‘Biophysical and economic impact and adaptation options in a changing climate for low rainfall mixed farms, and graziers in the rangelands zone of the Murrumbidgee catchment area.’ Final Report Part 1 Baseline and projected biophysical and economic performance of 2 mixed and 4 grazing only farms in the Riverina Local Lands Services region Part 2 Evaluation of alternate management strategies on 2 mixed and 4 grazing only farms in the Riverina Local Land Services region Michael Cashen, Phillip Graham, Kim Broadfoot, Dr John Finlayson & Dr Anthony Clark April 2015 1 | P a g e Contents Acknowledgements ............................................................................................................................ 6 Executive summary ................................................................................................................................. 7 Background ............................................................................................................................................. 9 Scope of this report............................................................................................................................. 9 Biophysical models.............................................................................................................................. 9 Methods ................................................................................................................................................ 10 Site selection ..................................................................................................................................... 10 AusFarm setup .................................................................................................................................. 11 Soil characterisation ...................................................................................................................... 11 Climate (baseline) ......................................................................................................................... 11 Farming system verification .............................................................................................................. 11 Climate (projected) ....................................................................................................................... 12 CO2 fertilisation ............................................................................................................................ 14 Temporal boundaries .................................................................................................................... 14 Assessment indicators ...................................................................................................................... 15 Impact assessment ........................................................................................................................ 15 Adaptation assessment ................................................................................................................. 17 Results ................................................................................................................................................... 19 AusFarm Impact assessment - Pleasant Hills .................................................................................... 20 Pleasant Hills climate .................................................................................................................... 20 Pleasant Hills economics ............................................................................................................... 21 Pleasant Hills crop production ...................................................................................................... 22 Pleasant Hills pasture production ................................................................................................. 23 Pleasant Hills livestock production ............................................................................................... 24 Adaptation assessment – Pleasant Hills ........................................................................................... 25 Pleasant Hills sowing adaptation .................................................................................................. 25 Pleasant Hills genetics adaptation ................................................................................................ 27 Pleasant Hills cover adaptation..................................................................................................... 29 Summary – Pleasant Hills .................................................................................................................. 31 AusFarm Impact assessment - Illabo ................................................................................................ 32 Illabo climate ................................................................................................................................. 32 Illabo economics ........................................................................................................................... 33 Illabo crop production................................................................................................................... 34 Illabo pasture production ............................................................................................................. 35 Illabo livestock production ............................................................................................................ 35 Adaptation assessment – Illabo ........................................................................................................ 37 Illabo sowing adaptation ............................................................................................................... 37 Illabo genetics adaptation ............................................................................................................. 39 Illabo cover adaptation ................................................................................................................. 41 Summary – Illabo .............................................................................................................................. 43 GrassGro impact assessment – Hay East .......................................................................................... 44 Hay East climate ............................................................................................................................ 44 Hay East production summary ...................................................................................................... 45 2 | P a g e Hay East adaptation summary ...................................................................................................... 46 Summary – Hay East site ................................................................................................................... 46 GrassGro impact assessment – Hay South site ................................................................................. 47 Hay South site- climate ................................................................................................................. 47 Hay South site production summary ............................................................................................ 48 Hay South site adaptation summary ............................................................................................. 49 Summary – Hay South ....................................................................................................................... 49 GrassGro impact assessment – Hay West site .................................................................................. 50 Hay West site - climate ................................................................................................................. 50 Hay West site production summary ............................................................................................. 51 Hay West site adaptation summary .............................................................................................. 52 Summary –Hay West site .................................................................................................................. 52 GrassGro impact assessment – Narrandera ..................................................................................... 53 Narrandera climate ....................................................................................................................... 53 Narrandera production summary ................................................................................................. 54 Narrandera adaptation summary ................................................................................................. 55 Summary – Narrandera ..................................................................................................................... 55 Conclusion ............................................................................................................................................. 56 Future considerations ........................................................................................................................... 58 References ............................................................................................................................................ 59 Appendices ...........................................................................................................................................