Microbe-assisted selenium phytoremediation and phytomanagement of natural seleniferous areas

摘要

Natural seleniferous areas are found worldwide and are generally considered unsafe to use as agricultural land to grow crops because of the high concentration of selenium (Se) in the soil. Selenium is an important environmental contaminant when present at high concentration in food and it could be toxic for animals, humans and plants. Seleniferous areas(containing > 0.5 mg/kg) are particularly prevalent in China, India, Australia, Ireland and the U.S.A.(Dhillon et al., 2003). To avoid Se toxicity and reduce the impact of naturally occurring Se on the biological environment, extensive research has been conducted in the western United States and a vast amount of resources have been allocated to develop management strategies and remediation technologies (Banuelos et al., 2002). Selenium toxicity and deficiency can exist side by side, due to soil Se heterogeneity. Thus, Se removed from seleniferous areas may be beneficial for adjacent low-Se areas.