Vegetation inventory, mapping, and characterization report, Coronado National Memorial

Studd, Sarah; Galvin, Jeff; Hubbard, J.

The Sonoran Desert Network conducted a vegetation mapping and characterization effort at Coronado National Memorial (NMEM) from 2010 to 2016. This project was completed under the National Park Service (NPS) Vegetation Inventory Program, which aims to com-plete baseline mapping and classification inventories at more than 270 national park units. The goal of the project was to provide park managers with a digital map product that meets national standards of spatial and thematic accuracy, while also placing park vegetation into a regional and national context. The data standard was designed to facilitate the production of uniform statistics about vegetation across the nation; enable the translation of data collected at various scales; and allow data sharing, aggregation, and comparison across regions. Vegetation mapping and characterization comprised three major field phases: (1) concur-rent, field-based data collection and mapping from aerial imagery (map unit delineation), (2) development of vegetation community types at the National Vegetation Classification association level, and (3) map accuracy assessment. The majority of Phase 1 (sampling of all classification plots and 60% of the classification polygons) was completed during fall 2010. In summer 2011, the project was placed on hold due to the Monument Fire. Sampling of classification polygons was eventually completed in 2013 and 2014, and incorporated the ef-fects of the Monument Fire. All map units (polygons) were delineated by hand, using printed satellite imagery and other spatial data in the field to guide the process. Twenty-five new community type descriptions were drafted within the National Vegetation Classification System (NVCS) standard and applied to each of the mapped areas. The park-based vegetation community classification was developed from both plot data and field-census polygon data (map units). An accuracy assessment was completed in 2016. Following accuracy assessment, final products were developed, including this report, a digital map, and full vegetation community (“association”) descriptions. Coronado National Memorial covers 1,922 hectares (4,750 ac) along the border between the U.S. and Mexico. Elevations range from 1,447 meters (4,750 ft) along the southeast bound-ary to 2,377 meters (7,800 ft) in the northeast corner. A total of 25 distinct communities were described and mapped at the park, ranging from dense, non-native grasslands dominated by Lehmann lovegrass (Eragrostis lehmanniana) to steep expanses of exposed bedrock domi-nated by mountain mahogany (Cercocarpus montanus) and evergreen sumac (Rhus virens). Four of the 25 vegetation types were existing, “accepted” types within the National Vegeta-tion Classification (NVC). The others are new and specific to Coronado National Memorial, and are currently proposed for formal status within the NVC. Ten species were observed that have a global rarity rank of G3 (see Table 4-1), defined as “Vulnerable–at moderate risk of ex-tinction due to a restricted range, relatively few populations, recent or widespread declines, or other factors” (natureserve.org). Of these, two species also had comparable state rankings: one S3 (“uncommon or restricted”) ranking for dentate falsepennyroyal (Hedeoma dentate) and one S1 (“very rare”) ranking for Arizona yellowhood (Nissolia wislizeni). The project products are designed to facilitate ecologically based natural resource man-agement and research. The vector (polygon) map is in digital format within a geodatabase structure that allows for complex relationships to be established between spatial and tabular data, and allows much of the data to be accessed concurrently. The Geographic Information System (GIS) format allows user flexibility and will also enable updates to be made as new information becomes available (such as revised NVC codes or vegetation type names) or in the event of major disturbance events that could impact the vegetation.

Vegetation inventory, mapping, and characterization report, Coronado National Memorial

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