Modelling the impacts of future climate change on mixed farming system in southeastern Australia

Abstract

Mixed farming systems play a crucial role in Australian agriculture, offering economic, social, and environmental advantages. However, these systems are vulnerable to climate change, characterized by rising temperatures and increased rainfall variability. We utilized the pre-calibrated AusFarm model, forced with daily climate data downscaled from 27 Global Climate Models, to simulate how climate change would affect mixed-farming systems at two sites, Condobolin and Wagga Wagga located in southeastern Australia. The results indicated that climate change had diverse effects on crop yields. The simulated yield for some crops, such as canola, was projected to decrease, while others, like field peas, were expected to increase. Elevated atmospheric CO₂ levels were anticipated to boost pasture production, but the overall outcome would depend on how these changes interact with rising temperatures and changed rainfall patterns. The increase in pastures was associated with higher live sheep weights and increased fleece growth, with a more significant impact observed at the drier Condobolin site. Furthermore, we found that the gross margin was projected to rise at both sites, with Condobolin experiencing more variability under the influence of climate change. These modelling findings highlight the capacity of mixed-farming systems, which integrate both crops and livestock, to uphold or even improve farm profitability in the context of impending climate change. This underscores the crucial significance of mixed-farming systems in southeastern Australia.