Geography 335- Introduction to GIS: GIS I Lab 4: Vector Analysis with ArcGIS

Goal: To use various geoprocessing tools for vector analysis in ArcGIS to determine suitable habitat for bears in the study area of Marquette County, Michigan.

Background: The Michigan DNR would like to be able to see which areas within their management should be studied for suitable bear habitats.

Methods:

Objective 1: Add bear points and give them a spatial position

To first begin the process, I needed to attain all of the data from our class folder, which contained the USGS and DNR information on the bears locations and landcover. In order to use the X, Y coordinates that the individual bears were identified with, a created a temporary ‘event theme’. To use the coordinates in the map, I needed to ‘add data’, ‘add x y coordinates’, set the coordinates to match the geodatabases’ coordinate system, and then export the data to create a feature class of the bear location points.

Objective 2: Determine the bear habitat

In order to figure out what kind of habitats bears live in, I needed to perform a spatial join for the bear_locations and landcover feature classes. This then enabled me to access the attribute table and determine what the top three forest types are most popular for bears.

Objective 2b: Are streams important to bear habitats?

Because bears are often seen near streams, I wanted to determine how vital that body of water is for bear habitats. To do this, I used a select by location; I used the bear_cover as the target layer and the streams as the source layer. This enabled me to calculate all bear location points within 500 meters of a stream. I found out that 72% of bears reside near streams, therefore it is a very important habitat characteristic.

Objective 3: What are the suitable areas of bear habitats based on research in Marquette County Michigan?

To figure out which areas are suitable for bears, I used ArcToolbox to create a buffer for the ‘streams’ feature class to 500 meters, which created a layer. Following that, I used the intersect tool to highlight the land polygons that intersected with the streams. The input used for this tool was the buffer_streams and sut_land. In order to remove the internal boundaries of the overlaying polygons, I used the dissolve tool and used the streams_buffer_intersect as the input. This cleaned up the image to make it appear cleaner.

Objective 4: Make a recommendation for the Michigan DNR based on the area of land they manage

To only include the areas of the DNR management within Marquette County, I used the ArcToolbox to clip the segments out. This was done by using the study_area as the input and the dnr_mgmt as the clipped portion. The next step was to intersect the dnr_study and streams_buffer_intersect_dissolve to create the DNR suitable area.

Objective 5: Take away bear habitat study possibilities up to 5 km away from urban land.

In this step it was critical to make a layer called urban_land with the ‘Urban or Built Up Land’ within the major type field within the landcover data. This allowed me to create a 5-kilometer buffer around the urban areas. From this I conducted an erase on the landcover_buffer so all of the previously suitable land within the 5 kilometers of urban land was erased. This left me with the bear habitat 5 kilometers away from the urban landcover.

Objective 6: Report results in a map and a blog post.

I first cleaned up the legend of the map by renaming the feature classes in order to clarify the symbols for the viewers. The map includes the location of the bears, streams, and the results from objective 3 and objective 5. I added a north arrow and a scale bar for orientation and size purposes. In addition, to understand the location of Marquette County in Michigan, I created a locator map highlighting the county within a map of Michigan. In addition, I added the sources from which the data was collected.

Figures: