Assessing the Potential of Urban Trees to Accumulate Potentially Toxic Elements: A Network Approach

Abstract

In urbanized areas, mitigating the negative effects of pollutants from various anthropogenic sources is one of the most important issues in planning urban functioning and development. In this sense, urban vegetation plays one of the most important roles. The aim of this study was to investigate the performance of network analysis (NA) as a novel and potential method for determining different associations between potentially toxic elements (PTEs) in leaves of urban trees, their accumulation capacity and ecophysiological response to different types of pollution in urban environments. The results of NA showed that there is no association between elements in species that have lower or higher efficiency in uptake of PTEs, leading to the conclusion that the elements do not depend on mutual association but on accumulation itself. It was also found that there are differences in the content of photosynthetic pigments and carotenoids among the studied species, but these differences are not reflected in the values of the photosynthetic efficiency parameters. Overall, the studied species have good ecophysiological potential for growth and existence in the urban environment, despite the varying ability to accumulate elements and the different associations between them. This is the first study to investigate the interactions between PTEs in leaves of urban tree species using NA and provides a good basis for future research under different environmental conditions.