Description: The Habitat Evaluation Model is designed to give a composite assessment of numerous environmental variables indicating the relative sensitivity or proxy of diversity for an area of land. Because the majority of conservation in the USofA is legislated and designed around individual species recovery or protection, with relative small amounts of attention being paid to habitat values, this model in many areas bridges the gap between individual species conservation goals and the conservation goals of many sensitive species and subsequently functional parts of ecosystems. See the object model for a heuristic of the model inputs. This was originally raster based with 100ft cells that has since been dissolved and converted into a ArcINFO cover and shapefile.Geoprocessing Methodology:This entry explains the process behind joining the south county habitat evaluation model (HEM) results with the north county and east county HEM results. Because there is some overlap, it was necessary to erase some of one coverage prior to merging the two datasets. Final joined coverage name: /projects/mscp/HEM/hem_joindis The ERASE command was used to clip out the overlap between the two coverages. It was determined that the north county HEM was more robust therefore, it was used to erase the overlap from the south county HEM coverage so that the data from the north county HEM is represented in the overlap areas. Disparity between model result classes forced a generalization of the two agricultural classes in the north county HEM. In the resultant merged datasets the two agricultural classes (intensive and extensive agriculture) were aggregated into one agricultural class so that it would match that of the south county HEM. The original north county HEM data should be used for any analysis. After applying the ERASE command, the two coverages were joined using the MAPJOIN command. It was chosen because it recreates topology in the output coverage. In order to simplify the output coverage the DISSOLVE command was applied using the item "desc_mrg" as the dissolve item so that adjacent polygons with the same class would be dissolved.
Service Item Id: 5cf663ee401a4968827d3f03c308ef5b
Copyright Text: County of San Diego, Planning & Development Services, LUEG-GIS Service