Joshua Tree National Park Vegetation Mapping Project - Spatial Vegetation Data
Dates
Publication Date
2013-10-13
Time Period
1998
Summary
The U.S. Geological Survey (USGS) and the National Park Service (NPS) Vegetation Characterization Program initiated a project at Joshua Tree National Park (JOTR or Park) in 1996 to classify, describe, and map the vegetation communities of the Park. The project, including the final map, classification, and report, was completed in 2012. Initial mapping, photo-interpretation, and field work was conducted between 1996 and 2005. Final reports for these efforts were generated by 2005, including a map, ecological descriptions, classification, key, and photo-interpretation guide. Following this, a total of 1,313 accuracy assessments were conducted in 2007 and 2008, the results of which spurred additional field relev�s and a reworking of the [...]
Summary
The U.S. Geological Survey (USGS) and the National Park Service (NPS) Vegetation Characterization Program initiated a project at Joshua Tree National Park (JOTR or Park) in 1996 to classify, describe, and map the vegetation communities of the Park. The project, including the final map, classification, and report, was completed in 2012. Initial mapping, photo-interpretation, and field work was conducted between 1996 and 2005. Final reports for these efforts were generated by 2005, including a map, ecological descriptions, classification, key, and photo-interpretation guide. Following this, a total of 1,313 accuracy assessments were conducted in 2007 and 2008, the results of which spurred additional field relev�s and a reworking of the map and classification. An additional 111 relev�s were conducted in 2009 targeting problematic associations and alliances; these data were used in conducting additional analyses to produce a revised vegetation map and classification. Photo-interpretation was also redone during this time for a subset of the problematic associations and the classification was updated to match the most recent vegetation classification presented in the Manual of California Vegetation Second Edition (Sawyer et al. 2009). Between 2010 and 2011 data analysis was completed and incorporated into the final map and classification. By February 2012 the ecological descriptions were updated and completed to match (as best as possible) the most recent version of the U.S. National Vegetation Classification and the map was updated to reflect the final nomenclature.A vegetation layer created by Aerial Information Systems (AIS) for Joshua Tree National Park (JOTR) in the late 1990's. Since the initial work, an accuracy assessment (AA) was conducted during 2007 and 2008, in addition to a rapid assessment (RA) during 2009. Data collected through the AA and RA not only gauged the accuracy of the AIS's aerial photo interpretation but also the initial in-field vegetation key written by JOTR. The AA and RA data was further used in validating changes to both the vegetation layer's attribute information and polygon geometry.
The purpose of this project was to describe and map existing vegetation on 323,749 hectares (800,000 acres), within JOTR and its environs, and to provide this information in written, tabular, digital and spatial formats useful to park resource managers, the California Native Plant Society, Department of Fish and Game and others. The basic project components consist of a classification and description of the park's vegetation and a spatial database encompassing an interpretation of the vegetation from aerial imagery. This feature class represents the final vegetation layer in JOTR after AA and RA.
