The influence of soil substrate quality on the effectiveness of roof landscaping is being investigated jointly by the Southern Federal University (SFedU) and the P. Lumumba Peoples' Friendship University of Russia (RUDN University) with the support of the Russian Science Foundation (RSF).

Scientists from the SFedU Academy of Biology and Biotechnology have started implementing their part of the project to assess and model carbon, water and heat fluxes in the Green Roofs ecosystem in Rostov-on-Don, in the SFedU Botanical Garden.

Professor Sergey Gorbov, Head of the Department of Botany of the Academy of Biology and Biotechnology  SFedU, Head of the Biogeochemistry Research Laboratory, said that the project is long-term in nature.

"A specialized hospital was built on the basis of the SFedU Botanical Garden, which includes models of green roof sections with soil structures of various compositions, as well as a system of minilimeters (containers filled with soil to study the transfer of water and other substances in the soil). One of the key objectives of the Green roofs study is to analyze their role in improving ecosystem services and mitigating the effects of climate change," said Sergey Gorbov.

In total, during the project implementation, it is planned to compare different types of substrates for roof landscaping in three cities located in contrasting climatic regions: Moscow, Rostov-on-Don and Yekaterinburg.

"The soil structures were created taking into account a combination of organic and mineral components that optimize the growth and development of a fairly narrow range of plants that can survive in high temperatures in Southern Russia and, as a result, ensure the stability of an artificially created ecosystem.  It is the right choice of substrate for the root layer that is an important aspect that has a direct impact on water retention, stable development of root systems and the functioning of microbial communities in the soil-plant-atmosphere system," explained Sergey Gorbov.

The scientist noted that the green roof modeling facility in the SFedU Botanical Garden is well equipped from a technical point of view. It will not only regularly monitor the temperature and humidity of the root layer, but also control the point supply of irrigation moisture due to the created automatic irrigation system, which includes a controller, specialized drip irrigation tubes and an atmospheric moisture monitoring sensor.

The hospital was established in December 2024 and at the moment the soil substrates are undergoing natural stabilization and shrinkage, which is facilitated by winter precipitation. Planting is scheduled for March 2025, and the final stage will be the installation of drip irrigation for each individual plant.

"The technologies being developed to create a green roof system will help improve the microclimate in cities, providing thermal insulation of buildings and reducing temperature stress in the summer. Moreover, "green roofs" help in managing the carbon balance by absorbing carbon dioxide and fixing carbon in organic matter. This is especially important for solving the problem of carbon neutrality of cities. A comparative analysis of different types of substrates in contrasting climatic zones will allow us to recommend the most effective materials for creating "green roofs" in different regions of Russia," concluded Sergey Gorbov.

"Green roofs" are becoming one of the most promising solutions for improving urban ecology and increasing resilience to climate change. They contribute to increasing the bio-productivity of the urban ecosystem, improving air quality and reducing the load on urban drains.

The project, which is being implemented on the territory of the SFedU Botanical Garden and in other cities, demonstrates the importance of integrating nature into the urban environment and allows laying the foundations for optimizing green infrastructure in various climatic conditions.