There are approximately 400 plant species from 45 plant families that are known to hyperaccumulate metals. Several studies have experimented with Brassica carianata, Brassica juncea and Thalaspi caerulescens as hyperaccumulators and leafy vegetables are known to accumulate heavy metals. At the present time, however, there are no known hyperaccumulators for the most common contaminant in urban soil, lead. Lead is not known to be an essential element for plants, but many studies have shown that various plant species have the ability to absorb lead in the roots and translocate lead to the shoots. We have used spinach (Spinacea oleracea), sunflowers (Helianthus annus), and Indian mustard (Brassica juncea) as phytoaccumulators for lead. We sampled the garden soils before any planting took place, and then again after the plants were harvested, and analyzed them for total and plant-available soil lead using EPA methods. We also analyzed the roots and shoots of harvested plants. We found that in moderately acid soils (pH 5-6.5) with low organic matter, phytoremediation removed at least 100 mg/kg lead after one growing season. (via Urban Soils Potential Contaminants and Remediation Techniques)

There are approximately 400 plant species from 45 plant families that are known to hyperaccumulate metals. Several studies have experimented with Brassica carianata, Brassica juncea and Thalaspi caerulescens as hyperaccumulators and leafy vegetables are known to accumulate heavy metals. At the present time, however, there are no known hyperaccumulators for the most common contaminant in urban soil, lead. Lead is not known to be an essential element for plants, but many studies have shown that various plant species have the ability to absorb lead in the roots and translocate lead to the shoots. We have used spinach (Spinacea oleracea), sunflowers (Helianthus annus), and Indian mustard (Brassica juncea) as phytoaccumulators for lead. We sampled the garden soils before any planting took place, and then again after the plants were harvested, and analyzed them for total and plant-available soil lead using EPA methods. We also analyzed the roots and shoots of harvested plants. We found that in moderately acid soils (pH 5-6.5) with low organic matter, phytoremediation removed at least 100 mg/kg lead after one growing season. (via Urban Soils Potential Contaminants and Remediation Techniques)

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  1. susanmernit posted this