Vegetation - Colorado Desert [ds3198]

The purpose of this project was to create a standardized, fine-resolution vegetation dataset that meets state mapping standards and contributes to California’s statewide vegetation layer used by agencies, researchers, and the public for ecological analysis, conservation planning, and resource management. Vegetation patterns serve as a key indicator of habitat quality and ecosystem function, making accurate vegetation maps essential for understanding landscape processes and supporting decision-making. This project was sponsored by the California Department of Fish and Wildlife (CDFW) and relied primarily on 2022 NAIP 60 centimeter resolution imagery for vegetation interpretation and polygon delineation. Mapping was conducted using SCV protocols and included development and refinement of a mapping classification (typically at the alliance level), interpretation of recent aerial imagery, and delineation and attribution of vegetation polygons within the project area. Each map polygon is evaluated and attributed based on vegetation type, percent cover, disturbance impacts, hydrologic regime modifiers, and selected plant modifiers. The standard minimum mapping unit (MMU) for this project is 10 acres. Exceptions include riparian vegetation, wetlands, selected wash vegetation types, and water features, which were mapped at a 0.5-acre MMU. Land use categories (agriculture, built-up areas, and water impoundments) were mapped at a 2.5-acre MMU. Wash vegetation dominated by Atriplex polycarpa and Ambrosia salsola was mapped at a 5-acre MMU. The process also included consultation and collaboration with us by VegCAMP staff, and multiple mapping reconnaissance trips to verify vegetation interpretation in the field and update the classification as needed. A statistically supported accuracy assessment was completed using field surveys collected across the mapped area following standard VegCAMP’s Accuracy Assessment protocol. Results from the accuracy assessment were used to edit and improve the map to meet minimum accuracy standards. The overall fuzzy logic Accuracy Assessment scores for both producer's and user's accuracy were 83.6%. Final deliverables include a complete ESRI geodatabase with all vegetation attributes, documentation, and a vegetation mapping report prepared according to CDFW requirements. The vegetation mapping report is available for download here: [https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=244001] ACKNOWLEDGEMENTS We thank the local tribes for collaboration and support: Agua Caliente Band of Mission Indians, Torres Martinez Desert Cahuilla Indians, and Fort Yuma Quechan Tribe, as well as the Native American Land Conservancy, for field assistance and logistics. We are grateful to staff at Coachella Valley Conservation Commission, Coachella Valley Mountains Conservancy, Friends of the Desert Mountains, Oswit Land Trust, Sonny Bono National Wildlife Refuge, Imperial Irrigation District, Coachella Valley Water District, CDFW Imperial Wildlife Area, California State Parks (Ocotillo Wells District), and the Palm Springs and El Centro BLM Field Office for land access and permitting. We also thank UCR CCB field team members Danelle Baronia, Juniper Graham, Robin Bond, Remy Vincent, Rachel Gallardo, Brenda Fisher, and Reiley Allison.