What does maths have to do with methane? Quite a lot, it turns out, with a research project combining the disciplines of biology and mathematics—funded by the New Zealand Agricultural Greenhouse Gas Research Centre—set to boost scientific knowledge of rumen systems and how to mitigate greenhouse gases. 
Yuancheng (James) Wang is graduating from Massey University this month with a PhD in mathematics. His multidisciplinary thesis saw him apply his mathematical knowledge to a topic that was entirely new to him: rumen microbiology. 
“For my project I developed a mathematical model that describes the interactions between microbes in the rumen and their food source,” explains James. “My model was also able to take into account the impact of the rumen environment on those interactions, which existing models designed to estimate methane production did not consider.” 
He says the results provided by his mathematical model were consistent with biological expectations, and the model could be expanded to include other factors influencing methane production, such as feeding level and frequency.
While James’ project focused on methane-producing microbes (methanogens), he says his model will be able to be used in conjunction with models describing other parts of the rumen system, which will provide the full picture of rumen function.
James says there are real benefits of applying mathematical modelling to biological systems. “Modelling means you can explore interactions that occur in the rumen system in ways you cannot do in experiments, and you can test your knowledge to uncover any gaps,” he says. “It’s also very cost-effective as it allows you to perform multiple experiments to understand what might happen in rumen systems, before designing and carrying out much more expensive animal trials.”
His PhD was supervised by Drs Peter Janssen and David Pacheco from AgResearch, who provided guidance on the how the rumen functions, along with Dr Tammy Lynch and Associate Professor Bruce Van Brunt from Massey’s Institute of Fundamental Science who supervised the mathematical component of the research. 
James says he never thought his background in mathematics would see him end up working in agricultural science.
“I’ve always been aware that mathematics can be applied to virtually any discipline, and it just happened that I got into this one which I’ve found extremely interesting,” he says. “I’ve really enjoyed learning about greenhouse gases—at the moment it’s a very critical topic for New Zealand, so it’s been great to be at the forefront of this science to help boost the knowledge a little.”
His work is currently being prepared for publication in a science journal in the near future.
James has moved back to Qingdao, China, to look for work and to be closer to family after more than a decade away from home. “I’ll certainly miss New Zealand though, and will always be grateful for the support provided by the NZAGRC for my project.”
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NZAGRC-PGGRC methane research programme