A new generation of climate change research
The Australian Government’s Climate Change Research Program (CCRP) was one of the most significant research efforts in Australia, according to Professor Snow Barlow from the University of Melbourne, who chaired the program’s Expert Advisory Committee.
“The CCRP marked a new emphasis on research into primary industries, which was to include climate change as one of the key elements,” he said.
“We have laid down the research foundation that will allow Australia’s farmers in the future to reduce the emissions intensity of their agricultural production — that is, the amount of greenhouse gases emitted per unit of production.”
The CCRP focused on projects to help reduce greenhouse gas emissions, improve soil carbon management, and develop adaptation practices. The Australian Government invested over $46.2 million over four years into this research which supported strong collaborative partnerships. Combined with the contribution from research agencies, rural industries research and development corporations, the total research investment was over $130 million.
“The CCRP brought research— much of which was still in the laboratory — out to the farm,” Professor Barlow said. “We applied new information and technologies directly on farms so that producers can take these innovations and use them to suit their own circumstances.
“The ultimate aim was to have farmers who are firstly knowledgeable about climate change and ready to adapt their production systems, secondly reducing greenhouse gas intensity and improving productivity in preparation for future limits on greenhouse gas emissions, and thirdly have the capacity to generate carbon credits in the future.”
Soils ain’t soils – understanding soil organic carbon
While trading in soil carbon may still be some way off, there are more immediate and practical reasons why farmers, scientists and policy makers need to better understand soil carbon.
Dr Jeff Baldock from the CSIRO led the national Soil Carbon Research Program, which developed a nationally consistent assessment of soil carbon across different agricultural regions, investigated the effect of different land management practices on soil carbon in different regions, and developed fast, cost effective ways of measuring soil carbon.
“Past agricultural practices have typically led to reductions in the amount of carbon stored in Australian soils,” Dr Baldock said.
“Some of the carbon captured by agricultural plants is removed every time a crop is harvested or an animal leaves the system. Over time, some agricultural systems have lost up to 70 per cent of carbon held in the soil.”
“That has significant impacts on day-to-day agriculture as well as contributing to greenhouse gas emissions over the long term. For example, soils with lower levels of carbon may hold less moisture, so the potential productive use of rainwater would be lower,” Dr Baldock said.
One of the problems for scientists and farmers interested in soil carbon is the lack of accurate information about how much carbon is stored in Australia’s soils and the cost of the soil tests.
However, that has changed with the work done by Dr Baldock and his team from CSIRO and State agencies. The team has used a new method for measuring the concentration of organic carbon using mid-infrared spectrometers that provide a “fingerprint” of soil carbon content and composition.
Research teams in each state have collected more than 16,000 individual soil samples from 3,500 locations across Australia’s agricultural regions. The results of the soil samples are paired with detailed history of the paddocks where they have come from to build a picture of the levels of soil carbon under different management regimes and soil types in different agricultural regions.
“The results are highly specific to climatic regions and soil types,” Dr Baldock said. “We may end up recommending certain management strategies in one region and soil type and quite different ones in different circumstances within the same region or in another region.”
Biochar - drawing on old wisdom
An ancient method of soil improvement, combined with 21st century research, is showing strong potential for increasing agricultural productivity while reducing greenhouse gas emissions.
Field and laboratory trials have been underway into the use of biochar, a stable form of charcoal created by heating natural organic materials such as wood chips, crop waste or manure in a low-oxygen process known as pyrolysis. The resulting product, which is rich in carbon, is being applied to the soil for agricultural and environmental benefit.
CSIRO has compiled a database of more than 80 biochar functions, compositions and characteristics, forming the basis for in-depth research into how different biochars affect different farm soil environments including their impacts on soil health, carbon sequestration and the mitigation of greenhouse gases. The same database was used by CSIRO to examine the potential use of biochar to increase crop productivity as part of a research project funded by the Grains Research & Development Corporation (GRDC).
According to the project’s lead scientist, CSIRO’s Dr Evelyn Krull, there is real potential for biochar to play an important role in mitigating greenhouse gas emissions while improving soil health.
“Our research was the most comprehensive on biochar to date, it looked at the production of biochars, the interaction between biochars and different soil types, the effects on productivity, the effects of climatic warming on biochar’s stability, risk factors and contamination issues, the effect of biochar on nitrous oxide emissions and the whole life-cycle of biochar and its carbon sequestration potential,” Dr Krull said.
“We found that biochar interacted strongly with soil type and as such, results from one biochar type and soil type cannot be generalised to all materials. This was particularly the case when we looked at agricultural productivity and greenhouse gas mitigation (e.g. reduction of nitrous oxide emissions from soil). However, when it comes to carbon sequestration, we now have the data that allows us to advise on which biochars are best suited for long-term (100-year time frame) carbon sequestration in soils.”
As well as the potential benefits to soil properties and enhanced crop yields under certain circumstances, producing biochar via pyrolysis can result in reduced greenhouse gases. The organic materials being pyrolysed are naturally part of the carbon cycle, so taking the carbon out of the cycle and locking it in biochar means that there is a decrease of carbon in the atmosphere.
“Trials show that biochars should last between 80 to 1,500 years in the soil, biochar could play a key role in helping to sequester carbon and offset greenhouse gas emissions,” Dr Krull said.
