Within the PAstures and Climate Extremes (PACE) research program we are investigating effects of drought and warming on pasture productivity, greenhouse gas emissions and nutrient cycling.
The project is led by Sally Power at HIE and is funded by Meat and Livestock Australia’s Donor Company and Western Sydney University. The PACE facility was established in 2017 and comprises six replicate polytunnels that exclude ambient rainfall. All polytunnels have eight plots, divided in to four sub-plots; all of which are separated by root-barriers. Rainfall is manipulated using a spray irrigation system and plot warming of up to 3oC above ambient temperature is achieved via the use of infra-red heat lamps.
A variety of pasture species are being studied, including grasses such as phalaris and digit, legumes such as lucerne and sainfoin, and herbs such as chicory and plantain.
Dr Amy Churchill, Postdoctoral Research Fellow at PACE explains the experiment
Impacts of Changing Rainfall Regimes and Temperature Extremes on Pasture Systems
Forage grasses, legumes and herbs are the primary feedbase for the meat and dairy industries, with an estimated value of more than $16.5 billion in cattle, sheep, wool, dairy and meat production (Australian Bureau of Statistics). The sustainable management of grazing systems depends on the availability of high-quality forage, year-round.
A key question facing the industry is how predicted climate scenarios will affect the productivity, quality and resilience of pasture systems in the coming decades. Climate model predictions, IPCC 2013, are for Australia to experience more severe and more frequent heatwaves, greater frequency and longer periods of drought, and increases in the occurrence of flooding. These changes represent a shift towards more variable and extreme future climate conditions, including unprecedented combinations of heat and water-stress. This represents a major challenge for future pasture production, with many traditionally used species.
Developing Adaptation Strategies
The PACE facility enables us to ‘stress-test’ different combinations of plant species by exposing them to increased or reduced rainfall, increased temperatures, drought or periodic flooding, or any number of other scenarios.
The current research programme is targeting legumes, herbs and grasses with the potential to reduce ruminant methane emissions, to evaluate the impacts of future warmer, drier climates on the productivity, persistence, nutritional chemistry and anti-methanogenic properties of key forage species. We are also investigating how climate extremes affect emissions of carbon dioxide, methane and nitrous oxide – three of the most important greenhouse gasses – in these pasture systems.
Our ongoing Institute-wide research on soil biology, insect-plant interactions and climate impacts on plants and animals supports PACE research activities, offering the grazing and dairy industries new ways to proactively manage the impacts of climate change and extreme events on the feedbase that underpins their success.
Further project updates can be found in the PACE newsletters below:
“It’s like putting pasture plants in a time machine and taking them to climate conditions predicted for the future” Read more about PACE in Explainer: Dairy Australia July – Aug 2019 and
“Due to climate change, what we today perceive as ‘extreme’ conditions for pasture production may be considered ‘normal’ by the middle of this century” Read more in Western Sydney University’s Future Makers Research Magazine Ed. 2