In this post, masters student Sophie Jane Tudge details her research into biofuels.
Carbon-neutral energy sounds like it is exactly what the world needs right now. With the UN Climate Change Conference (COP26) almost upon us, more people than ever are asking how we can halt climate change to protect our planet and, ultimately, ourselves. The greenhouse gas emissions from fossil fuels have led to many countries, including the UK, to make commitments to shift over to renewable energy sources. But renewable energy does not always mean that it is good for the environment. Let’s take a look at one growing form of renewable energy: biofuels.
What are biofuels?
Biofuels are a form of renewable energy. Biofuels come from plants that are either fermented to produce alcohol (bioethanol), or that have fats extracted (biodiesel). These compounds are then burned to produce energy. Some of the most popular and well-known biofuel crops are oil palm, soybean and maize, but there is a large variety of biofuel crops available worldwide.
Are biofuels good for the planet?
Biofuels reduce our dependence on fossil fuels, which is good for the environment. However, increased demand for biofuels drives agricultural expansion. When we have more agricultural land, we’re forcing all the other plants and animals that share this planet with us to either adapt to living in a man-made system, or be pushed out of that land to try to survive in the dwindling amount of natural habitat left. But how well can biodiversity – the variety of life on Earth – cope in biofuel plantations? Despite the availability of different biofuels, until recently, there was limited information on how growing different biofuel crops affects local biodiversity .
Our research into biofuel impacts on nature
During my master’s degree in Ecology, Evolution and Conservation Research at Imperial College London, I joined the PREDICTS team based at The Natural History Museum to carry out an independent research project. I used the PREDICTS database – a collection of biodiversity data from around the world – and data science techniques to investigate how local biodiversity differs in land that is used to grow different biofuel crops and compare the results to the biodiversity found in natural ecosystems and other human land uses, including pasture and urban areas. With the help of my supervisors Professor Andy Purvis and Dr Adriana De Palma, the results of my research are now available to the public.
Not all biofuel crops are made equal
We found that first-generation biofuel crops – the ones that contain oil, sugar or starch and are usually also grown for food – reduced the local species richness and total abundance of organisms by 37% and 49% compared to natural ecosystems. The worst first-generation biofuel crops for local biodiversity were soybean, wheat, maize and oil palm. It was clear that the impact of biofuels differed regionally – with the biggest declines in biodiversity in Asia and Central and South America. Biofuels also impacted different types of species differently. There are many alternative biofuel crops, including ‘second-generation’ non-food crops and lignocellulosic crops, which we found had, on average, less damaging impacts on local biodiversity.
So what biofuel crops should we grow?
When it comes to deciding what biofuel to use and where to plant it, we also have to take other factors into account, like whether it will impact endangered species. We also need to consider yield; if a crop has a higher yield, we’ll need to use less land – so even if it is more damaging for biodiversity on a hectare per hectare basis than another crop, it could be less damaging overall if the other crop needs more land to produce the same amount of energy.
I hope that my work inspires others to look further into the impacts of growing biofuel crops on biodiversity and ultimately leads to more sustainable land use that is compatible with conserving, and even enhancing, biodiversity.
By Sophie Jane Tudge