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

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.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Crop and Soil Environmental Sciences

Department dc:contributor.department

Crop and Soil Environmental Sciences

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1995

Author dc:creator

• Orndorff, Zenah W.

• Langmuir isotherm
• titanium

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-08142009-040609

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/44247