Mississippi National River and Recreation Area, 2012 True Color Aerial Mosaic

Digital aerial imagery provides baseline data for mapping vegetation types and other land cover features. Vertical photographs (photographs taken with the aerial camera pointed straight down at the ground) collected with proper overlapping within each flight line permit an interpreter to study the photographs three-dimensionally with a stereoscope (Avery 1978) or, as with the Mississippi National River and Recreation Area (MISS) vegetation mapping project, to view stereo models of digital aerial images in three dimensions (3D) using computer workstations. Because ecologic settings are taken into account when mapping vegetation types, the ability to view the aerial images in 3D assists the recognition of those ecologic settings. During the planning stage of the MISS vegetation mapping project, existing aerial imagery of the park were researched to determine if obtaining new imagery was necessary. The findings were that existing imagery sets were not suitable to map vegetation types for the MISS vegetation mapping project because they were either 1) not current enough, 2) collected outside the fall season, and/or 3) the resolution was insufficient to properly identify vegetation to the floristic classification levels of the National Vegetation Classification Standard (NVCS). Therefore, to meet NPS VIP standards, new aerial imagery for the MISS vegetation mapping project would be acquired.