Goals and Background
The goal of this lab was to use various geoprocessing tools for vector analysis to determine suitable habitat for bears in the study area of Marquette County, Michigan.
Work Flow
Starting off the lab, I had to make sure to create a lab 3 folder in my Q drive for the class in order to save all of the data I was going to create in this lab. I then moved on to objective one. I explored the data that was given in the lab 3 folder and made sure everything looked correct and was ready to be imported into ArcMap. I first needed to import the excel file with all of the bear locations into ArcMap as an event theme. There were screenshots that helped me figure out this part. Once the coordinates from the excel file were mapped then I had to export them to my geodatabase as a feature class.
In objective two I began by adding all of the feature classes within the bear_management_area feature dataset. I changed the symbology for the landcover layer to a unique value map in order to see the different types of land cover in the "minor type" field. I then opened the bear locations attribute table in order to see that there is just an ID number for each bear. I wanted to find what land covers these bear ID's were in when GPS data was recorded. I did a spatial join with bear locations being the source and land cover as the destination. I was a 1:1 simple inside join that resulted in a new feature class called bear cover which showed which bears were in each land cover type. I then summarized the Object ID with the minor type field in order to get the top three land covers in which most bears were located. These were Mixed Forest Land, Forested Wetlands, and Evergreen Forest Land.
Objective three then began to focus on the streams in the study area. I created a buffer within 500 meters of the streams and then dissolved the internal boundaries so it looked more pleasing. I then created a feature class out of this buffer because it is necessary in order to complete the rest of the lab. I found that 72% of the bear locations were within 500 meters of a stream which makes this an important habitat characteristic.
In objective four I needed to find suitable areas of bear habitat for the study area based on my research so far. My two criteria I needed to take into consideration were suitable land cover types (top three covers in which bears were found in) and areas within 500 meters of the streams in the study area. I started my intersecting my new streams layer and the suitable land cover layer. After I intersected these two layers I dissolved them in order to get rid of the internal boundaries.
For objective five I needed to find suitable bear habitat areas located within DNR management lands. I intersected my layer from objective four and the DNR management layer. I then dissolved to get rid of internal boundaries.
Objective six required me to create a new layer from the land cover layer. I selected the Urban areas within land cover and made it it's own layer. From there, I created a buffer 5 kilometers around these areas because bear habitats shouldn't be found within this distance of Urban areas. After this buffer I ran the clip tool and then the erase tool in order to get suitable land within an Urban area. This land would be suitable for bear habitats if only there wasn't an Urban area nearby.
Objective seven required me to create a map of the data I had created which is pictured below.
Results
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| Figure 1: Suitable bear habitat final product. |
The tan color in the study area are the suitable areas for bear habitats in Marquette County, Michigan. The green portion in the map would be suitable areas, but they are within 5 kilometers of an urban area so they are not actually suitable areas. The red points are bear locations recorded with GPS. In the upper data frame with the state of Michigan we can see where Marquette County is.
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| Figure 2: Data flow model for lab 3. |
>>> import arcpy
>>> arcpy.Buffer_analysis("Streams", "Streams_buf", "1 kilometer", "FULL", "ROUND", "ALL")
<Result 'H:\\Documents\\ArcGIS\\Default.gdb\\Streams_buf'>
>>> arcpy.Intersect_analysis(["Streams_buf", "suit_land"], "land_stream")
<Result 'H:\\Documents\\ArcGIS\\Default.gdb\\land_stream'>
>>> arcpy.Buffer_analysis("Streams", "Streams_buf", "1 kilometer", "FULL", "ROUND", "ALL")
<Result 'H:\\Documents\\ArcGIS\\Default.gdb\\Streams_buf'>
>>> arcpy.Intersect_analysis(["Streams_buf", "suit_land"], "land_stream")
<Result 'H:\\Documents\\ArcGIS\\Default.gdb\\land_stream'>
We also needed to try out Python when we were done with our map. I had a bit of trouble with it at first, but I figured it out eventually. I would really like to gain more knowledge on how to use Python better because I find it really interesting.
Sources
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