To run a landscape change simulation on a watershed area, the user first chooses the dependent variable whose change is to be simulated in the modeling software. Although the LUCAS GUI has a choice of three dependent variables (land cover, land use, and ownership boundaries), the current software only works with a land-cover dependent variable. Any of the other two choices for dependent variable in the LUCAS GUI will result in a warning message being posted to the user.
The user then chooses the watershed, directory of maps (mapset), and beginning map year to run the landscape change simulation on. The landscape change scenario is chosen from a list of possible scenarios which comprise pre-defined rules for generating transition probabilities reflective of certain changes in land use. Since the landscape change can be based on either a pixel or a patch based model, the user must specify whether change is determined by individual pixels or clusters of pixels having the same landscape condition label.
The number of replicates, number of timesteps, and number of maps to save are chosen from a group of slide bars on the lefthand side of the LUCAS GUI (see Figure 5). The number of replicates multiplied by the number of timesteps gives the total number of maps that will be generated. If the user does not indicate that generated maps should be saved, then no maps from the intermediate timesteps will be saved.
As noted in Section 1.1, the user can select one or more species impact modules interfaced with LUCAS. The landscape map at each timestep is evaluated for the amount of suitable habitat for the particular species that the user is interested in.
To initiate all LUCAS simulations, the user presses the Run button located at the bottom of the LUCAS GUI. At this point, the landscape change modeling program is invoked and the user interface is inactive. When the simulations are complete, a menu is realized which allows the user to display graphs of statistics generated during the landscape change simulations. A sample display of the current LUCAS graphical user interface along with output maps and graphs of summary statistics is shown in Figure 5.