Brief Overview of Geodatabases. Procedure IT GEOGRAPHIC INFORMATION SYSTEMS LAB 9 GEODATABASE AND DIGITIZING SHAPEFILED

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1 Developing entirely new maps using on-screen digitizing to create spatial features (such as points, lines, and polygons) is a vital GIS capability. ArcGIS provides a useful, but proprietary, spatial data format for this task called a geodatabase. This Lab will focus on beginning from "scratch" to build an entirely new personal geodatabase. We'll use a DOQQ of part of Del Val College as our source reference for on-screen digitizing. There are a lot of steps involved, but follow along carefully and think conceptually and you'll be successful. Brief Overview of Geodatabases A geodatabase is a relational database containing objects that can be spatial or non-spatial. The elements of a geodatabase include object classes, which can be feature classes (i.e., contain geographic information) or tables (i.e., do not contain geographic information), annotation classes and relationship classes. Feature classes that share their extent and map projection can be grouped in feature datasets. Tables, on the other hand, cannot be contained in a feature dataset. When spatial datasets, such as shapefiles or coverage s, are exported into a geodatabase, they get converted into feature classes. A relationship class relates two objects in a geodatabase. Relationships can have one-to-one, oneto-many, many-to-one and many-to-many cardinalities. Relationships are established through keys, an origin key and a foreign key, corresponding to the origin class and the destination class, respectively. Procedure 1. Creating a Geodatabase Before creating a geodatabase, copy the Lab 9 folder from the class data folder on the H drive to your student folder. a) Using ArcCatalog, browse down to your Lab 9 working folder, right-click on it, and then click on New/Personal Geodatabase. A new geodatabase will be created in your working folder. A default name will be given to the geodatabase.

2 b) Change the name of the new personal geodatabase. The default is "New Personal Geodatabase.mdb" so make it something that will remind you of what is contained in the file. For this class be sure to begin the file name with your last name for any file that will be turned in. c) To change the name, right-click on it, then click on Rename, and rename it yourlastdelval. Now that you have created a geodatabase, the next step is to load data into it. Be sure to leave the.mdb extension. d) Right click on the newly-created file in the ArcCatalog tree. Choose New -- Feature Class. e) In the New Feature Class dialog enter a name (with NO spaces) and press the Next> button. For example, Fields would be an appropriate name for line features consisting of farm fields at DelVal College.

3 (1) Click next and set the coordinate system to Projected/State Plane/NAD 1983 (feet)/pennsylvania South FIPS 3702 and press the Next> button (2) Accept the Default for "X-Y tolerance" response and press Next>. (3) In the next dialog click on the word "Shape" in the Field Name column. The following screen will display which shows the Field Properties of the "Shape" field.

4 (4) Click the first blank cell in the Field Name column and add any attribute fields that you will want in the attribute table of your spatial features (such as Field_No for your Field file). Be sure NOT to use spaces in the Field Name (5) Click the empty Data Type cell next to the new field name and select the appropriate data type (for example, "text" for the Field_No field). Add any additional new fields (and their data types) that you will need; perhaps such things as type of crops. Press Finish. f) You've now got a new personal geodatabase ready to receive spatial data. In essence you set the specifications for the data, but currently there is still no data in the file. Notice that in the ArcCatalog display window you now have the name of your new feature class, "Fields."

