Book with abstracts from the COST Action 0905 meeting in ... - UMB

THE IMPACT OF HEAVY METALS ON RED CLOVERS
Audronė Mikalajūnė, Giedrė Jasulaitytė
Department of Environmental Protection, Vilnius Gediminas Technical University,
Saulėtekio av. 11, LT – 10223, Vilnius – 40, Lithuania
E-mail: Audrone.Mikalajune@vgtu.lt
Keywords: heavy metals, red clovers Arimaičiai, soil pollution
Red clovers Arimaičiai have been chosen in this work for decontaminating soil from
heavy metals. These plants were grown under artificial laboratory conditions in soil which was
periodically contaminated with heavy metals.
Plastic pots of 7x25x11 cm with double bottoms were used for the experiment. 0.5 kg of
uncontaminated soil was put into each of the pots. Each pot with soil contained 10 g of seeds.
Uncontaminated soil was used for growing control plants. Seeds of plants were seeded to
uncontaminated soil and soil which was periodically contaminated with heavy metals. Since
humidity is the main factor conditioning the growth of plants and the necessary physiological
processes, grass plants were watered every 3 days. Control plants were watered with 100 ml of
ordinary water while plants grown in the periodically contaminated soil were watered with
100 ml of mixture of heavy metals. The maintained temperature was 22-24 0 C and the lighting
was natural. The experiment lasted six months.
Table 1. Heavy metals concentration in the soil
Cu mg/kg Cr mg/kg Zn mg/kg Pb mg/kg Mn mg/kg Ni mg/kg
90 100 300 100 1200 75
After permanent soil application with Cu, it was noticed that after six months Cu
concentration in soil was 3 times smaller than in the beginning of experiment, but in red
clovers there were 25 mg/kg of Cu. When Mn concentration in soil reached 1200 mg/kg, after
VI month red clovers had absorbed 30 % of it from soil, so it was noticed that concentration in
plant was 355 mg/kg of Mn. When Ni concentration in soil reached 75 mg/kg it was noticed
that after VI month red clovers absorbed 32 % of Ni from soil (24 mg/kg of Ni in red clovers
Arimaičiai). When Cr concentration in soil reached 100 mg/kg after VI month red clovers
sorbs 31 % of Cr (31 mg/kg in red clovers), and when Zn concentration in soil reached 300
mg/kg red clovers sorbs 17 % of Zn from the pollution soil (51 mg/kg in plant). When Pb
concentration in soil reached 100 mg/kg red clovers removed 23 % of Pb from the soil, so
there were 23 mg/kg of Pb in red clovers Arimaičiai.