Evaluate site suitability for Black Bears in the Great Smoky Mountains National Park

Problem

The Great Smoky Mountains National Park wants to relocate the Black Bear population to eliminate the problems that occur when park visitors and bears interact, especially around roads and trails throughout the park. The Park wants to find areas in the mountain that can provide water and food for the bears while shielding them from human encounter.

Analysis Procedure

Projection for all data is UTM, NAD27, zone 17, meters. The five factors to a suitable bear habitat are proximity to food, water, away from human activities, and a gentle slope. Specifically, locations that are more than 1 mile from roads and trails, less than half mile from streams, ample grape thickets and slope less than 30 degrees are most favorable. Four vector feature layers: Trails, Roads, Streams, Vegetation and one raster layer: Elevation are downloaded. To use the Weighted Overlay tool, all the vector features are to be converted to rasters and Reclassify to the same ordinal scale, so that they can be overlaid to produce meaningful results. ArcMap 10.7 is used here.

First, set the Processing Extent for all analysis to the vegetation layer. The Cell Size for all procedures was set to 30 meters. Here, the model builder was used to automate the whole process as shown in the workflow diagram below. The Slope layer was converted from Elevation using the Slope tool. The Vegetation layer was converted to raster using Feature to Raster, making sure that types of vegetation was the attribute. The Trails, Roads, Streams layers had distance added and converted to rasters using Euclidean Distance tool. I reclassified the Trails, Roads, Streams, Slope and Vegetation layers so that they all use the same scale of 1 to 3 with 3 being the most favorable. The distance buffers were in meters (same unit as layers), so I used 1 mile = 1609.344 m conversion when reclassifying. Remap files were used to simplify the reclassification. All NoData cells were kept as NODATA due to uncertainty of those cells. The reclassified layers were overlaid with each 20% weight and Evaluation scale 1 to 3 set in Weighted Overlay. The Great Smoky Mountain National Park map is now classified into three areas of suitability.

Workflow Diagram

Results

Application and Reflection

Unlike binary selection, the Weighted Overlay tool results in a range of degree of suitability. So, we have the best option, followed by the second best option and so on. This tool is often used when analyzing the environment.

Problem Description In California where the climate has been arid and windy in recent years, the USGS wants to study areas that are potential wild fire hazard. Factors to determine those areas are land cover, precipitation, temperature and land use. Most likely hazard area could be land cover with grassland, brushes, woodland, less than 3 inches of annual precipitation, consistent temperature of over 100 F and within 10 miles of developed land.

Data Needed The Multi-Resolution Land Characteristics Consortium has Land Cover and Urban Land Use data. The Monthly Temperature and Precipitation Reports - Data Tables are from NOAA. California.gov provides the land parcels polygon files.

Analysis Procedures The precipitation .csv file is converted to .xlsx and loaded into ArcMap using Add XY Data and export as a shape file which is then spatial joined to land parcels polygon shape files. This is then converted to raster using Feature to Raster. The rasters are reclassified using a scale of 1 to 3 with 3 being the Most likely hazard. The reclassified rasters are then overlaid with weights say 40% to the type of land cover since it is material to being a hazard, followed by 30% on urban land use as it pertains to the risk in the case of a fire spread and 30% evenly split between precipitation and temperature.