Simulating soil nitrogen transformations and its availability to plants

Nitrogen plays one of the most important roles in plant growth and production. In soil-plant-microbial system, it undergoes a series of chemical and biological transformations. These transformation processes regulate its availability to plants and also generates health and environmental concerns. It is essential to understand how biological activities and environmental factors regulate soil nitrogen transformations in order to guide farming practices for better plant production and environmental quality. This paper introduces how we use Java, Perl and XML to re-build a traditional empirical NCSOIL model into a user friendly and interactive Internet based system. The newly designed system enables users to interactively simulate how soil N transformations and its availability to plants are regulated by common farming practices and environmental factors such as tillage, soil water content and initial soil organic matter concentration. The University of Nebraska used the system to teach a Soil Resources class in the fall 2003 and conducted a survey questioning "if' and "how" this new design aided concept comprehension after the class. It is reported that it effectively helps teachers explain and students understand related concepts. This paper includes student evaluation results based on its usage in classrooms.