Removal of Zinc Pollution by Using Some Hyperaccumulator Plants in Sewage Sludge Treated and Untreated Soils

Abstract

Soil pollution caused by heavy metals has emerged as one of the most significant environmental problems in the world. In soils, specific plant species are able to grow, adapt and absorb heavy metals. Phytoremediation is an emerging technology in which higher plants are used to reclaim the contaminated environment. In this study, the possibilities of removing the pollution caused by Zn, which is applied to the loamy soil together with and without sewage sludge at increasing levels (0, 75, 150, 300, 600 and 1200 mu g g-1), has been researched with certain hyperaccumulator plants such as Brassica juncea, Raphanus sativus and Silene vulgaris grown in Bafra ecological conditions. In order to clean Zn added to the soil at increasing levels with or without sewage sludge by using phytoremediation technology, Silene vulgaris was found to remove the highest amount of Zn in the soil by producing the greatest amount of biomass in the ecological conditions of the region compared to Brassica juncea and Raphanus sativus, and other hyperaccumulator plants grown in the plots. Significant differences were determined in the development of plants and Zn removal between the sludge treated and untreated plots. Water-soluble Zn, which was found at high levels in the cultivation of plants at 600 and 1200 mu g g-1 Zn application doses in the sewage sludge treated plots, was determined at lower levels at the end of the harvest of the plants. In the application of increasing levels of Zn with sewage sludge, the lowest organic bound Zn was determined in the plots where Silene vulgaris was grown. The highest exchangeable Zn concentration was determined in soil samples taken after the harvest of the Raphanus sativus plant among the hyperaccumulator plants grown at all Zn application doses in the trials with and without sewage sludge application.