Development, Testing And Implementation Of A Generic Pasture Growth Model (CLASS PGM) 1

This paper describes the development and testing of a generic pasture growth model CLASS PGM (Vaze et al., 2004b) which can be used to simulate growth of composite pasture types of multiple species that may be summer or winter active, perennial or annual. The model includes carbon assimilation through photosynthesis and respiration followed by tissue growth, turnover and senescence. Environmental conditions as well as soil water, nutrient and salinity status influences pasture growth and tissue dynamics. The model allows the user to simulate a range of grazing management strategies. Concepts and theoretical basis of the pasture growth model is based upon the detailed technical report on pasture and crop growth modules (Johnson, 2003). The model is supported by the Richards’ equation- based hydrology tool, Unsaturate