In lesson 1 you identified and derived the criteria for the Habitat submodel, one of the three submodels comprising the Bobcat suitability model. The two other submodels, Food and Security, will be viewed in later lessons. In this lesson you will transform the base and derived data to a common scale so that the three criteria can be combined to identify the preference for each location relative to habitat.
This lesson is divided into four sections:
- Opening and editing the ModelBuilder model
- Using the Reclassify tool to transform categorical criteria (land use)
- Using the Rescale by Function tool to transform continuous criteria (slope)
- Using the Rescale by Function tool to transform distance from streams
ArcGIS Spatial Analyst extension is required for this analysis and you must ensure that it is enabled. See Enabling the Spatial Analyst extension.
This lesson continues on the data that you downloaded in lesson 1. If you have not downloaded the data, see the first section in Lesson 1: Exploring and deriving data.
Opening and editing the ModelBuilder model
-
If the SuitabilityModeling project was closed after lesson 1, reopen it by double-clicking the SuitabilityModeling file in the SuitabilityModeling folder.
- In the Project pane, browse to the SuitabilityModel model in the SuitabilityModelingToolbox toolbox. Open the SuitabilityModel by right-clicking the model and clicking Edit.
Using the Reclassify tool to transform categorical criteria (land use)
The Reclassify tool will be used to transform the values in the LandUse layer onto a common scale. Once the land use, slope, and distance from streams criteria have been transformed onto the same scale, they can be combined into a single layer for the Habitat submodel of the suitability model. For more information on transforming data, see the Transforming data onto a common preference scale story map.
- Open the Geoprocessing pane on the ModelBuilder tab by clicking the Tools icon in the taskbar at the top of the map document.
- Click Toolboxes at the top of the Geoprocessing pane. Browse to the Reclassify tool by clicking the Spatial Analyst Tools toolbox and the Reclass toolset within it.
- Drag the Reclassify tool into the SuitabilityModel model and place it to the right of the Landuse dataset.
- Double-click the Reclassify tool icon to open the tool's dialog box. On the dialog box, you can specify file names and additional parameters. From the drop-down list in the Input raster parameter, choose Landuse:2 (Landuse:2 is the ModelBuilder model variable for the Landuse layer and will appear as Landuse:1 in the dialog box). Select VALUE for the Reclass field parameter and click Unique below the Reclassification table. Type Transformed_Landuse in the Output raster parameter to name the output raster of transformed values. The model automatically saves the file in the Output.gdb geodatabase file.
You could reclassify using the CLASS_NAMES field, but since you are only interested in the resulting reclassed values, to simplify the resulting output table and the default symbology the VALUE field will be used.
Enter the following new values into the table provided on the Reclassify tool's dialog box.
VALUE New values Descriptions (for reference only) 1
1
Developed, High Intensity
2
1
Developed, Medium Intensity
3
2
Developed, Low Intensity
4
3
Agriculture
5
4
Grassland
6
9
Forest, Deciduous
7
7
Forest, Coniferous
8
8
Forest, Mixed Deciduous-Coniferous
9
10
Scrub/Shrub
10
9
Wetland
11
2
Bare Land
12
1
Water
To summarize the input and output layers for the Reclassify tool, specify the parameters as follows:
- Input raster: LandUse:1
- Reclass field: VALUE
- Output raster: Transformed_Landuse
- Click OK to apply the changes and close the Reclassify tool's dialog box.
- Once the dialog box is closed, right-click the Reclassify tool and click Run to execute the tool.
- Add the Transformed_Landuse layer to the map document by right-clicking the green Transformed_Landuse layer in the model and clicking Add To Display.
- Click the Map tab to view the map document. Change the symbology of the Transformed_Landuse layer by first clicking the layer in the Contents pane and then clicking the Symbology icon on the Appearance tab on the taskbar.
- Choose the Unique Values symbology. Choose a red-to-green color scheme from the Color scheme drop-down list.
- Visually compare the values of the original input LandUse dataset and the reclassified Transformed_Landuse layer by checking and unchecking the Transformed_Landuse layer in the Contents pane. Make sure all other layers are turned off (unchecked) in the Contents pane. Note how the suitable areas (green), the locations with forested or shrubby cover, are more suitable than open or developed lands (red).
Using the Rescale by Function tool to transform continuous criteria (slope)
In order to combine the criteria into a single submodel, recall that each must be transformed onto a common scale. Because the slope raster is continuous data, the Rescale by Function tool will be used to transform it onto the same common scale as land use.