5 On-screen digitizing of spatial features in a geodatabase using ArcMap Digital Orthoimagery Procedure An orthoimage is remotely sensed image data in which displacement of features in the image caused by terrain relief and sensor orientation have been mathematically removed. Orthoimagery combines the image characteristics of a photograph with the geometric qualities of a map. Delaware Valley Regional Planning Commission 2005 This project consists of the creation of 3-band, 24 bit color digital orthophoto tiles for the 5-county, Pennsylvania portion DVRPC's region utilizing a Leica ADS40 digital imaging system. The tiles were delivered in both GeoTIFF and MrSID MG3 formats. A GeoTIFF is a TIFF file which has geographic (or cartographic) data embedded as tags within the TIFF file. The geographic data can then be used to position the image in the correct location and geometry within a geographic information system (GIS) display. MrSID (Multi-resolution Seamless Image Database) is a proprietary, wavelet-based, image compression file format (*.sid) developed and patented by LizardTech, Inc. A 20:1 compresssion ratio was used for the MrSIDs. The complete data set contains 1,540 full ortho tiles in Pennsylvania State Plane South coordinate system, NAD83. The individual tiles measure 5,055' x 8,745' at a 1.0' pixel size. There is no image overlap between adjacent tiles. Orthoimagery processed by BAE Systems. The Images can be found on the PASDA website 1. Launch ArcMap and set geodatabase to the one that you just created:

6 2. Rename your data frame to Farm Field 8 and set the scales to feet.

7 3. Set the Coordinate System to Projected / NAD 1983 feet / Pennsylvania South FIPS Add the following digital orthoimage PA_X31_Y099.sid PA_X31_Y100.sid

8 5. Using "Add Data" navigate to the folder that contains your newlycreated personal geodatabase, highlight it, and press Add 6. Then highlight the feature class of your choice, such as "Fields" and press Add. 7. The Fields datafile has been added to the Layers data frame. 8. Add the Editor Toolbar (if it is not already installed) by right clicking on the blank space by the top tool bar and selecting the Editor

9 Dock the editor tool bar under the main tool bar 9. Save your map as Lab9 under the Lab_9 folder 10. Press the down arrow by Editor and choose Start Editing

10 Notice that the Task: box on the Editor bar now defaults to "Create New Feature", which is what you want to do. The Target: box lists the first (and in my case only) Feature Class (Fields) in my personal geodatabase. If you have more than one Feature Class specified, click the down area and select the Feature Class that you wish to edit. 11. Zoom to an area of College in which you wish to begin on-screen digitizing a Farm Field feature (for example the Farm 8 area). 12. Select the under the Create Features window select the polygon tool and place the first vertex of the new polygon by clicking once on any of the corners of the farm field footprint. 13. Place each subsequent vertices (moving sequentially, clockwise or counterclockwise) by clicking once on boundary of the field.

11 14. When you have placed the final vertex, right-click anywhere in the map view and select Finish Sketch. Or hit F2 15. Open the Attributes table from the Attributes Button on the Editor Toolbar.

12 a. Click on the <null> value next to the Field_No property and add 8 as the value. b. Close the window 16. Select Editor>Save Edits on the Editor Toolbar to save the new feature and its attributes to the shapefile permanently. 17. Save your Map Document Creating and Modifying Tables Using ArcView tables Tabular data are stored on the file system in one of several file formats. In ArcView tables, are a graphical representation of these tabular data sources. This means that ArcView lets us view tabular data in a GUI. So in ArcView tables have their own GUI (menus, buttons, tools), and their own set of particular operations. ArcView tables can come from a variety of sources, and multiple tables can be linked or joined based on common field values. Creating tables from existing data sources Tables can be created from many different formats of tabular data sources. Supported sources are dbase III and dbase IV, INFO (from ArcInfo), and comma- or tab-delimited ASCII files. The different formats available are chosen with a dropdown on the Add Table dialog. Here, a txt file is added to the project as a new table. Although the table is actually an attribute table that was created from a SSURGO database, the table itself can be brought into the project as a stand-alone table, apart from the coordinate half of the feature theme. When dealing with something which has many properties and many locations GIS is moving to the forefront as the tool of choice. Recognizing the role of GIS in applying the data and mapping of soils in modern agriculture, environmental management, and engineering, the United States Department of Agriculture (USDA) through its Natural Resources Conservation Service (NRCS) has made soil maps of much of the United States available to the public. These maps and data, known as SSURGO (Soil Survey Geographic Data) are available in digital formats either by ordering CDs or by download. The formats available are compatible with the most popular GIS desktops and can be quite easily used in ESRI ArcGIS. The tabular data is designed to work with one of the most popular Relational Database Managers, Micro Soft Access.

