Soil microbial respiration as a tool to assess post mine reclamation

Abstract

An evaluation of soil quality, which integrates biological, chemical and physical processes, would be beneficial to regulators as well as mining companies when making reclamation decisions. Coal mining regulations require that industry perform soil sampling and submit laboratory results in order to determine pre-mine and reclaimed soil quality. A rapid and accurate biological soil quality method, such as one-day CO2 (1-day CO2) analysis, can be used to determine soil microbial activity which is related to the soils' ability to sustain nutrient cycling. Our objective in this study was to compare native and reclaimed soils from surface-mine operations in order to assess the effectiveness of the 1-day CO2 method as a tool for determining biological soil quality. Soil samples were taken from sites that visually had poor and well-vegetated reclaimed areas of a surface-mine operation as well as an undisturbed native site. Chemical, physical and biological indicators were compared to 1-day CO2 analysis for microbial activity. Results indicate that the biological soil quality indicators as summarized by 1-day CO2 analysis are a more sensitive indicator of soil health on the reclaimed soils tested than chemical analysis alone. One-day CO2 analysis can be a useful additional tool for regulators and mining companies when assessing the soils ability to sustain plant growth and evaluate reclamation success.