Long-term remediation of compacted urban soils by physical fracturing and incorporation of compost

The study finds that over a 12-year period remediated soils exhibit improved (reduced) bulk density (R2 = 0.50) (P < .0001) (n = 30), increased active carbon (R2 = 0.61) (P < .0001) (n = 30) and increased potentially mineralizable nitrogen (R2 = 0.61) (P < .0001) (n = 30). When S&D soils were compared to unamended (Unam) soils, improvements were found in aggregate stability (S&D = 72.41%, Unam = 34.90%, P < .0001, n = 30), available water holding capacity (S&D = 0.22%, Unam = 0.15%, P < .0001, n = 30), total organic matter (S&D = 8.43%, Unam = 3.23%, P < .0001, n = 30), potentially mineralizable nitrogen (S&D = 27.53 mg/kg, Unam = 3.11 mg/kg, P = 0.0005, n = 30), active carbon (S&D = 1022.47 mg/kg, Unam = 361.60 mg/kg, P < .0001, n = 30), and reduction in bulk density (S&D = 0.89 g/cm3, Unam = 1.47 g/cm3, P < .0001, n = 30). Application of the S&D process provides an alternative to using specified soils and has potential for improving long term soil quality using locally sourced materials and simple methods.