A summary of four Australian bio-economic models formixed grain farming systems

This report describes four models used to analyse Australian broadacre mixed-grain farm systems. The models that are included in this report are: IMAGINE, STEP, LUSO and APSfarm. For each model, we include a brief description of how they work, their data requirements and model outputs. IMAGINE is a bio-economic model that focuses on the impacts of tree belts on crop yields. The model accounts for the interactions between herbaceous and woody crops in terms of water and nutrient competition. Its financial analysis includes cash flow reporting. The STEP model simulates the transition from one farm system to another (mainly land-use sequence), and gives a full financial analysis of the change. LUSO simulates the impact of diseases, weeds and break crops on crop yields. LUSO reports discounted cash flows for different management strategies. The APSFarm model focuses on operational decisions. It simulates how the allocation of production and factor inputs affect farm business performance and the environment.