At ground level, shallow seas, broad beaches, dunes, and waterlogged hollows seem to comprise a chaotic environment. In fact, there is order and form, produced by the interaction of wind, vegetation, and moving sand. Because sand dunes develop rapidly, the development of a landform can be observed. Measuring wind velocity demonstrates how saltation, sand movement, and erosion happen. The program demonstrates the morphology of dune development and how the complex interaction between it and the vegetation-soil system can be observed and measured. The program also demonstrates how precarious the balance is between the various factors, and how slight changes—including the use of the area by man—can destroy large parts of the system. (20 minutes)