The Influence of Soil Reconstruction Methods on Mineral Sands Mine Soil Properties

Significant deposits of heavy mineral sands (primarily ilmenite and zircon) are located in Virginia in Dinwiddie, Sussex and Greensville counties. Most deposits are located under prime farmland, and thus require intensive reclamation when mined. The objective of this study was to determine the effect of four different mine soil reconstruction methods on soil properties and associated rowcrop productivity. Treatments compared were 1) Biosolids-No Tillage, 2) Biosolids-Conventional Tillage, 3) Lime+NPK fertilized tailings (Control), and 4) 15-cm Topsoil over lime+P treated tailings. Treated plots were cropped to corn (Zea Mays L.) in 2005 and wheat (Triticum aestivum L.) in 2006. Yields were compared to nearby unmined prime farmland yields. Over both growing seasons, the two biosolids treatments produced the highest overall crop yields. The Topsoil treatment produced the lowest corn yields due to relatively poor physical and chemical conditions, but the effect was less obvious for the following wheat crop. Reclaimed land corn and wheat yields were higher than long-term county averages, but they were consistently lower than unmined plots under identical management. Detailed morphological study of 20 mine soil pedons revealed significant root-limiting subsoil compaction and textural stratification. The mine soils classified as Typic Udorthents (11), Typic Udifluvents (4) and Typic Dystrudepts (5). Overall, mined lands can be successfully returned to intensive agricultural production with comparable yields to long-term county averages provided extensive soil amendment and remedial tillage protocols are implemented. However, a significant decrease (~25 to 35%) in initial productivity should be expected relative to unmined prime farmland.

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

2007

Author dc:creator

• Meredith, Kelly Robyn

Chair dc:contributor.committeechair

• Daniels, W. Lee

Committee members dc:contributor.committeemember

• Grisso, Robert D.
• Alley, Marcus M.
• Galbraith, John M.

• Reclamation
• Revegetation
• Bulk Density
• Biosolids

Statement dc:rights

• In Copyright

Licence dc:rights.uri

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

Dc Identifier Other

etd-01202008-125512

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/31006