This paper is part of a larger study entitled "A Comparative Geography of Three Ecologically Similar Regions," which compares the Chesapeake Bay region of Maryland with the Murray River region of South Australia and the Rio de la Plata region of Uruguay. Readings with accompanying questions are intended for classroom use. Teachers are encouraged to draw upon other resources to add more depth to this unit. Suggestions for using comparative geography of the regions are included. Test questions are attached. (EH)