Key messages
Soil sealing is defined as the permanent covering of the soil surface with impervious materials such as concrete or asphalt, tar seal, and buildings or other structures that cannot be easily removed. It leads to the loss of soil functions and ecosystem services.
Healthy soils are key to cooler, greener, safer and healthier cities
Sealed urban soils trap heat, worsen floods, and increase energy demand for air cooling. With two-thirds of people expected to live in cities by 2050, healthy urban soils and diverse vegetation are vital to cool cities, store carbon, absorb water, support biodiversity and improve climate resilience.
Living soils make cities more resilient
Urban soil sealing, pollution and fragmentation are affecting soil productivity and biodiversity, home to nearly 59% of Earth’s species. Protecting living soils sustains soil productivity, nutrient recycling and water filtration, and pollinators while supporting green spaces and strengthening resilience in urban environments.
Restoration of urban soils makes cities greener and healthier
Traffic, industries, untreated wastewater and solid waste lead to soils pollution in urban and peri-urban areas, threatening environment and peoples’ health.
Identifying, managing and restoring these soils can prevent and reduce illnesses, such as cancer and support safe urban and peri-urban agriculture and food, gardens and green spaces.
Urban expansion is consuming fertile peri-urban soils
By 2030, urban expansion could convert up to 2.4% of global cropland , much of its fertile peri‑urban land, potentially threatening 3–4% of worldwide food production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average.
Protecting these croplands through integrated land use and urban planning, growth boundaries, compact urban growth, and agrifood food system integration is vital to safeguard soils, secure food, and build sustainable cities.
Sustaining soil health in urban and peri-urban agriculture supports resilient agrifood systems
Practicing urban agriculture on well managed and healthy soils supports food security, nutrition and livelihoods, producing up to 10% of global vegetables, legumes and tubers and is an integral part of the urban socio-economic, ecological system and One-Health.
Greening cities improve health and well-being
Healthy and well-managed green spaces not only provide space for recreation but also support human health and well-being, as exposure to living soils and their microbiomes helps foster immune system development, especially in children.
Organic urban waste can be turned into soil wealth
Waste management is a major issue in cities, which produce about 70% of global municipal waste, with agricultural residues, organic waste, and roughly 20% of food making up most of it. When safely processed into compost, biochar, biowaste via black soldier fly, or used with perennials, this waste can return nutrients to urban soils, support farming and green spaces and turn cities into climate allies.
Urban soil is the hidden infrastructure of cities
The lack of recognition of the benefits provided by healthy urban soils leave the cities more vulnerable to floods, heat and pollution. Investing in healthy soils is a cost-effective way to save money, protect health and strengthen urban systems.
Soils in rural areas feed urban populations
Over 80% of the world’s food comes from family farmers who depend on healthy soils. As two-thirds of people are expected to live in cities by 2050, soils in rural areas remain essential to feed urban populations, sustain farmers’ livelihoods and strengthen global food security.
Soils are the hidden shield protecting cities
Healthy soils quietly defend cities from floods, landslides and erosion. By holding tens of millimeters of rainfall in the root zone, well-managed soils act as an Ecosystem-based Solution that reduces runoff, prevents erosion, lowers disaster risks to urban infrastructure and boosts climate resilience.