Vegetation Map of Mojave Desert National Preserve and Castle Mountains

A 1.6-million-acre vegetation map documents 136 plant associations and 67 plant alliances across the Mojave National Preserve and Castle Mountains National Monument. The project, initiated by the National Park Service in 2010, used data from 630 field plots and achieved a map accuracy of 91%.

Use Cases

• Train a geospatial model to classify the 136 plant associations using spectral data from the 2018 NAIP basemap.
• Analyze the distribution of Joshua tree forests and other desert ecosystems across the 1.6-million-acre study area.
• Validate land cover change models using the 91% accurate vegetation map with a 1.2-acre minimum mapping unit.
• Study plant community composition by linking the 67 documented alliances to environmental variables like landform type.

Strengths

• High map accuracy of 91% with a Kappa value of 92%, indicating reliable classification.
• Covers a large 1.6-million-acre area with a detailed minimum mapping unit of 1.2 acres.
• Based on field data from 630 plots and observation points, supplemented by 588 samples from prior studies.
• Project conducted over a 10-year period (2011-2021) with a defined six-phase methodology.

Limitations

• Data is a static snapshot based on 2018 NAIP imagery and field work ending in 2021, not a time series.
• The 1.2-acre minimum mapping unit may not capture fine-grained vegetation patterns or rare species occurrences.
• Focus is limited to two specific protected areas (MOJA and CAMO) within the Mojave Desert.

Provenance

Source

National Park Service’s Vegetation Mapping Inventory (VMI), in collaboration with California Native Plant Society and University of Nevada, Las Vegas.

Collection Method

Hybrid mapping combining manual and automated techniques on NAIP imagery, validated by ground verification from 630 field plots.

Time Range

Project phases conducted between 2011 and 2021; basemap imagery from 2018.

Freshness

Data collection concluded in 2021; map is based on 2018 imagery.

Geography

Mojave National Preserve and Castle Mountains National Monument along the California-Nevada border.