Abstract
Searching for new plants that could phytoextract soil macro-nutrients is one of the main research interests nowadays. In the present study, nine native plant species were collected to determine their potential to uptake six macro-nutrients from the soil of a sewage sludge dump site (SS) in comparison with a reference site (RS). The results showed that the studied native plants can accumulate the macro-nutrients in their tissues regardless of their size or vegetative stages. The concentrations of all macro-nutrients (except K) in the tissues of the most studied plant species were positively correlated with those in the soil. The stoichiometric ratios vary among species and depend on many limiting factors. The values of bioaccumulation and translocation factors were > 1.0, indicating the high tendency of the plants to accumulate the macro-nutrients. Portulaca oleracea growing in the SS accumulated larger quantities of macro-nutrients compared to two perennials growing at the same place. Phragmites australis, Rumex dentatus, Portulaca oleracea, Bassia indica, Amaranthus viridis and Pluchea dioscoridis from the SS; and Portulaca oleracea, Rumex dentatus, Pluchea dioscoridis and Solanum nigrum from the control site showed the highest element accumulation indices, which could be recommended for the phytoextraction of macro-nutrients. We recommend using the studied species in mitigation of the eutrophic status of agricultural soil amended with sewage sludge.