APSIM: a Novel Software System for Model Development, Model Testing and Simulation in Agricultural Systems Research

 APSIM(Agricultural Production Systems Simulator) is a software system which allows (a) models of crop and pasture production, residue decomposition, soil water and nutrient flow, and erosion to be readily reconfigured to simulate various production systems and (b) soil and crop management to be dynamically simulated using conditional rules.  A key innovation is change from a core concept of a crop responding to resource supplies to that of a soil responding to weather, management and crops. A shell of software tools has been developed within a WINDOWS environment which includes user-installed editor, linker, compiler, testbed generator,graphics, database and version control software. While the engine and modules are coded in FORTRAN, the Shell is in C++.