Mr Paul Sanford1, Dr Meredith Gutherie2, Dr Imma Farre2, Mr Sud Kharel2, Clinton Revell2, Ms Janet Conte2, Dr Kevin Foster2
1Department of Primary Industries and Regional Development, Albany, Australia, 2Department of Primary Industries and Regional Development, Perth, Australia
Biography:
Paul has been involved in plant research for over 40 years, firstly investigating the nitrogen nutrition of legumes before moving to livestock systems based on perennial grasses. Paul is best known for his work with the sub-tropical grass kikuyu and is currently contributing to the development of year round forage systems and pastures that are adapted to future climate.
Abstract:
The South West of WA has been becoming drier and hotter since the 1970’s and future projections indicate this trend will continue – presenting challenges for pasture and livestock production. The FutureSheep project is investigating how producers can adapt to this change in climate. Using 8 farm case studies this investigation used the model GrassGro™ to predict the pasture productivity of each farm in 2050. To generate the climate data for 2050 for two greenhouse gas pathways (representative concentration pathways (RCP) 4.5 and 8.5), change factors were obtained from the Climate Change in Australia website. Using these factors, daily rainfall and temperature for 2050 was calculated using historical 2002-2021 data. Atmospheric CO2 levels were set at 395 ppm for the current climate, 500 ppm for 2050 RCP 4.5 and 610 ppm for 2050 RCP 8.5. All simulations were ungrazed annual pasture run for 20 years. GrassGro™ was validated for each of the case study sites using the Pastures from Space ™ data for the period 2004 to 2021. The resulting simulations suggest that all sites will experience a loss in pasture yield by 2050, with the lower emission pathway (RCP 4.5) resulting in the least reduction in most cases. Yield at low to medium rainfall sites is expected to decline by an average of 20% compared to only 6% at higher rainfall sites. The results also suggest that the growing season in 2050 will be shorter at all sites.