13 This project is designed to help a GIS user, student, instructor, or professional obtain, sort through and use the SSURGO data. The project is not about the soils, soil maps, or how they are created, rather it is about obtaining the data and beginning to understand how to mine the wealth of information in the data. Add a table to the map document 1. You can add the table to the map document by either dragging from ArcCatalog into ArcMap or adding the table as a document. 2. You will see the table has been added by checking the Source tab in the Table of Contents.

14 3. Right-click and Open the table. You have just downloaded a table from the web and added it in to an ArcMap document. Most of the tables we have used up to now are feature layer attribute tables. However, any supported (text, dbase, or INFO) files containing tabular data can be added in the same manner. Change the table display Tables can be altered within ArcMap, either by editing (as long as it is an editable data source), which changes the source file (on the disk), or by altering the display properties, such as hiding fields or giving field name aliases (which does not change the source data). 1. Change the table's appearance by right-clicking the table in the Table of Contents and selecting Properties from the popup menu. Note also that you can see the properties for each field (the data type, length, precision, scale, number format).

15 2. In this Lab we are going to make a slope map of Farm Field number 8. When you look at the map you see many fields with useful information but it makes it difficult to work with therefore we are only going to show the fields we want to work with. Uncheck all the fields the exception of the following and type in the Alias field what will name will be displayed; Musym Compname Slope Wtrdepth musym Mapunit Name Slope Depth to Water Table Joining and Linking Tables Joins and links are touched upon in the relational data model. In this example, we have the SSURGO table as well as the attribute table for the doylessoil ("Doylestown Soils"). The common field between these tables is musym and CFI Plot ID Number, which is the plot's identification number. Joining tables 1. Add the doylessoil shapefile to your map

16 2. Rename the Layer to Doylestown Soils 3. Right-click the Doylestown Soils layer and select Joins and Relates > Join Select the choices as below. This will join the ssurgo table to the doylessoil table, based on the musym field.

17 4. Open the Doylestown Soils attribute table. You will see the original fields. 5. Scroll to the right and you will see the joined fields have been added. For records that do not have a matched value in the joined table, the values will appear as <Null>.

18 The tables have not been physically joined (that is, joined as a single file on the disk), but are only managed this way by ArcGIS. You can verify this by adding another copy of the Doylestown Soils layer (lab9\doylessoil.shp), and open its table, which will not contain the additional fields created by the join. You have just joined two tables in ArcGIS. Use this technique to increase the informational content of your layers. You will frequently encounter layer attribute data that are minimal in content, but can be linked to other tables containing extended attributes. When a map document is saved, all of the join information is also saved, so if you open a map document, ArcGIS will reestablish any joins. Using a joined field for layer display (creating a slope map) For most of ArcGIS s purposes, the resultant table created from a join functions just like any other table. If the resultant table happens to be a layer attribute table, then ArcGIS gives you the luxury of displaying or analyzing joined data as though it were an integral part of your attribute table. Layer Display 1. Change the legend for the layer so that it is using a Unique Values display with the Value Field of slopeh, click add all values and remove the check mark in all other values. 2. Click on ok and a slope map of Doylestown Township has been created.

19 Clipping the soils layer Let s trim the Soils Layer by accessing the Clip option in the ArcToolbox 1. Click on Analysis Tools 2. Open the Extract group 3. Double click on Clip In the next dialog box, select Doylestown Soils as the input layer to clip, Farmfield as the polygon clip layer, and direct the output to your Lab_9 folder with the name farmsoilclp.shp. Choose the OK button.

20 The new layer should appear in your Farm Field 8 Data Frame. 5. Rename the new layer as Farm Field Open up the attribute table and you will notice that all of the fields from the SSURGO table exported with the shapefile when you clipped the file and made a new shapefile Remove relates and joins 1. If any joins or relates are active, you can easily remove them by making the tables active that contain relates or joins and selecting Remove Join(s) or Remove Relate(s). 2. You will need to do this when your relates or joins have gone in the wrong direction. 3. Remove the join (right-click the Dolyestown layer name and select Remove Join(s) > ssurgo.

