Formation and assessment of ecological risks of urban landscapes in industrial cities of Belarus

Abstract

The problems of the formation of hazardous natural and man-made processes in industrial cities, contributing to the emergence of environmental risks, are presented. To date, an extensive literary material has been accumulated on this problem, concerning the causes of its occurrence, analysis of the patterns of development, and the possibilities of managing risks, including the environmental ones. It has been established that the list of reasons for the formation of risks in cities lacks one of the most important factors that we have discovered – the structure of urban landscapes, which are quite large objects of urban development. To identify the role of these objects in the formation of environmental risks, the cities of Orsha and Pinsk were selected. These cities were laid down almost simultaneously at the beginning of the 11th century, but they have a different history of development. Maps of urban landscapes of cities were compiled, geochemical studies of their soil cover were carried out, geochemical and thermal anomalies of the surface were revealed, the volumes of ecosystem services (carbon absorption) by green spaces were calculated. It was found that urban landscapes perform various functions in the system of environmental risks: some of them contribute to the development of hazardous processes, others – to mitigate them. So, soil pollution with heavy metals (with an excess of the content of Pb, Cr and Cu over the MPC by 1.2–5.6 times in Pinsk), the strongest heating of the surface (8–16 °C higher than the air temperature in Pinsk and Orsha) and low carbon deposition (100–500 t per year) are typical for urban landscapes of the historical center, urban landscapes with a predominance of industrial buildings, urban landscapes for complex residential multi-storey, public and industrial buildings. Urban landscapes, in the structure of which there are elements of landscape and recreational areas of public use (parks, forest parks, squares), as well as agricultural lands and water bodies, are characterised by a low content of heavy metals in soils (below the MPC in Pinsk, below the background in Orsha), low surface temperature (2–3 °C higher than the air temperature), high volume of carbon deposition (2.6–2.8 thsd t per year). An assessment of the probability of risks associated with the described processes was carried out, which helped to find out that they correspond to the categories of «acceptable» and «neglected», options for risk management were proposed.