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Land Cover 1973 Metadata

DATASET NAME: NALC73

Identification_Information:
  Citation:
    Citation_Information:
      Originator: IMADES
      Publication_Date:
      Title:
  
  Description: Upper San Pedro Study Area land cover, 1973
    Abstract: Derived from 60-m classified NALC imagery.
    Purpose: San Pedro geodata browser web site

    Supplemental_Information:
      Data_Type: GRID
      Software: Arc/INFO 8.2
      Operating_System: Unix
      Path_Name: \SPDB\Grids\nalc73
      Reviews_Applied_to_Date: Lockheed Martin internal review
      Related_Spatial_Data_Files: All geodatasets with sp_ prefix
      References_Cited: Skirvin, Susan M., William G. Kepner, 
                        Stuart E. Marsh, Samuel E. Drake, John K. Maingi, 
                        Curtis M. Edmonds, Christopher J. Watts, and David R.
                        Williams. 2003 (in press). Assessing the Accuracy of 
                        Satellite-Derived Land-Cover Classification Using 
                        Historical Aerial Photography, Digital Orthophoto 
                        Quadrangles, and Airborne Video Data. in (R.S. 
                        Lunetta and J.G. Lyon, eds.) Remote Sensing and 
                        GIS Accuracy Assessment.  CRC Press,Boca Raton, FL.
      Notes: Additional information about the NALC project can be found at
             https://www.epa.gov/nerlesd1/land-sci/north-am.htm
      Cloud_Cover: N/A

  Time_Period_of_Content:
    Time_Period_Information:
      Single_Date/Time:
        Calendar_Date:
    Currentness_Reference:
  
  Status: Interim
    Progress:
    Maintenance_and_Update_Frequency: As needed

  Spatial_Domain:
    Bounding_Coordinates:
      West_Bounding_Coordinate:  532962.107
      East_Bounding_Coordinate:  608202.107
      North_Bounding_Coordinate: 3592633.734
      South_Bounding_Coordinate: 3426324.734

  Keywords:
    Theme:
      Theme_Keyword_Thesaurus:
      Theme_Keyword: San Pedro
      Theme_Keyword: land cover map
      Theme_Keyword: watershed
      Theme_Keyword: Landsat

  Access_Constraints:
  Use_Constraints: 

  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: IMADES
        Contact_Person: Unknown
      Contact_Address:
	Address_Type:
	Address:	
	City: Hermosillo
	State_or_Province: Sonora, Mexico
	Postal_Code:
      Contact_Voice_Telephone:
      Contact_Email_Address:

  Metadata_Reference_Information:
    Metadata_Date: 5/10/2003
    Metadata_Contact:
      Contact_Information:
        Contact_Organization_Primary: Soren Scott
          Contact_Organization: USDA-ARS-SWRC
        Contact_Address:
          Address_Type: mailing
          Address: 2000 E. Allen Rd.
          City: Tucson
          State_or_Province: Arizona
          Postal_Code: 85719-1596
        Contact_Voice_Telephone:
        Contact_Email_Address: sscott@tucson.ars.ag.gov
    Metadata_Standard_Version:


Data_Quality_Information:
  Attribute_Accuracy:		
    Attribute_Accuracy_Report: Skirvin et al., 2003
      Attribute_Accuracy_Value:
      Attribute_Accuracy_Explanation:
  Logical_Consistency_Report: Not presently available
  Completeness_Report: Not presently available
  Positional_Accuracy:
    Horizontal_Positional_Accuracy: Not presently available
    Vertical_Positional_Accuracy: Not presently available
  Lineage:
    Process_Step:
      Process_Description: 1973 NALC 60-meter imagery was classified by 
                           IMADES (Hermosillo, Sonora, Mexico). LMES clipped 
                           the imagery to the SP boundary.
      Process_Date:
      Process_Time:
 
SPATIAL REFERENCE INFORMATION
 
Grid Coordinate System: UTM
Horizontal Datum: NAD83
Zone: 12
Units: METERS
Scale: 60-meter cell base
Cell size (x,y): 60, 60
 
SPATIAL DATA ORGANIZATION INFORMATION
 
Number of Columns:  1254
Number of Rows: 2772
Grid Type: 1
Number of Classes: 10
Minimum Value: 1
Maximum Value: 10

LAND COVER CLASS DESCRIPTIONS FOR THE UPPER SAN PEDRO WATERSHED.

