Sustainable and circular bioeconomy for food systems transformation

Waste to Gold? Bioeconomy innovations for green cities


Gilles Martin and Hervé Levite sit down to talk to the FAO Bioeconomy team about FAO's Green Cities Initiative and how sustainable bioeconomy applications can help to transform urban agrifood systems.

Why is FAO interested in cities?

Our world is becoming increasingly urbanized, a phenomenon that is particularly evident in Sub-Saharan Africa, and to a lesser extent in South Asia and Melanesia. In addition to this rapid demographic change, cities from the global south are facing the impacts of multiple other challenges, including climate change and economic turmoil. These combined challenges massively increase the vulnerability of cities, at a time when they also need to reduce their environmental footprint, waste, greenhouse gas emissions, and energy consumption.

But there is an upside: cities are great solution centres to build a sustainable and greener future! They can enhance ecosystem services to provide cleaner air, temperature cooling, biodiversity conservation, and improved water management, thereby contributing to the UN Decade on Ecosystem Restoration, which FAO co-leads with the UN Environment Programme. Cities can also help us transform our agrifood systems to ensure healthy and nutritious diets for all, while boosting livelihoods and circular economy principles.

What is the Green Cities Initiative?

The FAO Green Cities Initiative (GCI) focuses on improving the urban environment, strengthening urban-rural linkages and the resilience of urban systems, services and populations to external shocks. Building on the experience, expertise and networks that FAO has gathered in more than 30 years working on urban areas, the GCI aims to improve the well-being of urban dwellers, particularly the most vulnerable.

The GCI is truly innovative in encouraging local governments to adopt an integrated approach on agriculture, forestry and food systems in urban policy, planning and actions. The key principles of FAO support are: setting up inclusive local governance; adopting systems thinking (based on multi-sectoral, multi-level and multi-stakeholder approaches); and linking rural and urban areas.

Cities can use many levers (regulation, public procurements and investments, incentives and public–private partnerships, awareness raising and education) and entry points (such as parks, peri-urban forestry, wet markets, school canteens, local food supply chain, waste management, etc.). By implementing activities in these areas of work, cities can become solution providers in reducing their ecological footprint and improving food security and nutrition, public health, and resilience.

FAO’s objective is to support 100 green cities by 2023, and up to 1 000 by 2030.

How can a sustainable and circular bioeconomy framework support the aims of the GCI?

Bioeconomy, which harnesses the potential of biological resources, has been an ally of cities for a lot longer than most people realise. For example, the ancient Romans were already using microbes and plants to clean the sewers of Rome over 2 000 years ago!

But times change and so do demands. Cities now account for 70 percent of the world’s food supply. This means huge pressure on cities to provide innovative and sustainable solutions throughout agrifood systems. In this regard, bioeconomy can help cities in many ways, including:

  • Closing the loop of nutrients and carbon contained in food, with a circular economy approach, to produce fertilizer, livestock feed and new molecules from food waste, human sludge and agrifood processing by-products;
  • Restoring green, blue and brown ecosystems – bioeconomy can help restore polluted and degraded urban areas; clean and sanitize contaminated air, soils, and water sources from various urban and industrial pollutants; and strengthen resilience of ecosystems to prevent flood damage;
  • Supporting food production in unfriendly environments for farming with aquaponics and vertical farming; and
  • Producing renewable energy from biomass sources, in particular waste produced in cities.

Can you give examples of good bioeconomy practices that could be adopted across the cities in the GCI?

Let’s look at food waste recovery, where FAO supports a number of cities. For instance, the city of Abidjan, Côte d'Ivoire, will collect food waste from markets to produce larvae aimed at feeding local poultry and fertilizing local crop fields. Meanwhile, Yaoundé, Cameroon, plans to close the loop from the household bin to urban garden by producing compost and vegetables.

But there are many other innovative bioeconomy solutions that could be used across GCI cities. To name just a few: treating polluted air with microalgae; using bio-based and biodegradable plastics to combat plastic pollution; recovering wastewater from food processing, thereby reducing urban pollution while extracting precious nutrients; restoring degraded soil to provide green public spaces or community gardens; systematically recovering organic waste (food waste and human sludge) for energy, fertilizer and animal feed.

How is FAO supporting the adoption of such practices?

FAO is working to convince local governments about the benefits sustainable bioeconomy applications can provide for their cities, framed around a compelling economic argument: avoiding costs related to wasteful and polluting practices, and getting multifaceted returns from more responsible ones.

Sustainable and circular bioeconomy can help restore ecosystems, increase food security and nutrition, and provide new economic opportunities, thus contributing to increased resilience of urban dwellers to climate change, food crises, economic shocks and other challenges.

FAO provides technical assistance and knowledge to cities on the potential of a sustainable and circular bioeconomy model to provide transformative solutions – in reality, there are many bioeconomies, so solutions should be adapted to local contexts and needs, rather than one-size-fits-all. In addition, FAO helps cities in adopting systems thinking, aided for instance by sustainable and circular bioeconomy principles which can help support agrifood systems transformation where diverse stakeholders work together in unison.

Finally, FAO plays a key role in connecting cities with local academia on the one hand, and with the national governments on the other, so that the scientific and political environments are in tune and can enable and speed up changes for a better world.


The Green Cities Initiative celebrates its second anniversary with an event on 2 November from 14:00 to 15:30 CET - Please register here to participate online in this event.


Photo credit: Gilles Martin – Karité butter manufacturing production in Korogho, Côte d'Ivoire 2022


FAO Green Cities Initiative

FAO Sustainable and Circular Bioeconomy

Aspirational principles and criteria for a sustainable bioeconomy