Application of emerging tools and techniques for measuring carbon and microbial communities in reclaimed mine soils

As part of a study of the potential for carbon sequestration in degraded mine lands, we examined the carbon content of reclaimed mine soils treated with soil amendments (e. g., fly ash and biosolids) using two emerging techniques; terminal restriction fragment-length polymorphism (TRFLP) and laser-induced breakdown spectroscopy (LIBS). Both of these techniques have potential use for measuring aspects of carbon content and its role in the soil ecosystem. To better understand the relationship between the microbial community and the amount of carbon within mine soils, we examined the diversity among fungal communities in soils with different carbon content using TRFLP. TRFLP was run on 18S rDNA from polymerase chain reaction (PCR) amplification using primers specific for fungi. Results from the TRFLP were compared to sequencing of 18S clones. The diversity based on sequence analysis was much higher than that indicated by the TRFLP-based analysis. Rarefaction analysis of the data indicated that the total diversity was even higher than we were able to measure with both levels of effort; however, it was clear that we effectively sampled the dominant populations. The LIBS technique displayed a strong linear relationship when compared to conventional techniques (LECO and Walkley-Black) of measuring carbon in soils. In addition, discrepancies were noted between the two conventional techniques for soils with high carbon content.