It’s been a cruel summer. The pandemic continues to rage, while large parts of the world are on fire. Last week, a major UN report warned that time is running out to keep global warming within manageable (though still crisis-inducing) limits.
Yet in the face of these threats, research continues to offer innovative ways to rethink humanity’s relationship with the natural world, and potentially avoid the worst impacts of the damage that “business as usual” has caused. Case in point: a research paper, published in Nature Food on the same day as the IPCC report, proposes developing a “circular bioeconomy,” which the authors say could address the conjoined challenges of biodiversity decline and climate change. The answer, they say, lies in the way we use biomass.
Biomass describes any organic material that comes from plants and animals. From vegetables and meat for human and animal consumption, to raw materials for clothing, to crops and matter used to create fuels, we’re reliant on it. But the way we use biomass is extremely extractive: it relies primarily on harvesting virgin, wild or purpose-grown material to be consumed. This leads directly to deforestation, water and soil pollution, soil nutrient depletion, droughts, species loss and a whole host of other harms.
In the view of researchers at Wageningen University and Research in the Netherlands, this has to change.
“The less biomass we harvest from the biosphere and the more circular and regenerative our biomass production systems, the lower the impact will be on biodiversity,” study author Abigail Muscat told me. “This is because we are lowering the need to exploit natural ecosystems and enhancing biodiversity in the managed or agricultural ecosystems like aquaculture, fisheries and forestry.”
Biomass makes up about 25% of the 100 billion tons of material that humans consume every year, but the capacity of organic matter to combat harmful impacts and contribute to life on Earth makes it exceptionally valuable. Advocates of the circular bioeconomy, such as HRH the Prince of Wales, say that radically changing how we consume that biomass will help counter the long list of environmental harms previously mentioned.
On the climate front, circularity cuts emissions by conserving resources, reducing the need for artificial fertilizers and making use of organic sources of energy, such as biogas from waste. A circular bioeconomy would also help nations adapt to the changing climate by, for example, helping to preserve natural coastal defences such as mangrove swamps.
Many of these relationships are well documented, and overlap with the “nature-based solutions” approaches covered previously in this column.
Achieving the researchers’ vision, however, will require an altogether new approach to consumption.
“The circular bioeconomy does not mean that we cut and paste our current economy and make it bio-based,” Muscat said. “This would probably lead to more deforestation, more greenhouse gas emissions. It’s really about taking stock of the part of the economy that’s bio-based and using it better.”
To help people design such systems, Muscat and her fellow authors have drawn up five principles to apply to how biomass is used. These are:
Safeguard: conserving and regenerating ecosystems by, for example, preventing deforestation and the use of diverse crop rotations which improve soil health.
Avoid: by stopping the use of non-essential bio-based products, such as the squandering of resources by the “fast fashion” industry.
Prioritize: by using biomass principally for the most important human needs, such as food and pharmaceuticals.
Recycle: for example by making better use of human and animal waste in agriculture, and using human food byproducts for animal feed.
Entropy: using less energy by working with instead of against nature. Examples of such systems include closed-loop multispecies aquaculture, where the waste produced by one species of fish is used by another species for food.
One example of a biomass-friendly process that meets all five principles is to feed livestock only with foods that humans don’t eat. Presently, one third of cereals grown globally are fed to livestock, and a third of arable land is used to produce animal feed. Researchers say this is unnecessarily wasteful. In addition to encouraging people to eat less meat, they say, utilizing grazing land that isn’t suitable for crop production, as well as feeding livestock with feed from waste created by the production of human food, such as bran and whey, can help eliminate food “competition” between humans and domestic animals. Among many other benefits, research suggests that compared with “business as usual” scenarios, such a strategy would lead to 18% less arable land being used, 36% less non-renewable energy being expended, 22% less pesticide use, and 21% less fresh water being consumed.
Biomass for fuel also offers a win-win solution to the problems of greenhouse gas emissions and resource depletion—but only when that biomass comes from waste (and, importantly, not from crops grown specifically to turn into fuels like bioethanol). “When biogas is powered by food wastes and slurry rather than by maize and grass, it can lead to a 14% reduction in global warming potential and 67% in resource depletion,” Muscat said.
A detail of the Bosco Verticale residential towers in Milan. Building a circular bioeconomy would ... [+]
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The same principles should also be applied to urban environments, the researchers say. They envisage cities doing their part in “nutrient cycling” through the development of urban community gardens and farms, green walls and green roofs, rain gardens, and increased parks and trees that enable better cooling and air quality. Increasing the use of timber for architecture in cities could help act as a carbon sink. Meanwhile, water can be conserved through the use of rainwater and water management systems that reuse graywater from sinks and dishwashers for toilet flushing and irrigation. Smart toilets that use less water while separating types of human waste can enable municipal sewage facilities to generate compost and biogas.
For a detailed illustration of what a circular bioeconomy might look like, this example, produced in 2020 by a team of Dutch farmers, agricultural representatives and scientists, envisages a complete “re-rooting” of the Netherlands’ food system by 2050. The vision set forth is unapologetically bold; a “fundamental shift” in how society approaches and consumes food. “This system will no longer be governed by the free market,” the authors write, instead being based on “an inclusive market system which recognises the value of public goods such as fresh air, clean water, healthy soil and diversity of species and landscapes.”
Critics could very easily dismiss such projects as utopian fantasy. But proponents, from Dutch farmers and scientists to Prince Charles, believe that such transformative change will be essential if human societies are to fully reckon with the twin climate and biodiversity crises.
What are the chances human society will be willing and able to retool the economy in such radical ways?
“I think if we are ambitious, we can make great progress in just five years,” Muscat told me. “However, this concept is still relatively new, it’s ambitious and I don’t even see enough political will for solutions that have been known for decades, such as renewables and agroecology. So certainly, one of the major challenges is political.”
On the other hand, she added, with the IPCC report fresh in everyone’s minds and extreme weather events gathering pace and ferocity, policymakers could find there is a growing public appetite for bold, provable strategies that offer multiple benefits.
“This summer was apocalyptic and scared many scientists. I hope it will scare politicians too,” she said.
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