Металлы и металлоиды в донных отложениях водоемов восточной части Москвы

The chemical composition (concentrations of As, Ba, Be, Bi, Cd, Co, Cr, Cs, Cu, Fe, Ga, Hf, Li, Mn, Mo, Nb, Ni, Pb, Rb, Sb, Sn, Sr, Ta, Te, Th, Ti, Tl, U, V, W, Zn and Zr) and physicochemical properties of bottom sediments of the Kosino lakes and artificial ponds (Bolshoy Dvortsovy, Vladimirsky, Nizhny Ivanovsky, Severny Vykhinsky, Novogireevsky, Suzdalsky, Olkhovy, Vostochny Terletsky and Zapadny Terletsky) in the eastern part of Moscow were studied. Bottom sediments with coarse grain size, neutral pH level (7,2) and average organic matter content of 3,6% are common within the area of study. As compared with the background sod-podzolic soils of Meshchera lowland the bottom deposits accumulate Pb6,2, Sb6,1, W6,0, Zn4,6, Cd3,5, Te3,2, Fe2,9, As2,8, Rb2,5, Li2,5, Zr2,5 (numbers means background excess, times). Bottom sediments of Vladimirsky and Severny Vykhinsky ponds are the most contaminated; the first of them is located within the recreation zone surrounded by the Prozhektor industrial area and the Entuziastov highway, while the second one lies near the junction of the Kosino highway and the Moscow ring road. The following pollutants are of high priority: Sb, W, Pb, Zn, Cd, As and Te. The estimated permissible concentrations (EPC) for soils are exceeded in the bottom sediments of Vladimirsky, Severny Vykhinsky, Novogireevsky ponds and the Chernoe Lake for Pb by 18 times, Zn – 9,8, As – 9, Cd – 4,4, Cu – 3,3, Ni – 2, Sb – up to 1,6 times. Less dangerous levels of pollution are typical for the Svyatoe Lake and the Olkhovy Pond, where the EPC of As, Zn, Ni and Cd are exceeded up to 3 times. In comparison with other mineral components of urban landscapes (soils, road dust and dust in the snow cover) bottom sediments accumulate Sb and Pb, indicating their inflow with transport emissions and further migration to the inferior landscape positions.