Life cycle assessment undertaken as part of the CCRP biochar project showed that most biochar scenarios examined led to a substantial reduction in greenhouse gas emissions. However, the assumptions applied to the reference use of the biomass means these findings are uncertain.
Computers and human brains working together – simulation software
The human brain has an inherent ability to manage risk and research scientists across Australia are working with farmers to maximise their ability to manage risk and better apply it to managing mixed farming systems in highly variable and changing climates.
The “Developing climate change resilient cropping and mixed cropping/grazing businesses in Australia” project worked with 14 farmer groups across Australia to identify activities they believe would make them resilient to climate variability and change. It used modelling to formally test how effective these adaptation options may be in terms of physical yields and farm profitability.
The researchers used a number of cropping and grazing models, including Agricultural Production Systems simulator (APSIM) software, to test changes to management options such as fallowing, fertiliser use and cropping and stocking mixes at 35 sites across the Australian wheat belt.
“The options we evaluated were put forward by farming groups in the hope that they would be resilient to both shorter term climate variability and longer term climate change,” said the project’s lead scientist, CSIRO’s Steven Crimp.
“We evaluated the options in terms of their benefits on yields, gross margins, and other economic and environmental indicators, so that producers have a clearer picture of what options may or may not work,” Dr Crimp said. “Our simulation modelling allowed us to show the outcomes of changing certain management options without the risk associated with trialing these in real life”.
“For example, APSIM simulations for Australia's wheat growing industry for the year 2070 showed that the benefits from adapting by choosing varieties for climate conditions, and optimising planting windows could be worth approximately $100 million to $500 million per annum when compared to current management practices.
“Because the work looked at the management options put forward by the farmers themselves, we were confident it gave the best chance for the science to be understood and adopted.”
As well as developing practical strategies for farmers, the project assessed how vulnerable broadacre agriculture was to climate change and what was its capacity to adapt.
“In an attempt to capture the physical, social and economic drivers of vulnerability we used survey data from the Australian Bureau of Agricultural Resource Economics and Sciences (ABARES) and the Australian Bureau of Statistics,” Dr Crimp said.
The researchers have developed a web-based vulnerability assessment tool that allows farmers to assess their own adaptive capacity, along with maps and indexes that showed areas that were vulnerable.
Looking beyond carbon – Nitrous oxide
While reducing carbon dioxide emissions in agriculture has received a lot of attention, relatively little has been paid to the role of nitrous oxide. Researchers in the Australian Nitrous Oxide Research Program (NORP) studied nitrous oxide emissions from agricultural soils in Australia and the benefits that farmers can achieve by focusing on reducing emissions of this gas.
Lead scientist, Professor Peter Grace from the Queensland University of Technology’s Institute for Sustainable Resources, said that farmers can gain immediate benefits by reducing nitrous oxide emissions.
“Nitrous oxide is principally emitted from nitrogen applied to soils,” Professor Grace said. “It is intimately linked to crop and pasture production and resource use efficiency, so reducing emissions will increase profitability.”
The research was conducted on six experimental sites across Australia, and collected real time nitrous oxide emissions data (as well as carbon dioxide, and at some sites, methane) over a broad range of irrigated, dryland, crop and pasture farming systems. Researchers used the data to compare best management practices to reduce emissions whilst maintaining agricultural productivity and profitability.
“Nitrous oxide emissions are highly variable across industries, soils, climates and management practices,” Professor Grace said. “For example, the highest emissions come from high rainfall dairy systems in southeast Australia, while irrigated cotton/cereal systems in northeast Australia and semi-arid continuously cropping systems across Australia tend to be low emitters of nitrous oxide.
“There was a great need for an increased variety of simulation modelling techniques to predict the behaviour of mitigation practices in different situations and our project helped to achieve this.
“Importantly, to maintain productivity and profitability, primary producers need to focus on reducing the intensity of emissions — that is, the greenhouse gases per unit of production — and not just overall emissions.”
Adaptation in the southern livestock industries
Researchers from the national Southern Livestock Adaptation (SLA) program used models to predict what dairy, beef and sheep grazing systems might look like under future climate scenarios.
National Coordinator Russell Pattinson said the SLA used computer models to work through future climate scenarios and their impact on current grazing systems across southern Australia.
The program has identified that most future climate scenarios predict shorter growing seasons and that some changes to farm management practices may be needed to adjust to it.
“Whether it’s changing the time of your lambing or calving, altering pasture species, introducing confinement feeding, or concentrating on genetic improvement, this program identified the management strategies that could counter the impacts of shorter growing seasons.”
Importantly, the program has shown that some adaptations that may be beneficial in the future are actually worth pursuing today.
“The best way to deal with the uncertainty of the future is to ensure you are operating as efficiently as possible now.”
Professor Barlow said that the government’s investment in the CCRP was a powerful catalyst for research into climate change adaptation and mitigation in agriculture.
“My message to farmers is that they need to be climate change aware in terms of what they’re facing now, what changes they might face in the future and how they can best work with those changes to improve agricultural production and profitability,” he said.
“They need to know what technologies and techniques they can apply to reduce emissions intensity and potentially generate carbon credits in the future. The coordinated, integrated research that was undertaken through the CCRP was a big step in the right direction.”