Wednesday, November 4, 2009
Convention Center, Exhibit Hall BC, Second Floor
Fabricated soil was created five years ago for the rehabilitation of abandoned mining soil. Soil samples were obtained from different locations named by the presence of certain trees grown on these specific plots. The bacterial colonies were enumerated and identified. Authors acknowledge the assistance US-Microsolutions, Inc. in determining the microbial activity and identification of microorganisms in fabricated soil samples. Microbial composition of FS consisted of fungi imperfecti and various bacterial species. The fungi level during 5 years was diminished but bacterial presence increased and varied over the years of research. Several new forms of microorganisms were found lately- Sphingomonas, Chryzeobacterium and Rhizobium that were not present in earlier years. In the first few years the predominant bacterial species were fermenting and non-fermenting gram-negative bacillus, Bacillus spp., Actinomycete, and Micrococcus spp. Finally, the bacterial content on FS was 100 times higher, than of the mining soil which was a subject of the landscape rehabilitation. By monitoring soil organism dynamics, we can detect detrimental ecosystem changes and prevent further degradation. Soils were also analyzed for metal and nutrient content. The addition of FS added significant organic matter to soil. FS had > 15% OM compared to < 10% for mining soil. Cation exchange capacity varied from 8.5 to 48.0 cmolc/kg. Mining soils contained high levels of some metals, including Zn (> 1300 mg/kg soil), Fe (> 1500 mg/kg soil) and Ni (> 900 mg/kg soil).