Seasonal variations in the metal content of amenity grass and its use as an indicator of reclamation treatment performance

Abstract

An experiment was conducted to assess the efficiency of soil covering treatments as a management technique in the reclamation of land contaminated with metals. The performance of a range of depths and types of soil cover was evaluated over the growing season by observation of the metal content and growth rate of amenity grass established on the cover treatments. Difference in metal uptake rates were observed both between treatments and with respect to time of harvest; however, for most metal/treatment combinations these could be accounted for in terms of treatment-induced effects on dry matter production rate. Exceptions to this trend were Cd uptake values measured on a range of treatments, and also all elements determined in grass from the shallow (< 300 m) cover treatments. These latter two anomalies were most exaggerated when precipitation was low. It was concluded that upward movement of metal contaminants in soil solution could best account for these phenomena.