Application of the Vetiver System for Phytoremediation of Mercury Pollution in the Lake and Yolo Counties, Northern California

摘要

The Vetiver System was first developed for soil and water conservation in farmlands. While this application still plays a vital role in agricultural lands, recent R&D have demonstrated that vetiver grass is also highly suitable for phytoremedial application due to some of its extraordinary features. These include a massive and deep root system, tolerance to extreme climatic variations such as prolonged drought, flood, submergence, fire, frost and heat waves. It is also tolerant to a wide range of soil acidity, alkalinity, salinity, sodicity, and elevated levels of Aluminium, Manganese, and heavy metals such as Arsenic, Cadmium, Chromium, Nickel, Lead, Zinc, Mercury, Selenium and Copper in the soil. Successful rehabilitation of mine tailings and landfills with elevated levels of heavy metals in Australia, China and South Africa indicates that the Vetiver System should provide a powerful phytoremedial tool for the attenuation of the mercury pollution problem in Yolo and Lake Counties by trapping and containing both the air and water born insoluble mercury at sources,and by reducing the soluble fraction in acid mine drainage.