The GERI (Genomics Enhanced Reclamation Index) Stockpile Project

When direct replacement of salvaged soil on a reclamation site is not possible, soil may be stockpiled for years or decades before replacement. This project looked at the impact of stockpiling on soil health, asking: (1) does stockpiled topsoil contribute to healthy, functioning ecosystems over time and will stored soils require enhancement before placement for reclamation (if so, what enhancements will be needed)? and (2) in reclaimed ecosystems, can below ground ecosystem parameters be linked to aboveground ecosystem parameters for an integrative assessment of ecosystem health, and can this provide a more rapid assessment of ecosystem health (and reclamation trajectory) than current methodologies? To address these questions, this project assessed soil physical, chemical, and biological parameters, as well as above-ground plant parameters, in operational stockpiles. Cutting-edge genomic tools linked above ground and below ground parameters to obtain a better assessment of soil health.

If direct placement is not possible, it is best to use soils stockpiled for several years, but less than a decade, for reclamation. Stockpiles should be as shallow and broad as possible, and surface soils (upper 20 cm) are best for reclamation. If deeper soils must be used, we recommend mixing them with surface soil (the mixing ratio needs further study), perhaps by mixing at the stockpile site, before reclamation. If surface soils are used, care must be taken, as undesirable weedy species are likely to dominate a site initially; mixing with deeper soils may mitigate some of these issues. Stockpiled soils may lead to more rapid growth of plant species initially due to higher concentrations of bioavailable nutrients.