摘要:Many
authors have studied cadmium concentrations in tobacco leaves. However, crops
such as tobacco store Cd mainly in their leaves and these are for human
consumption. The objective of this study is to establish the
cadmium levels present in each of the soils fractions throughout the growing
period of tobacco plants, and to examine the influence of these fractions on
the total content cadmium in dried leaves. The field select is situated near ofGranadacity
(soils from Vega de Granada) loamy
calcareous thermic typic Xerorthent. The plant (Nicotiana tabacum, cvs.
RJ36 variety), and the soil dedicated to the
tobacco crop were contaminated with a fixed amount of Cd (100 mg/kg of CdCl2)
in the proximity of the root influence area. The contents of Cd are analysed in channel waters, in different soil
fractions and dried tobacco leaves (mg/kg)
with the different treatments. In conclusion, the water for irrigation is not a
contamination risk for the soil even when user over lengthy periods of time. The fraction presenting higher average values is the one of Cd bound to CaCO3 with 0.161 ppm, and the Cd
bioavailable fractions is second in importance, and propose a Cd content sequence in fractions, higher to lower: Cd-Carbonates > Cd-Bioavailable > Cd-Organically bound > Cd-Exchangeable > Cd-Soluble.