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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Phosphorus adsorption on sandy mine tailings: a comparison of treatments with fertilizers, wood ash, and compost

Orndorff, Zenah W. 14 August 2009 (has links)
Approximately 378 million metric tons of soil in the Upper Coastal Plain of Virginia and North Carolina may be processed during proposed titanium mining.. This area is prime agricultural land, and with proper management productivity can be maintained with treated mine tailings. Since P is usually a limiting plant nutrient, proper P fertilization is essential for continued agricultural productivity. Seven different soil systems including unamended tailings (UT), a series of 5 treatments with fertilizers, wood ash, and increasing rates of compost (treatments 1, 3, 6, 8, and 9), and natural soil (NS) were evaluated and compared with regards to P status. Comparisons were based on standard Langmuir adsorption isotherms, Mehlich III extractable-P, and selected chemical and physical properties including pH, cation exchange capacity, compost rate, and specific surface area. Phosphorus adsorption decreased in the order UT, 1, 3, 6, 8, 9, and NS. Decrease in P adsorption was due primarily to increasing organic matter which both physically blocks P adsorption sites, and competes for these sites. Previous addition of large amounts of P fertilizer caused a decrease in P adsorption by occupying some adsorption sites. Wood ash increased pH, which decreased anion exchange capacity and thereby decreased P adsorption. Treatment 9 (12% compost) most closely resembled the natural soil in terms of P status. Agriculturally, economically, and environmentally, the tailings may be suitably managed with high compost rates, an initial heavy application of P fertilizer, and lighter yearly supplements of P fertilizer. / Master of Science

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