Accumulation of nickel in red clover

Abstract

Red clover (Trifoilum pratense L.) is considered as one of the most important legumes, and today is the second most important, after alfalfa. Production of high-quality feed from red clover may be affected, among other things, the increased concentration of heavy metals in some agricultural areas, primarily due to anthropogenic influences. The aim of this study was to determine the level of nickel in red clover grown on soils with different content of nickel, in order to obtain information on safety of these nutrients. The examination was conducted on four types of soil: chernozem, vertisol, eutric cambisol and humofluvisol. Sampling of soil and plant material was carried out during May 2011, in the second year of red clover production. The total content of nickel in soil samples, at a depth 0.30 cm, was in the range 3.36-129.67 mg/kg. Maximum permitted level of nickel in soil is 50 mg/kg. The content of nickel in red clover was in the range 0,41- 6,87 mg/kg, which is below the critical and toxic concentrations to plants. It was concluded that the accumulation of heavy metals in plants did not depend only on the total content in soil, but also the affinity of the plant, and individual and interactive effects of various soil properties. It is necessary to further control of nickel in contaminated area, in order to prevent his entry into the food chain and provide safety food.