In this lesson students investigate the science behind managing methane production in ruminant livestock production.
Students will have the opportunity to:
- recognise the role of knowledge of the environment and ecosystems in a number of occupations
- describe how technologies have been applied to modern farming techniques to improve yields and sustainability
- use information and knowledge from their own investigations and secondary sources to predict the expected results from an investigation
- use digital technologies to construct a range of text types to present science ideas
- select and use appropriate language and representations to communicate science ideas within a specified text type and for a specified audience.
Setting the context
The digestion of ruminant animals produces a waste by-product — methane.
As well as being the most potent greenhouse gas, it is a waste of energy. If the energy used to produce methane can be redirected, animal growth can be improved.
The Australian Government has instituted the Carbon Farming Initiative (CFI) to support farmers who reduce emissions. This initiative aims to deliver financial incentives to farmers who use CFI approved technologies that reduce emissions.
One area of current research is investigating the impacts of different diets on methane emissions from livestock. Initial research results suggest some pastures and forage shrubs result in lower methane emissions than others (e.g. legumes, such as clover and lucerne, produce less methane during ruminant digestions than grasses, such as perennial ryegrass and phalaris)
The focus of this lesson is to encourage students to adapt their knowledge of what they have learned so far about ruminant digestion to address the issue of methane production in livestock industries.
Explain to students that in this lesson they will be investigating the science and technology Australian livestock producers are using to reduce methane emmissions in sheep and cattle systems in Australia. To begin the lesson ask students a range of questions, reviewing the previous lesson, to establish their current understanding of the link between ruminant digestion and methane production.
Body of lesson
- Ask students to read the ABC Science article Methane myth gives cattle a bum steer or listen to the audio file online.
- Ask students to share their ideas about how livestock producers might manage the level of methane emissions from their livestock. Record students’ ideas on the board or in a class science journal. Explain to students that scientists are working with livestock producers to investigate ways to manage methane emissions from livestock. Allow students to read the article: FARM300 Increasing productivity to lower emissions intensity from page 48 Beyond the Bale magazine March 2015.
Review students’ ideas in light of the management options outlined in the table at the end of this article.
- Explain to students they are going to investigate some case studies of Australian farmers who are adapting their management practices to maintain or improve productivity while reducing the overall methane emissions from their livestock enterprises. Separate students into small project groups. Visit the MLA Farm300 website and ask each group to select a farmer case study to investigate. Some of the case studies are listed below
- SA cattle producer Sandy Nott — Investigating grape marc as a supplementary feed source
- NSW sheep producer Tom McGuiness focused on matching stocking rate with feed availability and the changing climate.
- Victorian mixed farmer Simon Ross measured the efficiency, emissions and profitability of the farm’s sheep feedlot.
- SA cattle and sheep producer Janet Furler — alternative pasture species and feed to fill feed gaps, increase efficiencies and reduce methane emissions.
- Ask students to review these case studies and using a digital format (such as powerpoint or slideshare) develop a presentation that outlines:
- the relevant production system (e.g. location and livestock type — sheep or cattle)
- feedbase — pasture, novel feed, grain
- the innovation or management change employed (e.g. change in grazing management, change in feedbase)
- the results.
- Encourage students to include information on the ‘science behind the story’ in their presentations. Ask students to be prepared to explain why and how the “innovation” is reducing emissions or increasing productivity in each case.
Ask students to share their presentations with the class.
Ask the students questions such as:
- What are the challenges for livestock producers in Australia in terms of balancing production and sustainability?
- How do livestock producers use science to produce food and fibre sustainably?
Additional information about current research projects investigating ways to reduce methane emissions in livestock production can be found on the MLA National Livestock Methane Program webpage.
Links to the Australian curriculum:
- People use science understanding and skills in their occupations and these have influenced the development of practices in areas of human activity (ACSHE136)
- Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge (ACSIS139)
- Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions based on evidence (ACSIS145)
- Communicate ideas, findings and evidence based solutions to problems using scientific language, and representations, using digital technologies as appropriate (ACSIS148)