21 Note that the classification reverts to single symbol because the field previously used for display no longer exists in the table. 4. Remove the Doylestown Soils and ssurgo layers since they are no longer needed. Creating Slope Map for Field 8 Notice that we have two slope values in the slopeh field but that some redundancy exists in the number of polygons- some of the slopes contain multiple polygon boundaries that

22 border each other. Using the new shapefile, we are going to perform a dissolve operation to reduce data redundancy. Therefore we are going to dissolve the slope field In the ArcToolbox, go to: 1. Data Management Tools 2. Generalization 3. Dissolve (double click) 4. In the next dialog box, make fieldslopeclp the input layer to dissolve, slopeh the attribute to dissolve on, and send the output to your Lab_9 folder with the name fieldslope.shp. 5. Click on ok and add the shape field to the map.

23 Review of Map Layouts New Map Document 1. Open a new map document 2. Save the document as H:\Lab_9\maps.mxd. 3. Save frequently while making map layouts. New Data Frame 1. Create a data frame and add some data 2. Create a new data frame and add the following coverages: Aerials under Lab_9 folder PA_X31_Y99.sid PA_X31_Y100.sid Shapefiles under Lab_8 folder fieldslope.shp Shapefiles under Lab_9\Map Streams.shp Camproad.shp

24 Property.shp Roads.shp Altering the polygon symbology 1. Open the property window for the fieldslope layer. 2. Change they symbologly of the layer a. Use graduated colors based on the slopeh field.

25 b. Click Symbol and select Properties for All Symbols. c. Change the Outline Color to No Color. d. Change the Display property and set the layer's transparency to 50%. This will allow the aerials to show through the slope.

26 e. Now the slopes with the 0-3 % are tan and 0-8 % are yellow. f. Add text labels for the roads layer.

27 g. Change the stream symbology to light blue with a width of 1 and the line type to stream.

28 h. Change the property layer symbology to a boundary, neighborhood line type, with a black color and a width of 1.5

29 i. Change the camproad layer symbology to a road, unpaved line type, with a red color and a width of 1.

30 j. Click on fieldslope layer and Zoom to layer.

31 k. Set the scale to 4800 Create a layout and alter properties. 1. Layouts are an integral part of ArcMap. In order to see layout view, click the Layout view icon below the lower left of the map display. 2. Change the page properties by selecting File > Page and Print Setup. 3. Set the orientation to Landscape. 4. Uncheck Use Printer Paper Settings. 5. Alter the size for a poster sized layout (Width = 11 in; Height = 8.5 in). 6. Click Scale Map Elements...

32 7. Right-click on the data frame and select Properties. 8. Set the Anchor Point at (.5,.5). 9. Change the Size to width 8 x height 7.5. Note: while it is possible to change the size and position of map elements manually with the selection handles and the pointer tool, if you set size and positions of elements using coordinate values, it is much easier to get elements to line up.

33 Title Text 1. Add a text box at the side of the map. It will be used to hold the title text. Alter its properties as below. This will give a 0.25 in gap between the text box and the map border. 2. Change the text to Field 8 Slope

34 Graphic 1. I have copied a picture of the delval logo therefore 2. Select Insert > Picture. Navigate to H:\yourlastname\Lab_9 and you will see a list of graphics files.

35 3. Alter the position to place the image in the title box. Note that Preserving Aspect Ratio will keep the image with the same proportions. The Height is selected to be offset from the title box by 0.1 in on the top and bottom. The Position sets its location also as the offset. Scale bar 1. Add a scale bar (Insert > Scale Bar). Select the Alternating Scale Bar 1 and then click Properties.

36 2. Set Division Units to feet. 3. Set When resizing to Adjust number of divisions. 4. Change Division value to Add a frame border. Increase the Gap to 2 points on each side of the scale bar.

37 Add a Legend and print the layout.