The impact of the transport and road complex on heavy metal pollution of soils and plants

Abstract

This work aims to analyze heavy metals (HM) in soils and plants of the Balashikha, Moscow region. The authors studied HM content in soil and plant organs of Caragana arborescens and Taraxacum officinale depending on the distance of a motorway. The article shows the relationship between the concentration of HM in the soil and its content in plants. The authors also revealed the peculiarities of accumulation of some heavy metals - cadmium, lead, zinc and copper - in vegetative and generative organs of the studied plants. The authors noted the highest concentration of all heavy metals in dandelion growing near a motorway. According to the share in the total content of the determining elements, the metals can be arranged in the following order: Zn> Pb> Cu> Cd. The authors also observe a different pattern: Zn> Cu> Pb> Cd in soils with less pollution, i.e. in plants located at a 3000 m from the motorway. It has been observed that with a length of 3000 m from the highway compared to the 5 m zone of the road. There is a 1.13 times reduction in lead, 1.74 times reduction in cadmium, 1.89 times reduction in zinc and 1.66 times reduction in copper content in the soil and plants. The analysis shows that the studied plants can be used as bio-indicators of pollution of the biota of large cities. The most hazardous elements are cadmium and lead, which belong to the first hazard class, found in the atmosphere and ecosystems of cities, which is connected with intensive vehicular traffic. On working days, the traffic intensity in the morning hours (08.00-09.00) was 2500 cars and in the evening hours (18.00-19.00) 3000 cars (federal road M7 “Volga”).