Moss is emerging as a key ally for large cities in the fight against pollution and climate change. Capable of retaining up to 20 times its weight in water, it functions as a natural sponge on asphalt, absorbing heavy rains and filtering heavy metals and toxic particles from the air.
Researchers from Nottingham Trent University are experimenting with this system in Nottingham, demonstrating that bryophytes can alleviate the burden on sewer systems and improve environmental quality without the need for complex infrastructures.
Unique properties of bryophytes
Moss, being a non-vascular and rootless organism, absorbs water directly through its entire surface. This allows it to grow on concrete or asphalt, transforming impermeable surfaces into biological sponges that manage water passively.
Unlike grass, it does not require deep soils or constant maintenance, making it an efficient option for sustainable urban drainage.
Environmental benefits
- Water management: reduces flow to sewers during heavy rains, preventing floods.
- Air purification: filters heavy metals like lead, cadmium, and zinc, as well as fine particles PM2.5.
- Carbon sink: contributes to the capture of atmospheric pollutants.
- Urban safety: decreases the formation of puddles on streets and improves road safety.
According to the study cited by Muy Interesante, moss acts as a passive treatment plant, preventing pollutants from dispersing into the air or seeping into the subsoil.
Implementation challenges
The effectiveness of moss depends on local climatic conditions. In arid climates or those exposed to extreme heat, its permanence is limited and requires hydration systems or resistant species. This implies that its application must be adapted to each urban context.
Moreover, specialists warn that species selection is crucial: some moss varieties tolerate sun exposure and drought better, while others thrive in humid and shaded environments. Urban planning must consider these factors to ensure the system’s viability.
Application examples
European and Asian cities are already experimenting with moss-based green infrastructures. In Germany, vertical moss panels have been installed on avenues to reduce traffic pollution. In Japan, green roofs with moss are used to regulate temperature and improve the energy efficiency of buildings.
These experiences show that moss can be integrated into living walls, green roofs, and permeable pavements, expanding its impact beyond urban drainage.
Moss represents an innovative biotechnological solution to build more resilient and sustainable cities. Its ability to absorb water, filter pollutants, and function with minimal maintenance makes it a strategic resource to face the challenges of the 21st century.
Integrating moss into urban infrastructure not only improves water management and air quality but also promotes a model of ecological architecture that connects cities with natural processes. In a world increasingly affected by the climate crisis, this “green tapestry” could be the key to transforming cities into safer, healthier, and more adaptable spaces.
