These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. The module is directed toward intermediate undergraduate students of the ecological sciences who are familiar with differential calculus and algebra. Frequently in the application of calculus to ecological problems, relationships between measured quantities involve rates of change of the quantities of interest, rather than the quantities themselves. Stated in mathematical terms, it is possible to determine derivatives of functions instead of the functions themselves. It is then necessary to use an inverse operation on the derivative to determine the desired function. This operation is called integration. Each function's behavior used in this module is comparable to characteristics of the ecosystem it represents. Topics are introduced and extended in the problem sets and computer exercises. (Author/CS)