El Malpais National Monument Vegetation Classification and Map

As part of an on-going national program to inventory and map vegetation cover for all of the 280 park units in the United States, EDAC and Natural Heritage New Mexico (NHNM) developed a vegetation map for the 115,000 acre El Malpais National Monument located in western New Mexico. The rugged nature of the topography dominated by lava flows and volcanoes, some only a few thousand years old, made it especially challenging to gather field data and created much more reliance on the imagery to classify the area. Still NHNM managed to collect some 476 ground plots from 2003 to 2009 which described the vegetation cover for a sample terrain of 400 m2. These ground data sets were then used by EDAC to create a classification from multi-temporal Landsat imagery and natural color digital ortho-photography. The spectral depth and seasonality of the Landsat imagery was used to model differences in surface reflectance and phenology between vegetation types whereas the photography was used to enhance the spatial resolution of the final product. The resulting map classified the park into 12 Map Unit Level 1 classes (equivalent to the NVCS Group level) and 49 Map Unit Level 2 classes (equivalent to the NVCS Alliance level). The completed maps and accompanying reports have been provided to the US National Park Service as digital products to aid in their present and future management of their natural resources.