Remediation of lead and cadmium-contaminated soils

Abstract

The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

Effects of the combined pollution of cadmium, lead and zinc on the phytoextraction efficiency of ryegrass (Lolium perenne L.)

“…[25][26][27] According to the literature, ryegrass shows a certain absorption capacity for cadmium, lead and zinc in soil and is a potential heavy metal-enriched plant. 12 The species, 28 growth status, 20,29 enrichment site, 30 physiological and biochemical characteristics 31 and other factors of ryegrass show signicant effects on the distribution of different heavy metals in soil-plant tissues [32][33][34] as well as the absorption, accumulation and enrichment capacity of various heavy metals at different sites. Since ryegrass is a potential heavy metal-enriched plant, it is necessary to improve and regulate its phytoextraction ability under heavy metal combined pollution.…”

Progress of Molecular Display Technology Using Saccharomyces cerevisiae to Achieve Sustainable Development Goals

“…Bioremediation is aimed at the removal or recovery of hazardous substances from biological materials, including living or dead microorganisms and their components, seaweeds, plant materials, and agricultural wastes [ 55 ]. For instance, plants have the ability to neutralize contaminants in soil through absorption and accumulation in their roots [ 56 , 57 ]. Considering the convenience of their preparation as adsorbents, microorganisms have several advantages over plant roots since microbial cells can proliferate faster than plant cells.…”

Benefits of Ryegrass on Multicontaminated Soils Part 1: Effects of Fertilizers on Bioavailability and Accumulation of Metals

“…Among the tolerant plants, ryegrass is currently used as green waste to make compost, to prevent the entrainment of windblown contaminated dust and the soil erosion, and to create public open space/parkland. It was selected for two mains reasons: its importance as a grazing crop and its preconization as a suitable plant for the revegetation of contaminated soils from metallurgical sites [1][2][3]. Among the 10 species of grass in the they are absolutely needed by plants.…”