Phytoextractive potential of Miscanthus giganteus and Sida hermaphrodita growing under moderate pollution of soil with Zn and Pb

Abstract

The most cost-effective and pro-ecological method of purifying the environment moderately contaminated with heavy metals is the extraction of such substances from the soil by plants, which are able to grow under conditions of high concentrations of toxic metals and to accumulate them in their tissue. The 3-year microplot experiment with perennial energy crops, miscanthus (Miscanthus giganteus) and Virginia mallow (Sida hermaphrodita), was conducted in the Experimental Station of the Institute of Soil Science and Plant Cultivation in Pulawy, Poland (51°25’N, 21°58‘E). The experiment was carried out on two different soils with varying levels of acidity, moderately contaminated with zinc and lead. The results from the three first years of cultivation of these plants (2008-2010) indicate that miscanthus and Virginia mallow can be cultivated on soils, moderately contaminated with zinc and lead. Miscanthus turned out to be a more tolerant species. Its dry matter yield on average was two times higher and accumulated higher quantities of zinc and lead in biomass compared to Virginia mallow. Thus, the phytoextraction of Zn and Pb from the soil contaminated with metals was much greater for the miscanthus than for mallow, and significantly higher uptake of Zn than Pb was observed.