Goal:
The purpose of this lab will be to provide experience implementing geoprocessing tools to locate and display desired data. In addition, it will involve developing a data flow model providing a roadmap of the tools and information used to build a visual representation of the data. As a general rule, the production of maps using GIS software will include both of these elements.Background:
The study area for this exercise is located in Marquette County Michigan. The Michigan DNR would like to receive a recommendation outlining the most suitable bear habitat(s) located within the boundaries of their managed lands in this study area.Methods:
Objective 1: Add bear locations to MapThe x and y coordinates for bear locations in the study area were provided in an excel table. Through the creation of a temporary event theme, this data could be converted into a feature class displayed spatially in the study area. It was also important to set the coordinate system of the points given to the coordinate system of the geodatabase. Without this step, bear locations would not be accurately represented on the map.
Objective 2: Identify general criteria for determining conducive locations for bear habitats
In order to learn more about the habitat bears are likely to choose, the attribute table connected to bear locations needed to be connected to other data to provide context. Land-cover data was joined to the bear location data. By summarizing this data based on land-cover type, I was able to locate the three most likely categorizations for bears to reside. The three most likely land-cover types for bears to reside in were found to be Evergreen Forest Land, Forested Wetlands, and Mixed Forest Land. These selected land-cover types were extracted from the data into their own layer for future use.
Secondly, biologist's studies have shown bears are likely to be found near streams. In order to test this theory, a 500 meter buffer was placed around all of the streams in the study area. Next a "select by location" was performed to identify all of the bear locations that are within 500 meters of a stream. It turns out approximately 72% of bears in the study area are located within this prescribed boundary. Biologists would identify findings of > 30% to be significant; as a result, it does appear that proximity to a stream is an important factor in identifying ideal bear habitats.
Objective 3: Combine criteria to find the most ideal bear habitat locations
The two criteria were combined through the Intersect tool with a Dissolve applied to remove any overlapping boundaries and identify the locations that met both of our determined criteria. This intersected locations were selected and turned into their own layer for future use.
Objective 4: Combine identified area from Objective 3 with DNR management areas to provide a recommendation
The DNR provided all locations of their managed area within Marquette County. For our purposes only locations within the study area were needed. By intersecting this area with the ideal location criteria data from objective 3 and performing a dissolve, I was then able to select the management areas within our criteria and create another layer with just the area that met this new criteria.
Objective 5: Remove all areas from our ideal locations that lie within 5 km of urban land
The DNR decided, for their purposes, the ideal bear management area would be located beyond 5 km of urban urban or built up lands. After adding this data from our geodatabase, the urban land classification was selected and turned into its' own layer. Then a 5 km buffer was placed around these selected urban lands . An Erase was performed on this buffered area combined with our previously identified suitable locations to remove all selected locations within the buffer. This left us with the most ideal bear habitat locations based on the criteria established (as seen in Figure 1).
Objective 6: Building a Map
In addition to the typical map elements added to a map within ArcGIS, the legend titles needed to be adjusted for reader clarity. To provide context, Marquette County, Michigan was selected and extracted to its' own layer to provide an inset map. The same study area data was added from the geodatabase and applied to the county.
Figures:
Figure 1: This map identifies the most suitable bear habitat locations within the Marquette County, Michigan study area
Figure 2: This figure is the data flow map for the production of the map seen in Figure 1
Results:
Very few bears currently reside within the ideal locations for bear habitat identified in Figure 1. However, due to the relative scarcity of suitable locations that are also DNR managed areas, this is not that unexpected.
The DNR land to the east along Lake Michigan do not appear to be the best location for bear habitats despite its' specification as such. Bears are currently nonexistent in this area and more research should be done before such a move was made.
The DNR areas in the middle and to the west of the map appear to be the most ideal of the locations specified due to the proximity of several bear locations. From this location a line of good locations extends to the northeast.
It may be wise for the DNR to identify land to the northwest of the study area for purchase and subsequent use as a bear management area. Many bear reside in the northwest portion of the study area with a relative paucity of suitable DNR land for bear management purposes.
Sources:
All data was obtained from the Michigan Center for Geographic Information.
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