Sample information for 180 surface soils (top 0-5 cm) collected from across North Carolina (USA) for 15PNIJ-21-GG-02711-SLFO.

In this National Institute of Justice funded grant, two types of surface soils representing scenarios that would potentially benefit the most from new quantitative methods were collected from across the state of North Carolina (USA) in April 2022: a) similar inorganic content but with distinct land use (category type = mineral rich), and b) those with limited inorganic content but recognizable organic fractions (category type = organic rich). At each location (n, 30), samples were collected from paired sites <500 meters apart (A and B). At each paired site, three sub-site samples were collected 1 meter apart to assess method reproducibility, accuracy and small-scale variation that might be realistically observed in questioned-to-known (Q-to-K) comparisons (total n, ~180). Each sample was subjected to examination using methods currently used in practice (e.g., manual color determination, polarized light microscopy, x-ray diffraction), along with three new quantitative methods: 1) instrumental colorimetry, 2) automated scanning electron microscopy energy dispersive X-ray spectroscopy of soil minerals, and 3) DNA metabarcoding of plant, bacteria, arthropods and fungi.