“Food in the Anthropocene represents one of the greatest health and environmental challenges of the 21st century,” begins the EAT-Lancet Commission’s 2019 report on healthy diets and sustainable food systems.

The nature of the challenge is well-known: how can we produce enough food to nourish a growing population with an increasing appetite for animal products, given finite land and limited resources? But that’s not all, this needs to be achieved whilst keeping global warming below 1.5 degrees, and protecting and restoring all life on our planet.

Much of the world’s food cultivation has shifted from small-scale, diverse farming systems to large-scale, industrial monocropping of staples such as wheat, maize, rice, soy and palm oil. The shift has some logic to it – simplifying, streamlining and upscaling systems to fill more bellies, faster, makes intuitive sense when people are starving.

But industrialized farming can have severe environmental impacts. Locally, these may take the form of forest and vegetation loss from land clearing, and pollution of waterways from animal waste and fertilizer runoff. Globally agriculture contributes to around a quarter of all greenhouse gas emissions and uses almost half of the world’s vegetated land. A landmark United Nations report this year warned of the 1 million species of plants and animals facing extinction, citing agricultural intensification and expansion as a significant cause.

What’s more, despite fulfilling basic energy needs, the more-homogenized diets delivered by industrial agriculture are not providing all of the micronutrients that we need to thrive. While proportionately fewer people in the world are going hungry than half a century ago, every country is affected by some form of malnutrition, and obesity rates have skyrocketed in both developed and developing countries.

“So there’s been much more interest recently in the nutritional value of food systems,” says World Agroforestry (ICRAF) and Scotland’s Rural College  (SRUC) scientist Ian Dawson. Dawson is lead author of a new review that explores how biodiversity can contribute to the sustainable intensification of food production. “In the study, we’re thinking about environmental sustainability, but also about what we might call dietary sustainability: the ability to produce a range and diversity of healthy foods.”

A WINDOW OF OPPORTUNITY

It’s an ironic truth that in many low- and middle-income tropical and sub-tropical regions, where people are often lacking in important nutrients, there are actually a wide range of biological resources – such as wild plants and pollinators – available. These have the potential to support more sustainable and nutritious food production, but they’re often at high risk of being lost as industrial food production expands.

To use these resources efficiently – and value them appropriately – farmers, development practitioners, funders and policymakers need to understand the contributions they make to production, and the opportunities and constraints for exploiting their functions further. “There may be only a limited time window to effectively “use” rather than permanently “lose” these valuable biological resources,” say the authors, “to support both sustainable agricultural intensification and healthy diets.”

As such, the review is something of a “call to action,” to ensure these resources are not lost before their true value is recognized and explored. Conducted by a group of scientists affiliated variously with ICRAF, the Center for International Forestry Research (CIFOR), SRUC, the University of East Anglia, Bioversity International and the Worldwide Fund for Nature (WWF-Singapore), the work explores the ways that crops interact with other forms of biodiversity. These include other crops, pollinators, natural vegetation such as trees, below-ground organisms such as microbes, livestock, and fish.

The scientists considered both the quantity and quality of food being produced within the farmed landscapes. The role of trees in providing habitat for pollinators “stood out as really crucial,” says Dawson. These pollination services “go to crops that are important from a nutritional perspective in human diets. A lot of fruit trees are insect-pollinated, for example.” There was also strong evidence for the role of leguminous trees and shrubs in enabling sustainable intensification, “because they fix nitrogen, which supports crop production,” he adds.

The review also showed that context is crucial: the impacts of biodiversity are often positive – but not always – so biodiversity-based intervention options must be tailored to the site at which they take place. “Farmers need to be able to access the knowledge to adopt systems appropriate for their land,” says Sarah Park from the University of East Anglia, another of its authors. They also need to know that doing so will be worth their while. “The global trend is still towards less diverse farming systems. So there are a lot of challenges around introducing more diverse systems, even if they’re more productive and/or more profitable. It’s often a knowledge cost,” says Park.

A PORTFOLIO APPROACH

In the review, the authors call for prompt action in bringing about a more holistic approach to food production, stating: “how land is used and the quality of the food it produces must be considered together.”

ICRAF’s recent work in East Africa provides one example of what this might look like. There, researchers have begun working to support farm diversification for healthier food availability in a number of locations in Ethiopia, Kenya and Uganda. They’re helping farmers to create ‘food tree and crop portfolios’, which complement the production of other crops by supplying important nutrients to farm families.

“The tree and crop foods that make up the portfolios are chosen by local people and researchers working together,” says Dawson of the work of his colleagues. “They consider the current diets of communities, the popularity of particular food trees, how easily they grow, the time of the year at which they produce food, and the nutrient composition of the foods provided.” Participatory, site-specific approaches like this one are likely to play an important role in feeding the world well today, and into the future, he concludes.

Related reading

Agricultural intensification has fed the world, but are we healthier?

Agricultural intensification, dietary diversity, and markets in the global food security narrative

Quality over quantity: changing diets and consumption

Changing landscapes: from forests to food

So long, and thanks for all the fish!

Integrating wild and agricultural biodiversity intensification – why we need both