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This experiment was aimed at verifying the usefulness of phytoremediation using Short Rotation Coppice (SRC) in an urban Zn-contaminated site. Besides elemental uptake and reclamation, the SRC method was applied to evaluate the additional benefits of a green infrastructure. Nine different plants with rapid growth and large biomass production were selected: three Populus clones, three Salix hybrids, and three Robinia genotypes. Annual and biennial coppicing were evaluated. Poplar clones were more productive using annual coppicing, while Salix and Robinia produced higher biomass in blocks not coppiced. Poplar had the highest phytoextraction rate during the second year, with 1077 g/ha. Salix clones S1 and S3 extracted similar quantities using biennial coppicing. After two years, the bioavailable fraction of Zn decreased significantly using all species, from the 26% decrease of Robinia to the 36% decrease of Salix. The short rotation coppice method proved to be useful in an urban context, for both landscape and limiting the access to the contaminated area. Improving the biomass yield through the phytomanagement options (fertilization, irrigation, coppicing, etc.) could make SRC phytoremediation an economic and effective solution to manage urban contaminated areas, coupling the added values of biomass production to the landscape benefits. [ABSTRACT FROM AUTHOR]

Waste from stone and aggregate quarrying industry represents a serious environmental and economic problem in view of the difficulties related to its disposal, especially of the finest fraction. Although some attempts have been made to investigate possible reuse of these materials, little is known about their potential as components of a cultivation substrate. Their low physical and chemical fertility require the mixing with other materials to improve the general properties. The aim of this study was to evaluate if such a prospect product can be employed within the quarry for its environmental rehabilitation. Samples from gangue saw with abrasive shot (GSS), from diamond frame saw (DSS), and mixed sludge (MS)-from gangue and DSS-were collected and mixed with compost, green manure, and soil material. The resulting mixtures were further composted, distributed on parcels within the quarry area and sowed. The original materials and the mixtures were analyzed for metals and hydrocarbons (TPH) and for their phytotoxicity. The parcels were sampled and analyzed after 8 years. The results show that mixing with foreign materials can improve the overall quality and fertility of the sludge and that the mixture is not phytotoxic. Most metals concentrations decreased on mixing and further diminished after 8 years. TPH content was drastically reduced and fertility parameters tend toward equilibrium. This indicates that the residual sludge can be employed for quarrying rehabilitation after improvement of its fertility and of its environmental quality. [ABSTRACT FROM AUTHOR]