Warm nights in the Argentine Pampas: Modelling its impact on wheat and barley shows yield reductions

• Published in: Agricultural systems Vol. 162; pp. 259 - 268
• Main Authors: García, Guillermo A., Miralles, Daniel J., Serrago, Román A., Alzueta, Ignacio, Huth, Neil, Dreccer, M. Fernanda
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-05-2018
• Subjects: Climate change; Minimum temperature; Potential yield; Simulation study; Solar radiation; Temperate cereals; Climate change; Minimum temperature; Simulation study; Temperate cereals; Solar radiation; Potential yield
• ISSN: 0308-521X; 1873-2267
• DOI: 10.1016/j.agsy.2017.12.009

Efforts to anticipate how climate change and variability will affect future crop production can benefit from understanding the impacts of current and historic changes. This study aimed to quantify and compare the impact of increased night temperature on potential yield and phenology of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) crops modelled using APSIM with historical climate series (1961–2014) in sites representative of the Argentinean Pampas. For each site, the sowing date was adjusted to avoid frost and heat events at flowering, based on historical probability. The critical period was the more sensitive crop phase (shortened by 0.6d decade−1) for the observed asymmetric warming; regional minimum temperature trend of ca. 0.14 and 0.16°Cdecade−1 in wheat and barley, respectively. Wheat and barley yields declined across the region between ca. 2% and 9% per °C increase in the minimum temperature during the critical period, linked to lower cumulative radiation capture as a result of a shorter crop phase and lower incident radiation due to displacement towards winter. Regional variability in the simulated yield response to the observed night warming was mainly explained by differences the response of incident solar radiation during the critical period to the minimum temperature increase.
•A simulation study to explore wheat and barley response to night warming in the Pampas.•Potential yield declined across the Pampas due to the observed night warming.•Yield reductions linked to lower cumulative radiation capture during the critical period.•A lower radiation capture due to a shorter critical period and lower incident radiation.