- Open the Geoprocessing pane on the ModelBuilder tab by clicking the Tools icon in the taskbar at the top of the map document.
- Click Toolboxes at the top of the Geoprocessing pane. Browse to the Rescale by Function tool by clicking the Spatial Analyst Tools toolbox and the Reclass toolset within it.
- Drag the Rescale by Function tool into the SuitabilityModeling model and place it to the right of the Slope layer.
- Double-click the Rescale by Function tool to open the tool's dialog box. From the drop-down list of the Input raster parameter, choose Slope(2):2. Type Transformed_Slope in the Output raster parameter to name the output transformed slope raster. Choose a Logistic growth function from the drop-down list of transformation functions. This function will transform steeper slopes as more suitable than flat areas. To summarize the input and output parameters for the Rescale by Function tool, specify the parameters as follows:
- Input raster: Slope(2)
- Output raster: Transformed_Slope
- Transformation function: Logistic growth
- From scale: 1
- To scale: 10
- Click OK to apply the changes and close the Rescale by Function tool's dialog box.
- Once the dialog box is closed, right-click the Rescale by Function tool and click Run to execute the tool.
- Add the Transformed_Slope output layer to the map document by right-clicking the green Transformed_Slope layer in the model and clicking Add To Display.
- Click the Map tab to view the map document. Change the symbology of the Transformed_Slope layer by clicking the Symbology icon on the Appearance tab on the taskbar.
- Choose a Stretch symbology, and choose a red-to-green color scheme from the Color scheme drop-down list.
- Visually compare the values of the original input Slope dataset and the rescaled Transformed_Slope layer by checking the Slope(2) layer on and checking and unchecking the Transformed_Slope layer in the Contents pane. Make sure all other layers are turned off (unchecked) in the Contents pane. Note how the suitable areas (green), the locations with steeper slopes, are more suitable than flatter lands.
Using the Rescale by Function tool to transform distance from streams
At this point in the workflow, two of the three criteria have been transformed onto the same common scale. Use the Rescale by Function tool to transform the third, distance from streams, onto the common scale.
- Browse to the Rescale by Function tool by clicking the Spatial Analyst Tools toolbox and the Reclass toolset within it.
- Drag the Rescale by Function tool into the SuitabilityModeling model and place it to the right of the Distance_Streams layer.
- Double-click the second Rescale by Function tool to open the tool's dialog box. From the drop-down list of the Input raster parameter, choose Distance_Streams:2. Type Transformed_Streams in the Output raster parameter to name the output transformed raster. Choose the MS Small function from the drop-down list of transformation functions. This function will transform areas closer to streams as more suitable than those farther away from streams. To summarize the input and output layers for the second Rescale by Function tool, specify the parameters as follows:
- Input raster: Distance_Streams:2
- Output raster: Transformed_Streams
- Transformation function: MS Small
- From scale: 1
- To scale: 10
- Click OK to apply the changes and close the Rescale by Function tool's dialog box.
- Once the dialog box is closed, right-click the second Rescale by Function tool and click Run to execute the tool.
- Add the Transformed_Streams output layer to the map document by right-clicking the green Transformed_Streams layer in the model and clicking Add To Display.
- Click the Map tab to view the map document. Change the symbology of the Transformed_Streams layer by clicking the Symbology icon on the Appearance tab on the taskbar.
- Choose a Stretch symbology, and choose a red-to-green color scheme from the Color scheme drop-down list. The green color indicates suitable locations, whereas the red indicates poor locations.
- Visually compare the values of the original input Distance_Streams dataset and the rescaled Transformed_Streams layer by checking and unchecking the Transformed_Streams layer in the Contents pane. Make sure all other layers are turned off (unchecked) in the Contents pane. Note how the suitable areas (green), the locations closer to streams, are more suitable than locations farther away.
- Save the SuitabilityModel model by clicking the Save button on the ModelBuilder tab. Click the Map tab to browse away from the SuitabilityModel model after the model has been saved.
- Save the map document by clicking the Save button in the taskbar.
At this point in the suitability modeling workflow, the land use, slope, and distance from streams criteria for the Habitat submodel have been transformed onto a common scale. In Lesson 3: Weighting and combining data, you will combine the transformed criteria into a single layer identifying the relative preference for each location based on bobcat habitat needs.