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Topography is an important factor in determining vegetation patterns in grasslands. We collected frequency of occurrence data from transects on dune tops, south-facing slopes, north-facing slopes, and interdunal valleys in the eastern Sandhills of Nebraska to determine the effect of topographical position on plant species composition. We used canonical discriminant analysis to separate the four topographical positions based on frequency of occurrence of the 18 principal planttaxa. Topographic position played an important role in plant distribution on upland prairie with interdunal transects strongly separated from transects on other topographical positions. Bluegrasses (Poa L. spp.), switchgrass (Panicum virgatum L.), and white sage (Artemisia ludoviciana Nutt.) were highly associated with interdunal valleys. Little bluestem [Schizachyrium scoparium (Michx.)] and cool-season grasses, such as needlegrasses (Stipa L. spp.) and Junegrass [Koeleria pyramidata (Lam.) Beauv.], tended to be associated with north-facing slopes and warm-season grasses, such as prairie sandreed [Calamovilfa longifolia (Hook) Scrihn.] and sand bluestem (Andropogon hallii Hack.), tended to be associated with south-facing slopes. Sedges (Carex L. spp.), western ragweed (Ambrosia psilostachya DC.), and Scribner dichanthelium [Dichanthelium oligosanthes (Schult.) Gould var. scribnerianum (Nash)] were the most common taxa occurring over all topographic positions. Aspect proved to be an important factor in influencing vegetation distribution in the eastern Sandhills of Nebraska.