The value of adapting to climate change in Australian wheat farm systems: farm to cross-regional scale

Ghahramani, Afshin and Kokic, Philip N. and Moore, Andrew D. and Zheng, Bangyou and Chapman, Scott C. and Howden, Mark S. and Crimp, Steven J. (2015) The value of adapting to climate change in Australian wheat farm systems: farm to cross-regional scale. Agriculture, Ecosystems and Environment, 211. pp. 112-125. ISSN 0167-8809

Abstract

Wheat is one of the main grains produced across the globe and wheat yields are sensitive to changes in
climate. Australia is a major exporter of wheat, and variations in its national production influence trade
supplies and global markets. We evaluated the effect of climate change in 2030 compared to a baseline
period (1980–1999) by upscaling from farm to the national level. Wheat yields and gross margins under
current and projected climates were assessed using current technology and management practices and
then compared with ‘best adapted’ yield achieved by adjustments to planting date, nitrogen fertilizer, and
available cultivars for each region. For the baseline climate (1980–1999), there was a potential yield gap
modelled as optimized adaptation gave potential up scaled yields (tonne/ha) and gross margins (AUD
$/ha) of 17% and 33% above the baseline, respectively. In 2030 and at Australian wheatbelt level, climate
change impact projected to decline wheat yield by 1%. For 2030, national wheat yields were simulated to
decrease yields by 1% when using existing technology and practices but increase them by 18% assuming
optimal adaptation. Hence, nationally at 2030 for a fully-adapted wheat system, yield increased by 1% and
gross margin by 0.3% compared to the fully adapted current climate baseline. However, there was
substantial regional variation with median yields and gross margins decreasing in 55% of sites. Full
adaptation of farm systems under current climate is not expected, and so this will remain an on-going
challenge. However, by 2030 there will be a greater opportunity to increase the overall water use and
nitrogen efficiencies of the Australian wheat belt, mostly resulting from elevated atmospheric CO2 concentrations.


Statistics for USQ ePrint 29883
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: Permanent restricted access to Published version, in accordance with the copyright policy oft he publisher.
Faculty / Department / School: Current - Institute for Agriculture and the Environment
Date Deposited: 25 Oct 2016 04:27
Last Modified: 03 Jan 2017 23:01
Uncontrolled Keywords: climate change adaptation, biophysical modeling, statistical upscaling, elevated CO2, water use efficiency
Fields of Research : 07 Agricultural and Veterinary Sciences > 0701 Agriculture, Land and Farm Management > 070103 Agricultural Production Systems Simulation
07 Agricultural and Veterinary Sciences > 0701 Agriculture, Land and Farm Management > 070105 Agricultural Systems Analysis and Modelling
07 Agricultural and Veterinary Sciences > 0703 Crop and Pasture Production > 070302 Agronomy
07 Agricultural and Veterinary Sciences > 0703 Crop and Pasture Production > 070301 Agro-ecosystem Functionand Prediction
Identification Number or DOI: 10.1016/j.agee.2015.05.011
URI: http://eprints.usq.edu.au/id/eprint/29883

Actions (login required)

View Item Archive Repository Staff Only