There are two greatest municipal wastes landfills on the territory of Vilnius located in leisure zone with gardens situated in their neighbourhood and cows pasturing there. Though dangerous for health consequences of such activity were suspected but lack of real data determined indecisive position for radical limitation of some economic activity and land use there. The variety of plants on the territory of one of these objects enabled to analyse the possibility of technogenical biogeochemical accumulation of chemical elements. For this aim meadow grass was collected from 3 sites: a) at the top of municipal solid wastes landfill; b) at its foot; c) in conditional background environment; and Caucasian plums- from the following 3 sites: a) on the slope of the landfill;
b) in botanical gardens of Vilnius university; c) in out-of-town garden. At the same time soil was investigated in 3 levels of the landfill: 1) at the top; 2) on the slope; 3) at the foot; as well as in conditional background environment. Each investigated object was characterized by 16 parallel samples that were analysed for Ag, B, Ba, Co, Cr, Cu, Mn, Mo, Ni, P, Pb, Sn, Sr, V, Zn using DC Arc Emission Spectrometry.
The set of elements with anomalous concentrations in soils from the top of the landfill includes Cu (average technogeochemical loading index Iav in comparison with natural quantities in soils is 10), Ag(Iav=7.8), Zn(6.3), Cr(2.6), Pb(2.5), Sn(2.5), Mo(1.2), Ni(1.2), Sr(1.2). Iav of the other elements are close to 1. Total average multielement index of soil pollution Imulti is 27. The set of elements with anomalous concentrations in soils on the slope of the landfill includes Ag(Iav=29), Zn(25), Cu(11), Sn(4.3), Pb(4.0), Cr(2.0), Mo(1.9), Ni(1.6), B(1.2), Sr(1.2)and Imulti is 72. The set of elements with anomalous concentrations in soils at the foot of the landfill includes Sn(Iav= 66), Zn(32), Ag(28), Cu(26), Pb(12), Mo(6.1), Cr(3.4), Ni(3.2), P(1.9), Ba(1.5), Sr(1.4), B(1.3), Co(1.2)and Imulti is 172. It is natural that total level of contamination is increasing from the top of the landfill downward to its foot. It is clear because precipitation that is washing out toxic chemical elements during hydrolysis reactions has discharge places exactly at the bottom of the landfill.
Biogeochemical composition of grass growing in different places of the landfill is also different. The set of elements with anomalous concentrations in grass growing on the top of the landfill is the following: Zn(average biogeochemical accumulation in comparison with natural quantities in grass Iav=5.0), Mo(3.2), Cu(1.7), P(1.6), Ag(1.3). Total average multielement index of biogeochemical accumulation Imulti=9. The set of elements with anomalous concentrations in grass growing at the foot of the landfill includes Mo(Iav=9.4), V(6.7), Ag(6.5), Cu(4.2), Mn(3.5), Ni(2.4), Pb(2.3), Cr(1.9), B(1.9), Ba(1.3) and Imulti is 31. The sequence of the elements in both latter sets characterizing grass differs from two corresponding sets characterizing soil due to different biophylic accumulation properties of the elements. The increase of total quantities of the elements, however, is evident. Average geochemical accumulation coefficients that are showing the ratio of elements-pollutants in the pulp of the plums growing on the territory of the landfill to those growing in botanic gardens of Vilnius university and that are exceeding one are showing the possible influence of the landfill on fruit quality: Ag: 5.4, Cu: 4.5, Ni: 4.4, P: 1.8, Mn: 1.6, B: 1.5, Cr: 1.3, V: 1.2. The contents of Zn in the pulp of the plums is similar in both places and that of Pb and Mo is even lower on the territory of the landfill. The reason can be that botanic gardens is situated near large industrial district of Vilnius. The composition of plums in out-of-town garden is quite different. Pb concentration even 5 times and Zn: 1.8 times exceeds the corresponding concentrations in plums growing on the territory of the landfill. As the garden is located near the highway this fact can be explained by atmospheric contamination of motor transport. At the same time the quantity of B in the pulp of the
plums growing on the territory of the landfill 2 times, Cu: 1.8, Mo: 1.6, Ni: 1.3, Ag: 1.3, Cr: 1.1 times exceeds the quantities of corresponding elements in the pulp of the plums growing in out-of-town garden-plot.
In contaminated places biogeochemical accumulation of chemical elements is intensive. It has direct relationship not only with geochemical composition of ground but depends also on biophylic properties of the elements and probably on the level of air pollution. Agricultural activity should be limited in such areas.