摘要：Sections and subsections of the Interior Highlands of Arkansas and Oklahoma are redefined, mapped and briefly summarized. The map was produced to support the Ozark- Ouachita Highlands Assessment (OOHA), being conducted by the USDA Forest Service. It revises the USDA Forest Service map "Ecological units of the eastern United States, first approximation" by Keys et al. (1995) and the earlier maps of the natural divisions of Arkansas (Foti, 1974; Foti, 1976; Pell, 1983) to reflect new knowledge and to achieve consistency with units recognized in Missouri. Four sections (natural divisions) are defined as opposed to the three of the previous Arkansas natural divisions maps, and new subsections are recognized within most sections. Digital maps of geology, soils and topography were used to create the map in ARC/INFO. The map is accessible through the World Wide Web as a portion of a map of the entire Interior Highlands region of Arkansas, Oklahoma and Missouri on the home page of the Ouachita National Forest at http://www.fs.fed.us/oonf/ooha/welcome.htm.
