Seagrass_2003

Metadata also available as

Frequently-anticipated questions:


What does this data set describe?

Title: Seagrass_2003
Abstract:
2003 IRL Seagrass coverage photointerpreted from April and May 2003 1:24,000 and 1:10,000 scale natural color aerial photography from Ponce Inlet south to the Jupiter Inlet. Features were classified according to SFWMD/SJRWMD modified FLUCCS. The 2003 seagrass data was stereoscopically collected using photogrammetric techniques; ground control obtained from GPS survey and USGS DOQs, aerotriangulation of aerial photography, and stereo compilation using analytical stereoplotters. The minimum mapping unit for classification is 0.25 acres (=0.1 hectares). The horizontal accuracy of the data meets NMAS for 1:24,000 scale maps (+/- 40 feet). A thematic accuracy assessment was performed on this dataset. Pre-interpretation groundtruthing was also performed on the aerial photography, 56 field points.
Supplemental_Information: none
  1. How should this data set be cited?

    Avineon, Inc., 20040820, Seagrass_2003:, Avineon, Inc., Clearwater, FL.

    Online Links:

    • \\Windex\sjr\irl\projects\seagrass\layers\Seagrass.mdb

  2. What geographic area does the data set cover?

    West_Bounding_Coordinate: -80.975490
    East_Bounding_Coordinate: -80.051979
    North_Bounding_Coordinate: 29.102311
    South_Bounding_Coordinate: 26.939491

  3. What does it look like?

  4. Does the data set describe conditions during a particular time period?

    Calendar_Date: REQUIRED: The year (and optionally month, or month and day) for which the data set corresponds to the ground.
    Currentness_Reference: source photography date

  5. What is the general form of this data set?

    Geospatial_Data_Presentation_Form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):

      • G-polygon (6856)
      • GT-polygon composed of chains (6865)
      • GT-polygon composed of chains (6865)
      • Point (4)

    2. What coordinate system is used to represent geographic features?

      The map projection used is Transverse Mercator.

      Projection parameters:
      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -81.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.001000
      Ordinates (y-coordinates) are specified to the nearest 0.001000
      Planar coordinates are specified in meters

      The horizontal datum used is D_North_American_1983_HARN.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

      Vertical_Coordinate_System_Definition:
      Altitude_System_Definition:
      Altitude_Resolution: 1.000000
      Altitude_Encoding_Method:
      Explicit elevation coordinate included with horizontal coordinates

  7. How does the data set describe geographic features?

    Seagrass_2003

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    OBJECTID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    AREA

    PERIMETER

    SEAGRASS2003_

    SEAGRASS2003_ID

    HABITAT

    ACRES

    Shape_Length
    Length of feature in internal units. (Source: ESRI)

    Positive real numbers that are automatically generated.

    Shape_Area
    Area of feature in internal units squared. (Source: ESRI)

    Positive real numbers that are automatically generated.

    irl03_utm.pat

    FID
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    Shape
    Feature geometry. (Source: ESRI)

    Coordinates defining the features.

    AREA
    Area of feature in internal units squared. (Source: ESRI)

    Positive real numbers that are automatically generated.

    PERIMETER
    Perimeter of feature in internal units. (Source: ESRI)

    Positive real numbers that are automatically generated.

    IRL03_UTM#
    Internal feature number. (Source: ESRI)

    Sequential unique whole numbers that are automatically generated.

    IRL03_UTM-ID
    User-defined feature number. (Source: ESRI)

    HABITAT

    Entity_and_Attribute_Overview:
    
    IRL03_UTM.PAT:
    
    COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
        1  AREA                   8    18     F      5
        9  PERIMETER              8    18     F      5
       17  IRL03_UTM#            4     5     B      -
       21  IRL03_UTM-ID          4     5     B      -
       25  HABITAT               16    16     C      -
    
    AREA - predefined coverage field.
    
    PERIMETER - predefined coverage field.
    
    IRL03_UTM# - predefined coverage field.
    
    IRL03_UTM-ID - predefined coverage field.
    
    HABITAT - polygons will be annotated using a modification of the Florida Land Use
              and Cover Classification System (FLUCCS). The categories to be used are
              listed and described below.
    
      FLUCCS code 9116, Seagrass, continuous, dense --  The dominant feature of these
                        seagrass beds is that they are continuous in nature, with
                        interconnected areas of seagrass.  These beds may contain many
                        small interspersed patches of sparsely vegetated or unvegetated
                        bottom, and thus would have a lower limit of about 50 - 60%
                        cover of seagrass.  Only sand patches greater than 0.25 acres
                        should be distinguished within a continuous, dense bed.  Species
                        composition is not mapped.
    
      FLUCCS code 9113, Areas 0.25 acres or greater in size that consist of primarily
                        (greater than 50%) bare bottom in which many small patches
                        (each less than 0.25 acres) of seagrass are scattered, and
                        where the seagrass patches are not interconnected.  (For this
                        study, the lower limit of what constitutes a seagrass bed is
                        approximately 10% cover; areas with <10% cover are considered
                        "unvegetated bottom"
    
      FLUCCS code 5400, Barren substrate with little or no perceptible seagrass (<10%)
                        or only algae.
    
