GeoSTAC Tutorial

  1. This example shows how the Feature and Attribute Extraction Tool can be used to find matching land areas and display the results. In this example we will find and display soil pH for corn growing soils in Wisconsin.

    Pre-Requisites

    1. Install ARCGIS 9.3/9.3.1 and SPATIAL ANALYST
    2. Download and Install GeoSTAC Tools from this website
    3. GeoSTAC Tools are available as an ArcGIS extension - make sure you have enabled this extension
    4. Make sure all your data is available in a folder \GeoSTAC_data_sets of a fast hard drive.
    5. Use the Tool Setup menu item once, to tell the GeoSTAC tools where you have installed the data.

    Notes

    • Please use the online help files for more information
    • There are two other GeoSTAC tools
    • The Join Tool links your data to geographic features with GeoSTAC
    • The Data Aggregation and Summary Tool helps you perform complex analyses and summarise data.

    START HERE

  2. Start ArcGIS - then open the GeoSTAC tools

    Open the "Feature and Attribute Extraction Tool"

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  3. Define the outline of your analysis

    The Feature and Attribute Extraction Tool has four main tabs for building and executing your query. A query is built from left to right. Complete all you need on each tab then move to the next tab to the right. Here are the salient features of the first tab.

    Geographic Extent and Output tab

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    [1] Select Geographic Extent By...

    You may select your area by choosing states (for wider area or regional analysis) or by counties (for more local analysis).

  4. Geographic Extent and Output tab

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    [1] Select Geographic Extent By...

    You may select your area by choosing states (for wider area or regional analysis) or counties (for more local analysis).

  5. Geographic Extent and Output tab

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    [2]Geographic Area of Interest

    When you select either States or Counties above you may select your Area of Interest here.

    Remember to make sure everywhere you want to analyze is selected - all the states or all the counties that you are interested in. Use CTRL-CLICK to select multiple areas.

  6. Geographic Extent and Output tab

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    [3a] Data Output Format

    First you choose the format, then the actual file name.

    There are three data output types available. You may choose an Access Table, or a Shapefile, or a Geodatabase. The Access Table output is displayed by linking the results to an existing geographic layer. It is a fast output method. The other two output formats contain an export of the boundaries of your results, so can be displayed separately from GeoSTAC data. They do however take a bit longer to process for complex queries. The personal geodatabase format is the most versatile and has the fewest restrictions.

    Remember, if you choose a geodatabase you must have already created it using ArcCatalog.

    [3b] Data Output Location

    You may select your area by choosing states (for wider area or regional analysis) or counties (for more local analysis).

  7. Geographic Extent and Output tab

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    [3b] Data Output Location and Name

    First you chose the format, now the actual file name. Locate the geodatabase (in this case note the previously created geodatabase called MyGeoStac.mdb) and name the results you will create from this query.

    In this example, since we are looking at soil pH in Wisconsin enter a relevant name such as "WI_pH_demo". Note that spaces are not permitted in the file name. This is an ArcGIS restriction.

    Key Point: Here we chose a geodatabase 'MyGeoStac.mdb' so we must have already created it using ArcCatalog.

  8. Geographic Extent and Output tab

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    Now that the Geographic Extent and Output are defined move to the "Criteria Definition" section by clicking the ""Define New Query"" button. Note that if you have already built and saved earlier queries you can load them using the "Load Existing Query" button.

  9. Criteria Definition tab

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    This section specifies the criteria that geographic features will be required to meet in order to be selected in the analysis.

  10. Criteria Definition tab

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    Choose the first criteria layers - this is the core of your query, then click "Add New Criterion". In this example, we are choosing the Census of Agriculture database ("AgCensus") in order to specify a crop production criteria

  11. Criteria Definition tab

    A new data entry form will appear that will allow you to select the crop criteria you wish to use for your query. In this example, we will be selecting Corn for Grain from the 2002 census. Several database specific forms appear - here you will work with the "Ag Census Criteria Definition"

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  12. Criteria Definition tab

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    NOTE: By checking the 'Include as a returned attribute', the query will automatically include the acres of corn as an attribute associated with the counties meeting the specified criteria.

  13. Criteria Definition tab

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  14. Attribute Definition tab

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    To specify which attribute you would like returned for the counties with greater than 50 acres of corn, click on the "Attribute Definition" tab

  15. Attribute Definition tab

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    In this example, we are interested in the soil pH for corn growing areas. The new attribute we add will be a STATSGO attribute.

  16. Attribute Definition tab

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    1. Selecting the add attribute button will open a "STATSGO Attributes" data entry form.
    2. Select the 'Soil Reaction (ph) (high)' as the attribute,
    3. select the 'Layer' as 1 (i.e. topsoil),
    4. and select the 'Component Aggregation' as Area Weighted Mean.
  17. Attribute Definition tab

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  18. Attribute Definition tab

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    In this example, we chose to display the Soil pH attribute when we ran the extraction. Other attributes requested by the query may be displayed using the standard ArcMap functionality. In this case, we are now displaying the corn acreage attribute in the map.