"study_id","coring_method","roots_flag","sediment_sieved_flag","dry_bulk_density_temperature","dry_bulk_density_time","dry_bulk_density_sample_volume","carbonates_removed","fraction_carbon_type" "sanborn_and_coxson_2020","soil pit","roots and rhizomes included","sediment not sieved","105","24","550","FALSE","total carbon"