N-Show: An Educational Computer Program that Displays Dynamic Graphs of Nitrogen in Soil

A careful study of the output of simulation models can help students understand concepts of crop production and soil management. Very often, graphical representation of the simulated data allows faster and easier understanding of the different processes occurring in a particular system. N-Show is an educational computer program that produces a dynamic, graphical representation of results generated by CERES—Maize, a simulation model of corn (Zea maysL.) growth and development. The program allows the user to observe and compare the results of several runs of CERES—Maize, which were selected to demonstrate the effect of soil type and N rate on nitrate leaching. N-Show displays dynamic graphs of water and inorganic N contents in the soil, N in the plant, and N leached out of the soil profile. The unique feature of N-Show is that it allows the user to move the graphical display back and forth in time, thereby allowing careful study of the events that occur at specific times. N-Show could be used in undergraduate crop and soil courses and in training sessions for extension workers and farmers.