Greenery's potential in combating air pollution is being explored. The CLAIRO project introduces innovative approaches

  • Lucie Dospivová
  • 05.09.2023
During the period spanning from 2018 to 2022, the University of Silesia in Opava, specifically its institute of Physics (FÚ SU), assumed a prominent role as a key contributor to the CLAIRO project under the Urban Innovative Actions program – a program known for endorsing Europe's most pioneering initiatives and bearing substantial prestige. The results of the research can significantly help to determine the optimal selection and placement of plant species across the Europian cities.

Vegetation in a role of air purifier

„Air pollution represents a significant enviromental challenge, extending beyond just the Moravian-Silesian Region. The CLAIRO project provides an inventive remedy, centering on the concept of strategically planting highly effective air-purifying vegetation,“ as described by Associate Professor Miloš Zapletal from the Institute of Physics in Opava, one of the main managers of the CLAIRO project.

This project focuses on developing innovative models of air pollutant capture by urban greenery using both pollution information and meteorological data. The research also includes the creation of an accessible online database of plants that are particularly effective at capturing air pollutants. From the proposed database, other interested parties will then learn what vegetation and what planting procedures to use in an effort to improve the environment.

The main phases of the CLAIRO project and their mutual connection. Source: Web projektu CLAIRO. The main phases of the CLAIRO project and their mutual connection. Source: Web projektu CLAIRO.

The right greenery for a natural filter

The CLAIRO project stands as a pioneering force, advocating the integration of green spaces to enhance air quality. Due to the complexity and technical nature of the project, it contributed to the development of a number of innovative practices that can be used relatively easily in cities across Europe.

The project's activities are structured into three distinct stages. In the initial phase of research, extensive measurements were conducted, yielding crucial data regarding the progression of air pollutant concentrations,“ explains Zapletal with the fact that, for this purpose, researchers from VŠB - Technical University in Ostrava installed measuring sensors at the place of planting greenery. The collection and analysis of data, conducted throughout all seasons and under diverse climatic conditions, played a pivotal role in the project's second phase. This phase involved the formulation of the greenery's structure and composition, a task expertly carried out by researchers from the Institute of Physics at the University of Silesia in Opava. „As al part of CLAIRO, nearly 500 trees and over 1,700 shrubs found their home in the two designated areas of Ostrava Radvanice and Ostrava Bartovice. Due to the relatively large number of plants and a rich diversity of species, these two sites were transformed into living laboratories, serving as testing grounds to evaluate the efficacy of greenery in enhancing air quality. The meticulous selection of these locations was driven by their role as tailored case studies," explains the scientist.

Methodology for evaluating the absorption of pollutants by plants

Researchers from the Institute of Physics in Opava designed and applied the methodology of planting greenery in an urban environment with regard to the capture airborne pollutants. They then equipped experts with knowledge who, in turn, pass on the acquired know-how to selected cities in the Czech Republic and the EU. They compiled illustrative examples of best practices for reducing pollutants through greenery and crafted a comprehensive strategy for disseminating this knowledge to cities and specialists. They also published professional articles based on project outputs, presented project results at international conferences, actively engaged in the management and organization of workshops for experts.

One of the specific outputs of the researchers from the Institute of Physics in Opava is a database of plants with a demonstrable effect on reducing air pollution. The database currently contains 185 woody plant species that are commonly found in European climates. „This database is intended to assist cities and municipalities in the careful selection of plants most suitable for planting in emissions-burdened environments,“ explains Zapletal, who also participated in the database creation. In the database, plants are categorized based on a range of characteristics, including the capacity of woody species to capture pollutants and withstand their detrimental effects.

The database's category overlays empower users to evaluate the similarities among various tree species concerning their requirements for growth conditions and resilience to industrial load. „The user of the database can propose mixtures of tree species with similar characteristics and select those plants that are most suitable for planting in a specific city or village with regard to air pollution. Greenery managers can also utilize the database as a valuable resource during their decision-making and planning processes,“ as Zapletal explains the immediate practical use of the database.

About the CLAIRO project

The CLAIRO project has been ongoing since 2018 and aims to systematically reduce air pollution by planting suitable greenery with a proven ability to absorb air pollutants from various sources. In 2022, as part of the Sustainable Development Goals (SDGs) Awards, the CLAIRO project achieved significant recognition, emerging as one of the top twenty semi-finalists from a pool of 326 projects. The competition annually awards projects that address various topics from the United Nations Sustainable Development Goals and have a concrete social impact. In 2023, the CLAIRO project is participating in the Adapterra Awards competition in five categories – open landscape, built-up areas, work environment and our home. CLAIRO was a research project led by a team of experts from the Institute of Physics of the University of Silesia in Opava, VSB - Technical University of Ostrava and the Palacký University in Olomouc. The Statutory City of Ostrava spearheaded the project, with collaborative support from the Moravian-Silesian Region, the SOBIC organization, and the Regional Association of Territorial Cooperation Těšín Silesia.

The results are available to the public via this website and also scientific paper. For more comprehensive details about the project, please refer to the previous press release.

Links and further information:

Contact information:

doc. Ing. Milos Zapletal, Dr.

Main investigator of the CLAIRO project at the Institute of Physics of Silesian university in Opava 
Telephone number: +420 737 067 897

Mgr. Petr Horalek

Spokeperson of all european projects at the Institute of Physics of Silesian university in Opava 
Telephone number: +420 732 826 853

prof. RNDr. Zdenek Stuchlik, CSc.

Director at the Institute of Physics of Silesian university in Opava
Telephone number: +420 553 684 240