Climate change and biofuel wheat: A case study of Southern Saskatchewan

Authors: WANG, HONG - Semiarid Research Center; HE, YONG - Semiarid Research Center; QIAN, BUDONG - Eastern Cereals & Oilseed Center; MCCONKEY, BRIAN - Semiarid Research Center; CUTFORTH, HERB - Semiarid Research Center; MCCAIG, TOM - Semiarid Research Center; MCLEOD, GRANT - Semiarid Research Center; ZENTNER, ROBERT - Semiarid Research Center; DEPAW, RON - Semiarid Research Center; LEMKE, REYNALD - Saskatoon Research Center; KELSEY, BRANDT - Semiarid Research Center; LIU, TINGTING - Semiarid Research Center; QIN, XIAOBO - Chinese Academy Of Agricultural Sciences; White, Jeffrey; HUNT, L - University Of Guelph; HOOGENBOOM, GERRIT - Washington State University

Submitted to: Canadian Journal of Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2011
Publication Date: 5/1/2012
Citation: Wang, H., He, Y., Qian, B., Mcconkey, B., Cutforth, H., Mccaig, T., Mcleod, G., Zentner, R., Depaw, R., Lemke, R., Kelsey, B., Liu, T., Qin, X., White, J.W., Hunt, L.A., Hoogenboom, G. 2012. Climate change and biofuel wheat: A case study of Southern Saskatchewan. Canadian Journal of Plant Science. 92(3):421-425.

Interpretive Summary: Projections for warming of North American wheat producing regions suggest that wheat yields could increase substantially, a finding that is important both for global food security and for US wheat producers who must compete in a changing global grain market. This study used a computer model of wheat growth (Decision Support System for Agrotechnology Transfer-Cropping System Model or DSSAT-CSM) to assess the potential changes in wheat production, including consideration of wheat’s potential as a biofuel crop in southern Saskatchewan, Canada. Three climate change scenarios based on IPCC scenarios for increasing greenhouse gasses were considered. Synthetic 300-yr sets of weather data were generated for the baseline period (1961-1990) and for each scenario, which corresponded to possible conditions in 2050. Compared to the baseline, precipitation increased in every month for all scenarios except in July and August and in June for A2, when it was projected to decrease. Annual mean air temperature increased by 3.2, 3.6 and 2.7 degrees C for A1B, A2 and B1, respectively. The wheat model predicted increases in biomass by 28, 12 and 16% without the direct effect of CO2 and 74, 55 and 41% with combined effects (climate and CO2) for A1B, A2 and B1, respectively. Similar increases were found for grain yield. However, the occurrence of heat shock (air temperatures over 90 degrees F) would increase during grain filling under the projected climate conditions and could reduced grain yield, an effect not simulated by the crop model. Thus, future yield under climate scenarios may be overestimated by DSSAT-CSM. Several adaptations, such as earlier planting would help avoid heat stress and take advantage of the projected increases in temperature and precipitation in the early season. These projected large impacts of climate change on wheat production could have a major effect on global wheat production and markets.

Technical Abstract: This study assessed potential impacts of climate change on wheat production as a biofuel crop in southern Saskatchewan, Canada. The Decision Support System for Agrotechnology Transfer-Cropping System Model (DSSAT-CSM) was used to simulate biomass and grain yield under three climate change scenarios (CGCM3 with the forcing scenarios of IPCC SRES A1B, A2 and B1) in the 2050s. Synthetic 300-year weather data were generated by the AAFC stochastic weather generator for the baseline period (1961-1990) and each scenario. Compared to the baseline, precipitation is projected to increase in every month under all three scenarios except in July and August and in June for A2, when it is projected to decrease. Annual mean air temperature is projected to increase by 3.2, 3.6 and 2.7 degrees C for A1B, A2 and B1, respectively. The model predicted increases in biomass by 28, 12 and 16% without the direct effect of CO2 and 74, 55 and 41% with combined effects (climate and CO2) for A1B, A2 and B1, respectively. Similar increases were found for grain yield. However, the occurrence of heat shock (>32 degrees C) will increase during grain filling under the projected climate conditions and could cause severe yield reduction, which was not simulated by DSSAT-CSM. This implies that the future yield under climate scenarios might have been overestimated by DSSAT-CSM; therefore, model modification is required. Several measures such as early seeding must be taken to avoid heat damages and take the advantage of projected increases in temperature and precipitation in the early season.