Vegetation mapping inventory project: Death Valley National Park

This study presents a comprehensive vegetation mapping inventory project undertaken in Death Valley National Park (DEVA) within the National Park Service’s Mojave Desert Network (MOJN). Spanning 3.4 million acres across California and Nevada, DEVA is the largest national park in the contiguous United States. Renowned for its harsh environment—characterized by intense heat, aridity, and low elevation—DEVA encompasses a variety of landscapes, including playas, alluvial fans, sand dunes, and mountain ranges. Despite its desolate appearance, the park harbors a diverse array of vegetation, with plant communities adapted to the park’s varying elevation, moisture, salinity, and substrate conditions. The project, which began in 2011, was initiated by the National Park Service’s (NPS) Vegetation Mapping Inventory (VMI), aimed to document and classify the plant communities within DEVA. The ten-year project, divided into six phases, began with a thorough review of legacy data and a summary of plant communities. In collaboration with the California Native Plant Society (CNPS) and the University of Nevada, Las Vegas (UNLV), field data were collected across the park, including 111 classification plots and 518 observation points. This data, along with 1,242 samples from previous studies, were entered into the NPS VMI-specific PLOTS database. The CNPS analyzed the collected data to classify 85 plant alliances according to the revised US National Vegetation Classification (rUSNVC) standard, leading to the identification of 186 plant associations within DEVA. Cogan Technology, Inc., then developed a digital vegetation map layer covering the entire park, using a combination of manual and automated mapping techniques. This map was based on imagery from the National Agriculture Imagery Program (NAIP) and field data, resulting in the delineation of 90 map units (74 vegetated and 16 land-use/land-cover units). The map’s overall thematic accuracy was assessed at 82%, with a Kappa value of 89%. The final products, including the spatial geodatabase, digital vegetation map layer, field photos, metadata, classification report, and a field key to the vegetation alliances, were delivered to the NPS VMI. These resources provide a comprehensive overview of DEVA’s vegetation and support ongoing conservation and management efforts within this unique and challenging landscape.