ARS | Publication request: Use of Biosolids, Composts and by-Products to Remediate Metal Toxic Ecosystems

Submitted to: Agronomy Abstracts
Publication Type: Abstract
Publication Acceptance Date: November 15, 2001
Publication Date: November 11, 2002

Technical Abstract: When mine wastes or smelter-contaminated soils are strongly acidic, phytotoxicity limits plant cover. Often erosion removes much of the contamination, but soils remain barren because of metal phytotoxicity, acidity, infertility, and adverse soil physical properties. Because mixtures of biosolids, manures, and byproducts, or composts made from them can remediate all of these problems, and the soil made calcareous to prevent acidification, we tested use of "Tailor-Made" mixtures at highly contaminated, barren soils at Palmerton, PA, Katowice, Poland, Kellogg, ID, Leadville, CO and other locations. Total limestone equivalent applied was great enough to neutralize soil acidity and provide substantial residual lime equivalent. Organic resources were needed as organic-N fertilizer, P-fertilizer, to improve soil physical properties and make the root environment less hostile. In some locations, the amendments were incorporated in 15-20 cm depth, and in other locations with soils which could not be readily tilled, amendment mixture was surface applied. Locally adapted revegetation species were sown and became established with little difficulty, and plant cover was persistent for 3 or more years of tests conducted. Plant shoot analysis showed that metals were below phytotoxic levels, and P and other nutrients were at adequate levels. Our experience indicates that using mixtures or composts of organic resources and by-products can provide a "one-shot" persistent remediation of soils highly contaminated with Zn, Cd, Pb, or Ni, and plants are safe for consumers. Including high P and Fe in such mixtures improved metal inactivation.