Print PageThe Southern Appalachian coal region of Eastern Kentucky is a temperate rainforest with a very large terrestrial carbon budget. Reforestation efforts have focused attention to Southern Appalachian forests for their high carbon sequestration potential. If inadequate reclamation processes are used, mined lands could become terrestrial sinks for the CO2 that is released during soil disturbance. In order to better understand reclaimed mined lands’ carbon budgets, compacted and non-compacted soils on reclaimed mines were compared by analyzing plant population/natural succession dynamics and soil development based on carbon and lignin content in plant biomass. Samples were taken from paired reclaimed mine sites of both compacted and non-compacted soils. Using a 25 cm quadrat, aboveground biomass was collected for further carbon and lignin analyses. Belowground biomass was measured from bulk density soil pits 50 cm in depth. The Klason method was used to attain the total acid-insoluble lignin content of biomass samples.
Results/Conclusions
The compacted soil reclaimed mining site had lower levels of carbon stored aboveground in plant material. This indicates that soil development in terms of carbon turnover is slower in the compacted soils than in the non-compacted soils. Litter decomposition is faster on the compacted sites; however, most of the carbon released from the newly broken lignin linkages is lost through photodegradation. Also, a lower diversity of plant species grows on the compacted soils, with primarily only initially seeded plants surviving. The inverse of this is true for the non-compacted soils. Hence, the plant populations present on a reclaimed mine site affect the rate of soil development, with more diversity of aboveground biomass containing more lignin decomposed through biotic degradation allowing for faster soil development into the native sandy loam soils of eastern Kentucky.
Keywords: succession, biomass, lignin, coal mine reclamation, soil development, carbon turnover
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