Forest
1
Vegetative communities comprised principally of trees potentially over 10m in height and typically characterized by closed or multi-layered canopies. Species in this category are evergreen (with the exception ofaspen), largely coniferous (e.g. ponderosa pine), and restricted to the upper elevations of mountains that arise off the desert floor.
Oak Woodland
2
Vegetative communities dominated (
  • 30% total cover) by evergreen trees (Quercus spp.) with a mean height usually between 6 and 15m. Tree canopy is usually open or interrupted and singularly layered. This cover type often grades into forests at its upper boundary and into semi-arid grassland below.
  • Mesquite Woodland
    3
    Vegetative communities dominated by leguminous trees (Prosopis spp.) whose crowns cover 15% or more of the ground often resulting in dense thickets (30-75% total cover). Historically maintained maximum development on alluvium of old dissected flood plains; now present without proximity to major watercourses. Winter deciduous and generally found at elevations below 1,200m
    Grassland
    4
    Vegetative communities dominated by perennial and annual grasses (
  • 35% total cover) with occasional herbaceous species present. Trees and shrubs do not exceed 20% of the total cover. Generally grass height is under 1m and they occur at elevations between 1,100 and 1,700m; sometimes as high as 1,900m. This is a landscape largely dominated by perennial bunch grasses separated by intervening bare ground (45-50% total cover) or low-growing sod grasses and annual grasses with a less-interrupted canopy. Semi-arid grasslands are generally positioned in elevation between evergreen woodland above and desertscrub below.
  • Desertscrub
    5
    Vegetative communities comprised of short shrubs with sparse foliage (
  • 35% total cover) and small cacti that occur between 700 and 1,500m in elevation. Within the San Pedro river basin this community is often dominated by one of at least three species, i.e. creosotebush, tarbush, and whitethorn acacia. Individual plants are often separated by significant areas of barren ground (40-45% total cover) devoid of perennial vegetation. Many desertscrub species are drought-deciduous.
  • Riparian
    6
    Vegetative communities adjacent to perennial and intermittent stream reaches. Trees can potentially exceed an overstory height of 10m and are frequently characterized by closed or multi-layered canopies depending on regeneration. Species within the San Pedro basin are largely dominated by two species, i.e. cottonwood and Goodding willow. Riparian species are largely winter deciduous.
    Agriculture
    7
    Crops actively cultivated (and irrigated). In the San Pedro River basin these are primarily found along the upper terraces of the riparian corridor and are dominated by hay and alfalfa. They are minimally represented in overall extent (less than 3% total cover) within the basin and are irrigated by ground and pivot-sprinkler systems.
    Urban
    8

    (Low and High Density)

    This is a land-use dominated by small ejidos (farming villages or communes), retirement homes, or residential neighborhoods (Sierra Vista). Heavy industry is represented by a single open-pit copper mining district near the headwaters of the San Pedro River at Cananea, Sonora (Mexico).
    Water
    9
    Sparse free-standing water is available in the watershed. This category would be mostly represented by perennial reaches of the San Pedro and Babocomari rivers with some attached pools or repressos (earthen reservoirs), tailings ponds near Cananea, ponds near recreational sites such as parks and golf courses, and sewage treatment ponds east of the city of Sierra Vista, Arizona.

    Barren
    10
    A cover class represented by large rock outcropping or active and abandoned mines (including tailings) that are largely absent of above-ground vegetation.
    Error matrix comparing aerial photo interpretation and 1973 digital land 
    cover classification. Overall accuracy = 70%. Tau = 0.66. Cohen's Kappa
    (Khat) = 0.62; standard error = 0.027. (Skirvin et al., 2003)
    REFERENCE (Aerial Photo Interpretation Class)
        1 2 3 4 5 6 7 8 9 10

    Grand Total

      1 19 1 0 0 0 0 0 0 0 0

    20

      2 1 33 0 3 0 0 0 0 0 0

    37

    1973 3 0 1 16 1 0 2 0 0 0 0

    20

    LAND 4 0 0 13 92 21 0 0 0 1 1

    128

    COVER 5 0 0 14 11 96 0 0 0 0 1 122
    CLASS 6 0 0 3 0 2 15 0 0 0 0 20
      7 0 0 3 0 7 1 10 0 0 1 22
      8 0 0 0 2 5 0 0 13 0 0 20
      9 0 0 4 3 6 0 1 0 3 3 20
      10 0 0 0 2 15 0 0 0 1 2 20
      Grand Total 20 35 53 114 152 18 11 13 5 8 429
    
    
    
     
     
     
     
     
     
     
     
     
    
    
    Land Cover Class

    1973 Map
    Total

    Photo-
    interpreter Total

    Number Correct

    Producer's
    Accuracy
    (%)

    User's
    Accuracy
    (%)

    1. Forest 20 20 19 95 95
    2. Woodland Oak 37 35 33 94 89
    3. Woodland Mesquite 20 53 16 30 80
    4. Grassland 128 114 92 81 72
    5. Desertscrub 122 152 96 63 79
    6. Riparian Forest 20 18 15 83 75
    7. Agriculture 22 11 10 91 45
    8. Urban 20 13 13 100 65
    9. Water 20 5 3 60 15
    10. Barren 20 8 2 25 10

    Total

    429

    429 299    
    
    
    ENTITY AND ATTRIBUTE INFORMATION
    ATTRIBUTE LISTING FOR: SP_NALC73.VAT
    COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED?
    1 VALUE 4 10 B -   Indexed
    5 COUNT 4 10 B -   -
    9 CLSPCT 7 7 N   -
    DOWNLOAD sp_land_cover.avl (NALC73 ArcView Legend)

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