Yield and heavy metal concentration of white cabbage [Brassica oleracea capitata] and beet [Beta bulgaris] cultivated in soil amended with river-sediment from Hanoi, Vietnam

The study was undertaken to examine effects of amendment of agricultural soil with river-sediment on the yield and heavy metal concentration of crops cultivated in it. Sediment was collected from the river in the industrialized and densely-populated area of Hanoi city and added to agricultural soil at the rates of 0, 10, 20, 30, 40 and 50%, followed by thorough mixing. White cabbage and beet were cultivated in pots at Hanoi Agricultural University. After harvest edible parts (leaf for white cabbage and root for beet) of both crops were weighed. The yield was highest at the soil with 30% addition of the sediment for both crops. The total concentration of heavy metals was higher for white cabbage than for beet and was not parallel with the percentage of sediment in the soil. Concentrations of Cd and Pb in white cabbage and Cd in beet were over the Vietnam standard for maximum permissible heavy metal concentration in vegetables