      FLUCCS code 9121, In a few cases, beds of algae may be distinguishable from
                        seagrass.  Where these areas are identifiable on the photography
                        AND field checked during field trips conducted for seagrass
                        mapping they should be mapped (if >10% cover), although this is
                        not a high priority and there is no intent to accurately map all
                        algae beds as part of this project.  (In some cases, drift algae
                        will accumulate in seagrass beds.  In these cases, the area should
                        be mapped as seagrass, and the density should be based on seagrass
                        density only, not algae.)
    
    
    IRL03_UTM.AAT:
    
    COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
        1  FNODE#                 4     5     B      -
        5  TNODE#                 4     5     B      -
        9  LPOLY#                 4     5     B      -
       13  RPOLY#                 4     5     B      -
       17  LENGTH                 8    18     F      5
       25  IRL03_UTM#            4     5     B      -
       29  IRL03_UTM-ID          4     5     B      -
    
    
      All Arc Attribute Table items are predefined by Arc/Info.  There is no linear
      attribution in this coverage.
    
    Entity_and_Attribute_Detail_Citation: none


Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

  2. Who also contributed to the data set?

    Avineon Inc. Photointerpretation Staff- Michael White, Daniel Bubser, Lesley Ward SJRWMD Project Manager- Robert Virnstein SFWMD Project Manager- Becky Robbins

  3. To whom should users address questions about the data?

    Keith Patterson
    Avineon, inc.
    Director- Photogrammetry, Mapping, GIS
    15500 Lightwave Drive, Suite 200
    Clearwater, FL 33760
    United States of America

    (727)539-1661 (voice)
    (727)539-6954 (FAX)
    kpatterson@avineon.com

    Hours_of_Service: 9:00AM to 5:00PM


Why was the data set created?

A primary objective of the Indian River Lagoon (IRL) Surface Water Improvement and Management (SWIM) Plan is to protect and restore seagrasses. The IRL SWIM Plan directs the South Florida and St. Johns River Water Management Districts to map seagrasses in the Indian River Lagoon at two to three year intervals. Accordingly, Indian River Lagoon seagrass maps have been prepared for the following years: 1986, 1989, 1992, 1994, 1996, 1999 and 2001.

These lagoon-wide maps, based on aerial photographs, provide an overall picture of the seagrass resources in the IRL. These maps serve as important management tools for obtaining a current inventory of this resource, identifying "healthy" areas that may deserve special protection efforts, and identifying potential "problem" areas that require further investigation. The maps can also document large-scale trends in the status of this resource.


How was the data set created?

  1. From what previous works were the data drawn?

    (none) (source 1 of 1)
    Imaging, US, Indian River Lagoon:,.

    Type_of_Source_Media: True color diapositives, stereo coverage
    Source_Scale_Denominator: 24000 and 10000
    Source_Contribution:
    photographic signature for interpretation of seagrass data.

  2. How were the data generated, processed, and modified?

    Date: 17-Jul-2003 (process 1 of 7)
    The District supplied the ground control from the 1996 mapping effort. The points were documented with hand drawn illustrations of the exact point positions as well as photocopies of the 1996 aerial photos, which highlighted the general point locations. The documentation also provided the latitude and longitude coordinates and the frame number from the 1996 aerial photos, for each point. These items were referenced to identify and transfer the points to the 2003 aerial photo layout. In 1999 Avineon had collected several new control points from USGS DOQQ's to densify the control network, filling in the gaps where necessary. The pixel coordinate values, which are embedded within the digital orthophotographic imagery, were collected for photoidentifiable features on the DOQQ image. Hand drawn illustrations were also prepared for these points. Most of the original control points were recovered from documentation and used.

    The values for the points provided from the 1996 project were expressed as geographic coordinates (latitude/longitude), NAD83, Feet. The values for the points collected from DOQ were expressed in UTM coordinates, NA83, Meters. All coordinates were transformed; using a conversion program called Corpscon, to Stateplane coordinates, NAD83, Feet.

    Date: 20-Aug-2003 (process 2 of 7)
    After GCP layout, pass and tie points were marked on the photography and then ?pugged? with a Wild PUG4 machine. Pugging is a process by which small holes (60 microns) are drilled in the emulsion on the photography. This way they are visible through the optics of the P-3 stereo plotter. Analytical measurement of all points was then done creating a file of coordinates that was exported using PAT B software for a block adjustment and densification of the ground control points. Analytical Aerotriangulation is a method of densification of photogrammetric control points using the minimum amount of Horizontal and Vertical ground control points necessary. It is performed mathematically using a least squares adjustment software. Baymont utilized PAT-B software to perform a Full Bundle Adjustment solution. The bundle method is a fully analytical method that provides a simultaneous adjustment solution of colinearity equations representing all the image rays in a Block of photography. The algorithms, in effect, use known control point positions along with camera lens calibration data to extrapolate values for unknown positions. The input for the mathematical adjustment are: photo coordinate for all control points (photogrammetric and surveyed) photo by photo, calibrated focal lens length, and ground coordinates for the orthophoto derived control points. The output includes adjusted ground coordinates of each control point to be used to orient the stereo model (or pair of photographs) and exterior parameters of the orientation of the camera (position and angles of the exposure). The resulting solution was then converted to the final coordinate file used for compilation of the mapping project on the Zeiss P-3 first order analytical stereoplotter.

