Uptake of Cd and Ni by spinach, spinacea oleracea (L.) from polluted soil under field conditions as affected by salt water irrigation

Abstract

Both heavy metal pollution and soil salinization are increasing in dry areas. Nevertheless, salinity-heavy metal interactions in soils and crops are not well understood. This work aimed at evaluating the effect of salt water irrigation on the uptake of Cd and Ni by spinach from a polluted soil under field conditions at the Nahda project site, northwest of Egypt. Microplots were irrigated either with water or with salt solution (0.8 g·for 9 weeks. Subsequently, the plants were harvested for root evaluation and plant as well as soil chemical analysis. Salt water irrigation stimulated root development and enhanced the extractability of Cd and Ni from soil as well as their uptake by spinach considerably. Possibly related interactions are discussed. The results suggest that the risk of leaching of heavy metals into surface waters and their transfer to the food chain in salt affected areas may be much greater than so far assumed.