineation. Each map unit consists of one or more components.

Miscellaneous land types are non-soil areas such as rock outcrops or barren alluvium that have properties and behavior significantly different than the named soil or vegetation in the surrounding map unit. These components are not indicated on the map, however, are described within the appropriated map unit description.

Specific National Cooperative Soil Survey standards and procedures were used in the classification of soils, design and name of map units. These standards are outlined in Agricultural Handbook 18, Soil Survey Manual, 1993, USDA, SCS; Agricultural Handbook 436, Soil Taxonomy, Soil Survey Staff, 1975, USDA, SCS; and all Amendments; Keys to Soil Taxonomy, Soil Survey Staff, (current issue); National Soil Survey Handbook, title 430-VI, 1997.

Map unit composition were based on field data collected by soil scientists and plant ecologists. Adherence to National Cooperative Soil Survey standards and procedures is based on peer review, quality control, and quality assurance. Quality control is outlined in the memorandum of understanding for the soil survey area and in documents that reside with the Natural Resources Conservation Service state soil scientist. Four kinds of map units are used in soil surveys: consociation, complexes, associations, and undifferentiated groups.

Consociations - Consociations are named for the dominant soil. In a consociation, delineated areas are dominated by a single soil taxon and similar soils. At least one half of the pedons in each delineation are of the same soil component or so similar to the named soil that major interpretations are not affected significantly. The total amount of dissimilar soils with soil properties that interpret differently than the named soil component generally does not exceed about 15 percent (referred to as inclusions) and a single kind of dissimilar soil usually does not exceed 10 percent.

Complexes and associations - Complexes and associations are named for two or more dissimilar components with the dominant component listed first. They occur in a regularly repeating pattern. The major components of a complex cannot be mapped separately at a scale of about 1:24,000. The major components of an association can be separated at a scale of about 1:24,000, however, intended land use described in the memorandum of understanding does not warrant delineating each component. In each delineation of either a complex or an association, each major component is normally present, though their proportions may vary appreciably from one delineation to another. the total amount of dissimilar soils with soil properties that interpret differently than the named soil components generally does not exceed 15 percent and a single kind of dissimilar soil usually does not exceed 10 percent.

Undifferentiated groups - Undifferentiated groups consist of two or more components that do not always occur together in the same delineation, but are included in the same named map unit because use and management are similar for common uses. Every delineation has at least one of the major components and some may have all of them. The same principles regarding proportion of inclusions apply to undifferentiated groups as to consociations.

Minimum documentation consists of ten complete soil profile descriptions of each commonly occurring soil component and five complete soil profile descriptions of less extensive soil components in the legend. Documentation of map unit composition included a minimum of six transects per map unit with each transect consisting of one to ten observations. Overall, approximately 85 percent of delineations were visited along valley bottoms and six to seven representative delineations of each map unit visited in the uplands above the various river valleys.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

The accuracy of these digital data is based upon their compilation to base maps that meet National Map Accuracy Standards. The difference in positional accuracy between the soil boundaries in the field and their digitized map locations is unknown. The locational accuracy of soil delineations on the ground varies with the transition between map units.

For example, on long gently sloping landscapes the transition between soils occurs gradually over many feet. Where landscapes change abruptly from steep to level, the transition will be very narrow. Soil delineation boundaries generally were digitized within 0.05 inch of their location on the digitized source. The digital map is provided as a single continuous coverage of the project area and as individual map sheets for printing purposes.
 
 

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report: unknown

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator: BLM

Title: Various Orthophoto Enlargements of the Gulkana River Corridor.

Publication_Date: 1986

Source_Contribution: Base maps used to compile field linework.

Source_Scale_Denominator: 24000

Type_of_Source_Media: Mylar

Source_Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: 1986

Source_Currentness_Reference: none

Source_Citation_Abbreviation: ORTHOS

Process_Step:

Process_Description:

Manual rubbersheeting of field work to a rectified base orthophotobase

Source_Used_Citation_Abbreviation: RBB

Process_Date: 1998

Process_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Organization: USDA/NRCS

Contact_Person: Ted Cox

Contact_Address:

Address_Type: mailing and physical address

Address: 351 W. Parks Hwy.

