The six sites studied in the Validation Phase have similar slopes, but different aspects (i.e., face different directions). The research evaluated whether the different aspects affect the levels of sequestration. For example, there may be different amounts of carbon that can be sequestered on south-facing versus north-facing sites.
Soil carbon measurements were compared to undisturbed pastureland nearby to assess how well mine sites sequester carbon. In addition, researchers collected and analyzed soil samples from identified reclaimed mine sites. Sampling mine sites of different ages allowed researchers to calculate the annual rate of change of soil carbon accumulation in mined soils. The sites were geo-referenced and re-sampled over time to assess the change in the soil carbon stock.
Research was also conducted to identify additional reclaimed mine sites in other MRCSP states that are appropriate and available for sampling. Measurements of tree growth, when possible, and soil carbon for reclaimed mineland will also provide additional opportunities to validate carbon accumulation models used for terrestrial sequestration elsewhere. The results from these studies will provide valuable information to both landowners and policymakers.