ECOTOXICOLOGICAL CHARACTERISTICS OF THE GROUND SAMPLES OBTAINED FROM URBAN GREEN ZONES SITUATED IN KAZAN (RUSSIA)

Abstract

Public gardens and park zones are an important and widely visited component of urban spaces worldwide, however they can be polluted and even dangerous for humans and animals visiting them. The simplest way to screen the level of pollution of those green zones is to assess their ecological toxicity. In the present study, to assess the ecotoxicity of soil and ground samples obtained in 15 parks and public gardens in the city of Kazan (Russia) with 1 Mio citizens were investigated. Two elutriate assays with Ceriodaphnia affinis and Chlorella vulgaris and one contact assay with Bacillus pumilus were used in order to estimate the ecotoxicity of the samples. It was revealed that B. pumilus was less sensitive to the components present in ground samples from the green zones. Thus, the lowest toxicity of the undiluted sample was estimated to be 3.33% (sample Gorkiy Central Park of Culture and Leisure) and the highest � 27% (�Dubovyj kordon� public garden). For C. affinis, we managed to assess the toxicity without dilution step for 7 samples out of 15. For the other 8 samples, the additional dilution series was prepared, and the LID10 index was calculated. Thus, the LID10 index these samples for C.affinis ranged from 34 to 40, for Chl. vulgaris varied from 13 to 50. It should be noted that samples with the highest toxicity (revealed for at least one test object) were obtained from the parks that visually looked less clean and organized.