COMPUTER SIMULATION OF DYNAMIC LANDSCAPES: EDUCATION ABOUT SPACE AND TIME

Certain topics in science and management of natural resources strain conventional approaches to communicating information among scientists, managers, regulators, and the public. One of these is the dynamic behavior of landscapes over decades to centuries. Although many academic papers are written on the subject, it is difficult to convey the richness of a four dimensional landscape in two dimensions. Many people are fascinated by images of forest fires, hurricanes, landslides, and floods, but it is not easy to explain (or learn) how these episodic and relatively rare events impact our everyday research, management, or regulation of watersheds. The availability of fast computers, computer models, and visualization software has set the stage for better communication of difficult topics. We present an educational CD titled “Landscape Dynamics and Forest Management” (Gen. Tech. Rep. RMRS-GTR-101-CD, Fort Collins, CO, USDA). The aim of the CD is to illustrate the dynamic behavior of a 200 km2 forested watershed over 500 years using state-of-the-art models of topography, forest fire, landslides, and channel processes. Forest fires kill trees leading to variation in forest ages, ranging from old growth in wide valleys to younger stands on ridge tops. Riparian trees topple into streams following fires leading to a pulse in wood recruitment and spikes in pool formation. Loss of tree rooting strength combined with large rainstorms lead to spates of soil failures within thousands of natural landslide sites. These, in turn, trigger debris flows in headwater streams that cause periods of channel aggradation and degradation within larger, fish-bearing channels. The satellite view of a 200 km2 watershed combined with a time machine that compresses hundreds of years into a few minutes conveys a sense of scale and dynamics to the viewer unattainable by other means. Instead of a relatively quiet and well behaved forest and channel system, the watershed’s forest and its channels pulse with activity. Forests are dynamic; old forests may dominate for periods but at other times not. Landslides naturally come and go. Sediment, wood, and pools in channels vary widely over time. This type of perspective has the potential to change people’s preconceived notions about the watersheds they study, manage, and regulate.