Predicting bristlecone pine habitat in response to temperature changes
Lab: GIS course
In order to find thebest probable habitats most suitable for bristlecone pines, data layers ofgeology type, elevation and solar radiation were utilized as the initial sourcesfor analysis. The geology layer was reclassified into four broad lithographicclasses: Igneous, Metaclastics, Limestone, and Dolomite, and assigned values of“1”, “2”, “3” and “4”, respectively.
Bristlecone pines favor an elevationbetween 2990-3550 m. To reflect this preference, the DEM layer was reclassifiedto accommodate this range as “1”. Allother values were assigned a value of “0”. Solar radiation was reclassified toassign values of “2” to pixels of radiation values of 6500-7700, “1” to values5500-6500, and “0” to original values <5500 and >7700. Topographicposition was found by performing ArcMap’s Focal Statistics tool on the DEM datausing an annulus with outer radius of 300 m and inner radius of 150 m.
Topographic position data, solar radiation reclassified data and thereclassified geology type data were combined via ArcMap’s Weighted Sum tool.Topographic position was assigned a weight of 2, and the reclassified solarradiation and geology type data were assigned weights of 1. Multiplying theresultant weighted sum data layer with the reclassified DEM data produced alayer of probable bristlecone pine habitats.