City: Wasilla

State_or_Province: Alaska

Postal_Code: 99654

Country: USA

Contact_Voice_Telephone: 907 373 6493

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Vector

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: Piecewise Bezier

Point_and_Vector_Object_Count: 165

 

 

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Map_Projection:

Map_Projection_Name: Albers Conical Equal Area

Albers_Conical_Equal_Area:

Longitude_of_Central_Meridian: -154

Latitude_of_Projection_Origin: 50.000

Standard_Parallel: 55

False_Easting: 0.00000

False_Northing: 0.00000

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: Coordinate pair

Coordinate_Representation:

Abscissa_Resolution: .61

Ordinate_Resolution: .61

Planar_Distance_Units: METERS

Geodetic_Model:

Horizontal_Datum_Name: North American Datum 1927

Ellipsoid_Name: CLARKE1866

Semi-major_Axis: 6378206.4

Denominator_of_Flattening_Ratio: 294.98

 

 

Entity_and_Attribute_Information:

Overview_Description:

Entity_and_Attribute_Overview:

Soil map unit delineations are closed polygons or line segments. A soil map unit may be dominated by a single soil component or by a mixture of up to three soil components, plus allowable similar and dissimilar soils. A map unit symbol uniquely identifies each polygon or line segment. The map unit symbol provides a link to the map unit name and to selected attribute information. Attribute data, which are derived from the National Soils Information System database, are described below.

Table - ecolsubsec.txt 
Position,Column,Description 
1,SubID,Subsection identification code (links to soil.txt) 
2,SubName,Subsection name 
3,SubLandf,Major landforms 
4,SubGeoMat,Predominant surface geological materials 
5,SubGeoPedo,Principal geomorphic and pedologic processes 
6,SubVeg,Characteristic vegetation 
7,SubClimate,Subregional climate

Table - ecollta.txt 
Position,Column,Description 
1,SubID,Subsection identification code (links to soil.txt) 
2,LtaID,Landtype Association identification code (links to soil.txt) 
3,LtaName,Landtype Association name 
4,LtaElevL,Elevation in feet; lower limit 
5,LtaElevU,Elevation in feet; upper limit 
6,LtaLandf,Major landforms 
7,LtaGeoMat,Predominant surface geologic materials 
8,LtaGeoPedo,Principal geomorphic and pedologic processes 
9,LtaVeg,Characteristic vegetation 
10,LtaPptL,Annual precipitation in inches; lower limit 
11,LtaPptU,Annual precipitation in inches; upper limit 
12,LtaGradL,Nominal stream gradient; lower limit (SubCode=135A1 only) 
13,LtaGradU,Nominal stream gradient; upper limit (Subcode=135A1 only)

Table - soil.txt 
Position,Column,Description 
1,Soil-id,Unique polygon ID; ArcInfo internal record; polygon data set 
2,Soil_code,Soil map unit publication symbol (links to soilcomp.txt and soilrec.txt) 
3,SubID,Subsection level of Ecoregion classification (links to ecolsubsec.txt and ecollta.txt)) 
4,LtaID,Landtype Association level of Ecoregion classification (links to ecollta.txt) 
5,SoiAcres,Soil polygon acres

Table - soilrip.txt 
Position,Column,Description 
1,Soilrip-id,Line segment ID; ArcInfo internal record; line segment data set 
2,Soil_code,Soil map unit publication symbol (links to soilcomp.txt and soilrec.txt)

Table - soilcomp.txt 
Position(s),Column(s),Description 
1,Soil_code,Soil map unit publication symbol (links to soil.txt and soilrip.txt
2,SoiMuname,Soil map unit name 
3,SoiElevL,Elevation in feet; approximate lower limit 
4,SoiElevU,Elevation in feet; approximate upper limit 
5|35|65,SoiCoName1-3,Soil map unit component name 
6|36|66,SoiCoPct1-3,Representative percent composition of component in map unit 
7|37|67,SlopeMin1-3,Slope gradient in percent; lower limit 
8|38|68,SlopeMax1-3,Slope gradient in percent; upper limit 
9|39|69,Texture1-3,USDA texture of the surface soil layer 
10|40|70,FloodFreq1-3,Annual flooding frequency (NONE; RARE; OCCASional; FREQuent) 11|41|71,FloodDur1-3,Flooding duration (BRIEF; LONG) 
12|42|72,FloodBeg1-3,Earliest month when flooding is expected 
13|43|73,FloodEnd1-3,Latest month when flooding is expected 
14|44|74,WaterMin1-3,Depth in feet to top of water table; upper limit (6 indicates no water table present within 6 feet of soil surface) 
15|45|75,WaterMax1-3,Depth in feet to top of water table; lower limit (6 indicates no water table present within 6 feet of soil surface) 
16|46|76,WaterType1-3,Water table type (APPARent; PERCHed) 
17|47|77,WaterBeg1-3,Beginning month of peak water table 
18|48|78,WaterEnd1-3,Ending month of peak water table 
19|49|79,PondMin1-3,Depth in feet of surface ponding; minimum depth 
20|50|80,PondMax1-3,Depth in feet of surface ponding; maximum depth 
21|51|81,PondDur1-3,Relative duration of surface ponding (LONG) 
22|52|82,PondBeg1-3,Earliest month when ponding is expected 
23|53|83,PondEnd1-3,Latest month when ponding is expected 
24|54|84,RockMin1-3,Depth in inches to bedrock; minimum (60 indicates bedrock is greater than 60 inches below soil surface) 
25|55|85,RockMax1-3,Depth in inches to bedrock; maximum (60 indicates bedrock is greater than 60 inches below soil surface) 
26|56|86,RockHard1-3,Bedrock hardness; HARD 
27|57|87,SubsidIn,Initial subsidence in inches expected within 3 years following fire or other disturbance 
28|58|88,SubsidTot1-3,Total subsidence in inches expected after 3 years following fires or other disturbance 
29|50|89,Frost1-3,Hazard of frost action (LOW; MODERATE; HIGH) 30|60|90,Drainage1-3,Soil drainage class ((V)ery (P)oorly; (P)oorly; (S)omewhat (P)oorly; (M)oderately (W)ell; (W)ell; (S)omewhat (E)xcessively) 
31|61|91,Hydric1-3,Hydric soil status ((Y)es; (N)o; (U)ndetermined) 
32|62|92,Perma1-3,Permafrost status within 60 inches below soil surface ((Y)es; (N)o; (U)ndetermined) 
33|63|93,EcoSite1-3,Ecological site name 34|64|94,EcoPnc1-3,Baseline (potential natural) plant community correlated to the ecological site