    Date: 15-Aug-2004 (process 3 of 7)
    Avineon's photointerpreters used the SJRWMD/SFWMD modified FLUCCS to map the seagrass habitat within the project area. 2003 groundtruthing data, 1999 IRL Seagrass ARC/INFO coverage,and 2003 transect data collected by the District were used as collateral materials to assist in photointerpretation. Throughout the photointerpretation process, positional accuracy of seagrass habitat boundaries was maintained according to the photographic signatures apparent on the photography.

    Date: 14-Aug-2004 (process 4 of 7)
    Data compilation for the project was accomplished on Avineon's Z/I P3 analytical stereoplotters. Seagrass habitat boundaries were photogrammetrically digitized using CadMap/dgn software running on Pentium Windows 2000 workstations. Digital data georeferenced to the triangulated aerial photos is captured directly in MicroStation NT (Bentley Microsystems, Inc.) for later importation to ARC/INFO.

    Date: 15-Aug-2004 (process 5 of 7)
    At the conclusion of the photointerpretation task the Cadmap/dgn data file produced on the analytical stereoplotter was translated to ARC/INFO. Once the data was exported to ARC/INFO, processes for building topology and validating the coverage were completed. Unique identifiers (record numbers) for resulting polygons were assigned automatically by the system according to normal ARC/INFO conventions. Before generating label points for each polygon, the graphics were further validated to ensure that no dangling arcs escaped the polygon-building step. Dangling arcs were detected and corrected during an interactive ArcEdit session by technicians trained in vector polygon cleanup. A April/May 2003 seagrass polygon coverage for each of Indian River Lagoon from Ponce Inlet south to the Jupiter Inlet was delivered to the District in ARC/INFO export format on compact disc.

    Date: 15-Aug-2004 (process 6 of 7)
    Metadata created by Avineon staff using ArcCatalog.

    (process 7 of 7)
    Metadata imported.

    Data sources used in this process:

    • V:\irl\projects\seagrass\documents\irl03_utm_meta.xml

  3. What similar or related data should the user be aware of?

    ,.

    Online Links:


How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    Attribute accuracy was tested by visual comparison of the aerial photographs with the seagrass data to ensure consistency with the classification system and photo signatures. Pre-interpretation groundtruthing was also performed to aid in delineation and classification of photo signatures. Additional checks for valid attributes, as defined by the SJRWMD/SFWMD modified FLUCCS, were performed. A classification accuracy assessment was conducted 0n 200 random generated points covering the entire lagoon system the resulting accuracy for this project were 89.5%.

  2. How accurate are the geographic locations?

    Ground controlpoints were provided by the SJRWMD from the 1996 and 1999 mapping efforts. These points included both GPS survey points and control points collected from USGS 1m DOQQ's. Horizontal positional accuracy of the data meets NMAS for 1:24000 scale maps, approximately +/- 40 feet. Digital linework was reviewed over USGS DOQQ and the 1999 seagrass data. Well defined features on the images and 1999 and 2001 data were inspected for comparison to 2003 linework collected representing those features. GPS points were also collected during 2003 seagrass field work at well defined features and compared against coordinates for the same features on the 2003 data.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Minimum mapping unit for seagrass, algae beds and unvegetated bottom polygons is 0.25 acres. The study area boundary for the project was defined by the SJRWMD. Features were captured and classified according to the minimum mapping unit guideline and the SJRWMD/SFWMD modified FLUCCS.

  5. How consistent are the relationships among the observations, including topology?

    Polygon and chain-node topology present. NODEERRORS run with Dangle option. No dangles present. UNSPLIT used to remove superfluous pseudo-nodes. LABELERRORS run, with all polygons attributed. RELATE was employed to check for contiguous arcs. No arcs have the same attribute on both sides.


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:
Acknowledgement of Avineon Inc. would be appreciated in products derived from this data. The positional accuracy of this data meets USGS NMAS for 1:24000 scale maps (+/- 40 feet). A thematic accuracy for interpreted polygons representing habitat was conducted on 200 points with an overall accuracy of 89.5%.

  1. Who distributes the data set? (Distributor 1 of 1)

    St. Johns River Water Management District
    Highway 100 West, P.O. Box 1429
    Palatka, FL 32178
    USA

    386-329-4362 (voice)
    rvirnstein@sjrwmd.com

    Contact_Instructions: (contact via e-mail)
  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

  4. How can I download or order the data?


Who wrote the metadata?

Dates:
Last modified: 25-Apr-2006
Metadata author:
Avineon Inc.
c/o Keith Patterson
Director- Photogrammetry, Mapping, GIS
15500 Lightwave Drive, Suite 200
Clearwater, FL 33760
USA

727-539-1661 (voice)
727-539-6954 (FAX)
kpatterson@avineon.com

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)
Metadata extensions used:


Generated by mp version 2.8.6 on Tue Apr 25 11:08:27 2006