In this lesson, you will identify and derive 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. Identifying and deriving data are the first steps in creating a suitability model.
The lesson is divided into four sections:
- Downloading and preparing the tutorial data
- Exploring the data and opening and editing the ModelBuilder model
- Using the Slope tool to derive data from base data (elevation)
- Using the Euclidean Distance tool to derive data from base data (streams)
ArcGIS Spatial Analyst extension is required for this analysis and you must ensure that it is enabled. See Enabling the Spatial Analyst extension.
These lessons were created in ArcGIS Pro using version 1.3.
Downloading and preparing the tutorial data
- Download the data package at the beginning of this case study.
- Browse to the zip file in the Downloads folder.
- Unzip the zip file named SuitabilityModeling.
- Copy the unzipped SuitabilityModeling folder (which contains Data.gdb, Output.gdb, the Toolbooxes folder, and SuitabilityModeling.aprx) onto the C drive.
Exploring the data and opening and editing the ModelBuilder model
- Open the SuitabilityModeling map document by double-clicking the file.
- To view just the Streams layer, uncheck the check boxes next to the Elevation and LandUse layers.
Streams—This layer is a feature dataset representing streams as line segments. Suitable habitat can be found in the dense riparian zones of streams.
- View the Elevation layer by unchecking the check box next to the Streams layer and checking the check box next to the Elevation layer. Click the arrow to the left of the Elevation layer check box to view a drop-down key to elevation.
Elevation—Elevation is continuous raster data that indicates the vertical height above sea level at each location.
- View the LandUse layer by unchecking the check box next to the Elevation layer and checking the check box next to the LandUse layer. Click the arrow to the left of the LandUse layer check box to view the drop-down key to the land use categories.
LandUse—Land use is categorical raster data that indicates the type of land cover present at each location.
- To help keep the workflow for building the suitability model organized, the tools used will be kept track of in a ModelBuilder model. Within the SuitabilityModeling folder is a folder named Toolboxes, with a toolbox named SuitabilityModelingToolbox, which contains the ModelBuilder model for this lesson. Access the Toolboxes folder by first clicking the Project icon under the View tab on the ArcGIS Pro taskbar.
- Create a new folder connection by right-clicking Folders and clicking Add Folder Connection to connect to the SuitabilityModeling folder.
- In the Add Folder Connection window, browse to your SuitabilityModeling folder. Click the Select button at the bottom of the window to add the folder connection.
- In the Project pane, browse to the SuitabilityModel model in the SuitabilityModelingToolbox toolbox in the Toolbooxes folder. Open the SuitabilityModel by right-clicking the model and clicking Edit.
- Drag the LandUse, Elevation, and Streams layers from the Contents pane into the model and align them vertically. These layers serve as the base data for the Habitat submodel created in this lesson.
Using the Slope tool to derive data from base data (elevation)
Ledges are often an important feature of bobcat habitat, but the elevation raster tells us little about where ledges can be found. However, a slope raster indicates where ledges are likely to exist. Derive a slope raster from the Elevation layer using the Slope tool.
- 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 Slope tool by clicking the Spatial Analyst Tools toolbox and the Surface toolset within it.
- Drag the Slope tool into the model and place it to the right of the Elevation layer.
- Double-click the Slope tool to open the tool's dialog box. You can specify file names and additional parameters on this dialog box. Choose Elevation:2 from the drop-down list of the Input raster parameter (Elevation:2 is the ModelBuilder model variable for the Elevation layer and will appear as Elevation:1 in the dialog box). Type Slope in the Output raster parameter to name the output slope raster. The model automatically saves the file into the Output.gdb geodatabase file. To summarize the input and output layers for the Slope tool, specify the parameters as follows:
- Input raster: Elevation:1
- Output raster: Slope
- Click OK to close the Slope tool's dialog box.
- Once the dialog box is closed, right-click the Slope tool and click Run to execute the tool.
- Add the Slope output layer to the map document by right-clicking the green Slope layer in the model and clicking Add To Display.
- Click the Map tab. Explore the Slope layer within the SuitabilityModeling map document. According to the legend in the Contents pane, steep slopes are displayed in white and flatter slopes are displayed in black.
Using the Euclidean Distance tool to derive data from base data (streams)
Next, a distance raster will be derived from the Streams dataset to indicate how far the nearest stream is for each location. You will derive the distance raster from the Streams layer using the Euclidean Distance tool.
- Return to the ModelBuilder model by clicking the SuitabilityModel tab. Open the Geoprocessing pane on the ModelBuilder tab by clicking the Tools icon in the taskbar at the top of the map document.
- Browse to the Euclidean Distance tool by clicking the Spatial Analyst Tools toolbox and then click the Distance toolset within it.
- Drag the Euclidean Distance tool into the SuitabilityModel model, placing it to the right of the Streams layer.
- Double-click the Euclidean Distance tool to open the tool's dialog box. Choose Streams:2 from the drop-down list of the Input raster or feature source data parameter (Streams:2 is the ModelBuilder model variable for the Streams layer and will appear as Streams:1 in the dialog box). Type Distance_Streams in the Output distance raster parameter to name the output raster. To summarize the input and output layers for the Euclidean Distance tool, specify the parameters as follows:
- Input raster or feature source data: Streams:1
- Output distance raster: Distance_Streams
- Click OK to close the Euclidean Distance tool's dialog box.
- Once the dialog box is closed, right-click the Euclidean Distance tool and click Run to execute the tool.
- Add the output Distance_Streams layer to the map document by right-clicking the green output icon and clicking Add to Display.
- 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.
- Turn on the Streams layer in the Contents pane by checking the check box to the left of the Streams layer. According to the legend, locations farther away from streams are white, whereas locations close to streams are black.
- Save the map document by clicking the Save button in the upper left corner of the ArcGIS Pro window.
At this point, you have derived data for the criteria for the bobcat habitat submodel. From the Elevation layer, a slope raster was created to predict the presence of ledges, and a distance raster was derived from the Streams layer to find the dense cover near streams. Lesson 2: Transforming data onto a common scale covers how to transform base and derived data onto a common scale so that the three criteria can be combined. Once combined, the model can identify the preference of each location relative to habitat.