The Challenge of Feeding the World Sustainably: Summary of the US-UK Scientific Forum on Sustainable Agriculture (2021)

The surface of the Earth has been transformed by agriculture. Cropland and pastureland cover more than one-third of the Earth’s ice-free surface. Of the water withdrawn from rivers, lakes, and aquifers, 70 percent goes to agriculture. The global food system feeds a world population of nearly 8 billion people, which is a remarkable achievement. Yet, more than 800 million people worldwide remain malnourished, and more than 2 billion adults and children are overweight or obese, in part because of a worldwide trend toward eating more processed foods and higher quantities of salt, sugar, and fat.

Agriculture’s extensive use of the Earth’s land and water has already had many deleterious effects on the environment and on biodiversity. Inputs to agriculture in the form of fertilizers, pesticides, and the mechanization of farming have produced higher yields but also have polluted the air, water, and soil. The expansion of agriculture has placed pressures on wild habitats and fisheries. Greenhouse gases from agriculture are contributing to higher temperatures and changing precipitation patterns, which have further stressed many plant and animal species.

Under a business-as-usual scenario, the deleterious effects of agriculture on the environment and on biodiversity will continue to increase. Higher levels of food production will require more fertilizer, pesticides, and irrigation and more extensive resource extraction from the land and sea. Growing populations and increased demand will exert pressures to convert more wildland to cropland. Such an approach would bring more air and water pollution, increases in greenhouse gas emissions, greater degradation and erosion of soils, greater threats to biodiversity, and intensified competition for land and other resource inputs. Given the already substantial effects of agriculture on biodiversity and the environment, such a future is not sustainable.

Many deliberative levers of change are available to transition agriculture to sustainability, including increased agricultural efficiency and yields, smarter land use, better use of markets and trade, reduction of waste, and shifts in diets. These levers of change often have multiple benefits. For example, many of the foods associated with a higher risk of chronic diseases like diabetes and heart disease, such as red meat and highly processed foods, also have the highest environmental impacts. Eating less of these foods and more locally produced fruits, vegetables, legumes, and nuts would reduce greenhouse gas emissions while also reducing the number of years of life lost to diet-related diseases. Similarly, reduction of the 25 to 30 percent of all food produced that is lost or wasted would mitigate environmental harms while enhancing food security and health.

Many ongoing and potential developments in science and technology could contribute to sustainability. An approach known as precision agriculture based on extensive data gathering, analysis, and use offers great potential to improve yields, reduce costs, and minimize environmental damage. Genetic technologies and other advanced biotechnologies could yield crops and livestock resistant to high temperatures and drought, protect against new and emerging pests and disease, increase efficiency in water use, improve nutritional value in foods, and reduce fertilizer use. Technologies such as robotics, artificial intelligence, process engineering, and synthetic biology could come together to shift the paradigm from “food produced by agriculture” to “food produced by manufacturing.” The social sciences could also foster sustainability—for example, through interdisciplinary assessments of incentives and preferences.

Policy actions will be needed to move the world not only toward sustainable agriculture but also toward a much broader sustainable global food system. A wide range of policy levers exists to overcome barriers to change, including incentives, regulation, and the establishment of new governance frameworks. At the same time, researchers will continue to investigate the food system and sustainability and how best to implement new knowledge in policy. Incremental steps may not be enough to produce the needed change. When dramatic change becomes possible, researchers and policy makers will need to be prepared with solutions that can be implemented quickly.

Sustainable agriculture will be characterized by healthy ecosystems and healthy diets that ensure resilience to climate change, economic security, social inclusion, and human well-being. A clear, long-term strategy for what needs to be achieved would provide policy actors and food systems with both direction and coherence. A coalition of national and international organizations, perhaps through an ongoing forum on sustainable agriculture, could promote both the research that is needed and the translation of this research into evidence-based policies.