EASTERN Australia’s wheat harvest could be hammered by El Niño and its effect on cumulative soil moisture, new forecasts suggest.
University of Queensland plant scientist Andries Potgieter has modelled the effects of the strengthening El Niño on rainfall, temperature and soil moisture, and come up with a high-risk scenario for wheat growers.
Dr Potgeiter produces the OZ-W heat regional wheat yield forecasts from climate data and modelling, remote sensing and historical data.
His July models show that growers in many shires across the eastern wheatbelt face a high risk of low-yielding crops for the 2015 winter cropping season, although the effects vary from shire to shire.
Probability of exceeding the long-term simulated median shire wheat yield, using modelling based on the Southern Oscillation Index (SOI). (Potgeiter/QAAFI)
Dr Potgeiter advised growers to talk to their agronomists about crop decisions to suit their farm and region.
“Using appropriate maturity cultivars, adjusting input management in response to known soil water profiles, or even changing the crop type could help grain growers to better manage the likely impact of this El Niño event,” he said.
“Because it’s early in the winter cropping season, sowing can still occur in some areas until middle to late July in most of the cropping regions.
“However, growers should follow the ENSO status closely over the next month or two and adjust management based on the likely risks.”
El Niño has been associated with extensive drought during 17 of the past 26 events recorded in Australia since 1900.
Severe El Niño events in 2002 and 2006 had detrimental effects on crops, leading to a reduction of Australia’s total gross domestic product.
Dr Potgieter is a scientist at the Queensland Alliance for Agriculture and Food Innovation (QAAFI), a joint venture between University of Queensland and the Queensland Government.