Agronomische Maßnahmen zur Reduzierung der Cadmiumaufnahme bei Salat (Lactuca sativa L.)

Abstract

Some plants such as lettuce accumulate cadmium (Cd), one of the most harmful heavy metals, in vegetative parts even on soils with low total Cd. The objective of our investigations was to obtain information if agronomical treatments result in an increase or decrease of Cd soil availability or plant Cd uptake. It is necessary to investigate soil Cd availability and Cd uptake by plants separately. Using different levels of NPK fertilizer it was found that with an increase in the amount of fertilizer, there was an increase in Cd availability resulting in increased plant Cd uptake. The better plant growth with increasing fertilization resulted in a reduction of Cd plant concentration due to a dilution effect. NPK fertilizer and green manure increased soil Cd availability, whereas lime or compost decreased soil Cd availability. These effects were reflected by plant Cd uptake.

From the results of this investigation it can be concluded: (i) increasing fertilization may result in concurrent increase in plant Cd concentration, (ii) this accumulation can be prevented by liming and in particular by compost application. These results, however, may be soil-specific.