Table - soilrec.txt 
Position(s),Column(s),Description 
1,Soil_code,Soil map unit publication symbol (links to soil.txt and soilrip.txt) 
2|3|4,ATV1-3,Interpretation rating for all terrain vehicles (Slight; Moderate; Severe) 
5|6|7,Camp1-3,Interpretation rating for primitive camp areas (Slight; Moderate; Severe) 
8|9|10,Path1-3,Interpretation rating for paths and trails (Slight; Moderate; Severe)

Entity_and_Attribute_Detail_Citation: none

Detailed_Description:

Entity_Type:

Entity_Type_Label: soilrip.aat

Entity_Type_Definition: Arc Attribute Table

Entity_Type_Definition_Source: None

Attribute:

Attribute_Label: Soil_code

Attribute_Definition: Map unit code - final publication symbol

Attribute_Definition_Source: User Defined

Attribute_Domain_Values:

Unrepresentable_Domain: Character field

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:

U.S. Department of Agriculture, Natural Resources Conservation Service

Contact_Person: Mark Clark

Contact_Position: Soil Scientist

Contact_Address:

Address_Type: mailing and physical address

Address: 351 W. Parks Hwy, Suite 101

City: Wasilla

State_or_Province: Alaska

Postal_Code: 99654

Country: USA

Contact_Voice_Telephone: 907 373 6491

Contact_Facsimile_Telephone: 907 373 7192

Contact_Electronic_Mail_Address: mark.clark@ak.usda.gov

Hours_of_Service: 8 - 5 pm AST

Resource_Description: Soil Survey

Distribution_Liability:

Although these data have been processed successfully on a computer system at the U.S. Department of Agriculture, no warranty expressed or implied is made by the Agency regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.

The U.S. Department of Agriculture, nor any of its agencies are liable for misuse of the data, for damage, for transmission of viruses, or for computer contamination through the distribution of these data sets. The U.S. Department of Agriculture prohibits discrimination in its programs on the basis of race, color, national origin, sex, religion, age, disability, political beliefs, and marital or familial status. (Not all prohibited bases apply to all programs.)

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: ARCE

Transfer_Size: 0.2 Megabytes

Digital_Transfer_Option:

Offline_Option:

Offline_Media: CDROM

Recording_Format: UNIX

Compatibility_Information:

ISO 9660 format allows the CDROM too be read by most computer operating systems.

Fees: none

 

 

Metadata_Reference_Information:

Metadata_Date: 19990412

Metadata_Review_Date: 19990430

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: USDA/NRCS

Contact_Person: Ted E. Cox

Contact_Position: GIS Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: 351 W. Parks Hwy, Suite 101

City: Wasilla

State_or_Province: AK

Postal_Code: 99654

Country: USA

Contact_Voice_Telephone: 907-373-6493

Contact_Facsimile_Telephone: 907-373-7192

Contact_Electronic_Mail_Address: tedc@alaska.net

Hours_of_Service: 8am - 5pm AST

Metadata_Standard_Name: FGDC CSDGM

Metadata_Standard_Version: FGDC-STD-001-1998

 

 

Generated by mp version 2.3.6 on Mon May 3 12:56:48 1999

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