Utilização de Lolium perenne L. na fitoestabilização controlada de solos degrad...

• Author(s): Alvarenga, Paula ; Fernandes, Rosa Maria ; Varennes, Amarilis ; Vallini, Giovanni ; Duarte, Elisabeth ; Cunha-Queda, Ana Cristina
• Date: 2011
• Persistent ID: http://hdl.handle.net/10400.5/5006
• Origin: Repositório da UTL
• Subject(s): accumulation factor; assisted phytostabilization; Lolium perenne; mine soils; organic residues
• Document Type: Article
• Language: Portuguese

Description

We studied the application of Lolium per-enne L. and of different organic residues in the assisted phytostabilization of mine-contaminated soils (Aljustrel Mine Area, Iberian Pyrite Belt). Although the applica-tion of the organic residues led to immobilization of Cu, Pb, and Zn in the soil, decreas-ing their effective available fraction, their concentrations in the above-ground plant material did not change. The accumulation factors (AF) obtained were AF(Cu) and AF(Pb) <<1, and AF(Zn) <1, allowing its election as a possible candidate for phytos-tabilization purposes. However, Pb and Cu concentrations in ryegrass shoots were con-sidered toxic, which suggests that there is a risk of contamination of the human food chain. Multivariate statistical analysis em-phasized sewage sludge as the organic resi-due with the greatest capacity to correct soil acidity, and to improve soil characteristics, followed by the compost obtained from municipal solid waste residues. However, an impaired growth was obtained when using the highest application rate (100 Mg ha-1) of both residues. All garden waste compost rates were unable to correct general soil constraints to plant growth.