Ecotoxicological Assessment of Roadside Soils in Areas along Leningradskoe Highway Using Laboratory Phytotesting
Roadside soils along Leningradskoe Highway are ecotoxicologically assessed by the laboratory phytotest method based on two test cultures. The research was carried out along a 300-m-long transect established perpendicular to the highway. The toxicity of soils, determined according to inhibition of the growth parameters of Lepidium sativum L. (cress) and Hordeum vulgare L. (rye), has been revealed in the majority of the studied area and is characterized by a bimodal distribution: it is maximum at a distance of several meters from the highway (dangerously and moderately toxic soils), sharply decreases at a distance of 7 m from it, and gradually increases again towards the end of the studied zone (moderately toxic soils). The degree of phytotoxicity is differentiated depending on the test culture variant: H. vulgare was characterized by a lower sensitivity to pollutants and did not reveal toxicity in the 7–25 m zone from Leningradskoe Highway, while L. sativum revealed toxicity of soils throughout the investigated area. Among the analyzed test parameters, root and seedling length were the most sensitive to pollutants, while seed germination was uninformative.